The World of Ham Radio CD-ROM From amsoft@epix.net Wed Jun 05 20:33:14 1996 From: anthonys@ix.netcom.com(Anthony Severdia) Newsgroups: rec.radio.amateur.antenna Subject: Re: 1/2 wave dipole vs. full wave question. Date: 31 May 1996 23:53:12 GMT Message-ID: <4oo0p8$m7t@dfw-ixnews2.ix.netcom.com> References: <4okppt$ms2@shore.shore.net> <4ons6d$fnb@newsbf02.news.aol.com> In <4ons6d$fnb@newsbf02.news.aol.com> parf@aol.com (Parf) writes: > >Assuming you are still intending on center feeding the antenna: >The feed impedance would be VERY high (somewhat dependent upon conductor diameter). Yes, the impedance will be very high but it is easily transformed to low with a 1/4 wave ladder line. Is so? > >From memory, I believe the pattern is cloverleaf- both halves are in >phase. "Stoking" my memory, this is correct for an antenna 1/2 wave above earth. For 1 wave antenna the cloverleaf is quite broad and at lesser heights becomes even yet broader. Perhaps someone with a "magic" program can confirm this. > >Look in the Handbook @ extended double Zepps- a little more gain and feed techniques. Good advice, Dale! Anyone seriously exploring must pound the books for the best available information. -=Tony=- W6ANV San Francisco From amsoft@epix.net Wed Jun 05 20:33:15 1996 From: bbruhns@newshost.li.net (Bob Bruhns) Newsgroups: rec.radio.amateur.antenna Subject: 1/2 wave dipole vs. full wave question. Date: 2 Jun 1996 03:33:39 GMT Message-ID: <4or22k$auq@linet06.li.net> The impedance of a center-fed 1/2 wave dipole varies around 72 ohms, depending on its height. The impedance of a center-fed full-wave dipole varies around about 800 ohms depending on height. A full-wave dipole is two 1/2 wave dipoles in phase. Its main lobe of radiation is perpendicular to the wire, and somewhat narrower than that of a 1/2 wave dipole. This gives it a bit of gain compared to a 1/2 wave dipole. "Open-wire" feedline matches this kind of antenna quite well. A simple tuner can match the antenna and feedline to 50 ohm coax over a very wide frequency range. This "two half-waves in phase" design has been very popular over the years. Bob Bruhns, WA3WDR, bbruhns@li.net From amsoft@epix.net Wed Jun 05 20:33:16 1996 From: Steve Richards Newsgroups: rec.radio.amateur.antenna Subject: Re: 2.4 GHz antennas Date: Sat, 01 Jun 1996 22:45:46 +1030 Message-ID: <31B03472.908@ozemail.com.au> References: <31A59CCB.24A5@ozemail.com.au> <4olr3d$chd$2@mhadf.production.compuserve.com> Roger Cox wrote: > > There is a BIG difference between a $A700 WLAN antenna and a > US$10000 MMDS "Broadcast" antenna. WLAN is limited here in the > states to 1 watt. The antenna can have no more than 6 dB gain, > otherwise the transmitter output power must be reduced by the > same amount that the antenna gain is over the 6 dB figure. Most > of the WLAN companies transmit less than 100 mW anyway. Typical > range is less than 3 miles, even when using directive antennas. > Some people have gotten around the FCC limitations by using the 6 > dB gain antenna only on transmit, and using 20 to 30 dB gain > dishes on receive. > > The MMDS antenna is meant for HIGH-POWER broadcasting, and it > costs more because of that. > > 73, Roger WB0DGF > > -- > Roger CoxI'm not sure about what you are saying Roger. I know that you are s tating the obvious , so what are you trying to say? Steve From amsoft@epix.net Wed Jun 05 20:33:17 1996 From: mluther@tamu.edu Newsgroups: rec.radio.amateur.antenna Subject: Re: 40 Meter Quad - Any Manufacturers? Date: 1 Jun 1996 21:27:51 GMT Message-ID: <4oqckn$e8a@news.tamu.edu> References: <4om0kh$e1a@linda.teleport.com> Reply-To: mluther@tamu.edu In <4om0kh$e1a@linda.teleport.com>, larryj@teleport.com (Larry R. Johnson) wri tes: >Does any Quad company manufacture a 40 MEter Quad? Lightning Bolt used to >make them, but the demand just wasn't there to keep them in production. >Anyone know if any other companies make them? >Thanks, >Larry Johnson > >larryj@teleport.com > >-- >Larry Johnson - Portland, OR - (503)246-5645 home, (503) 823-4577 work >Ham Radio: K7LJ - 145.39 K7LJ/RPT, 443.400 , 29.6 FM You rattled off the only one I recall... except, perhaps, Larry R. Johnson & Company... :) Humor intended! Mike W5WQN as a guest at leviathan.tamu.exu (No mail address there) From amsoft@epix.net Wed Jun 05 20:33:18 1996 From: cmm@hookup.net Newsgroups: rec.radio.amateur.antenna Subject: 440 Antenna Plans? Date: Sun, 02 Jun 1996 15:36:45 GMT Message-ID: <4oscdm$q5k@nic.wat.hookup.net> Does anyone have plans with demensions for a 442 Mhz antenna. I would like to build one for emergency use with a PVC boom that will split in the middle for easy transport. Boom lenght 5-6 feet. 73 John VE3DOS From amsoft@epix.net Wed Jun 05 20:33:19 1996 From: Erik Skovgaard Newsgroups: rec.radio.amateur.antenna Subject: AEA 6m Halo Antenna Date: 1 Jun 1996 04:46:59 GMT Message-ID: <4ooi03$la9@googol.bctel.net> I noticed that AEA is advertising a 6m halo antenna in the June QST. Has anyone managed to get information on it? - price? 73 de VE7MDL ....Erik. From amsoft@epix.net Wed Jun 05 20:33:23 1996 From: w7el@teleport.com (Roy Lewallen) Newsgroups: rec.radio.amateur.antenna Subject: Re: Antennas (Part II) Date: Wed, 05 Jun 96 18:28:04 GMT Message-ID: <4p4ji1$l0n@nadine.teleport.com> References: <4ovf2u$5hs@usenet.srv.cis.pitt.edu> <31B4E7CF.1716@southwind.net> <4p3vbd$ovh@usenet.srv.cis.pitt.edu> In article <4p3vbd$ovh@usenet.srv.cis.pitt.edu>, kamst39+@pitt.edu (Keith A Monahan) wrote: >Ken Bessler (KG0WX) (kg0wx@southwind.net) wrote: > >: Hey Keith, why don't you get a license and learn for yourself? Remember the >: old saying: Give a man a fish......... > > >: 73's and good luck on your test (if you take one)! >: -- > >: Ken Bessler KG0WX >: Design Services Company >: http://www2.southwind.net/~kg0wx >: Model railroad designing > >Ken, > > How about simply answering my questions? There is nothing wrong with >people who have more experience sharing knowledge with people of less >experience. Even if the answers to my questions were found in test material, >I would *still* ask for people's opinions. > >Keith Alas, Ken was being too subtle. Keith, it seems from your post that you have no license to transmit on the frequencies you quoted. Hams in general are reluctant to help anyone transmit illegally. We have enough trouble as it is with unlicensed operators without helping them out. Consequently, I don't think you'll get much help in this newsgroup, but it doesn't have anything to do with your lack of experience -- just your lack of a license to legally transmit. Roy Lewallen, W7EL From amsoft@epix.net Wed Jun 05 20:33:25 1996 From: Merv Stump Newsgroups: rec.radio.amateur.antenna Subject: Bobtail Curtain - Gain Versus Feedpoint Date: 4 Jun 1996 21:42:42 GMT Message-ID: <4p2aki$q25@mtinsc01-mgt.ops.worldnet.att.net> I can't easily find the original postings on the subject, but there were 3 or 4 items on Bobtails and feeding them at voltage nodes versus current nodes. I modeled the antenna optimizing for gain and resonance at 7.175 when fed at a current node (top of the center section). First interesting result is that the antenna appears to be electrically short - for a frequency of 7.175 the vertical sections needed to be 36.6 feet to approach resonance. The horizontal sections came out to be 66.7 feet. The model was done over "average" ground. Results were as follows: Fed at the CURRENT NODE: GAIN 2.88dBd Impedance 47 +j.3 SWR 1.07 Maximum Radiation Elevation Angle 22 degrees 3 db points 49 degrees. Fed at the VOLTAGE NODE GAIN 2.94 dBd Impedance 5380 -j1074 SWR 109 Maximum Radiation Elevation Angle 22 degrees 3 db points 50 degrees. I then repeated the model with the addition of 100 radials, made of #12 wire, 70 feet long. Fed at the CURRENT NODE: Gain 4.25dBd Impedance - No Change SWR - No Change Maximum Radiation Elevation Angle 24 degrees 3db points - No Change Fed at the VOLTAGE NODE: Gain 4.31dBd Impedance 5272 -j1042 SWR 111 Maximum Radiation Elevation Angle 24 degrees 3 db points 49 degrees. If this model is infact valid two things appear obvious: 1. In any event you need a good ground system to make it perform. 2. Going to all the trouble to match at the voltage node seems hardly worth the trouble for 06 db. Question is: Does anybody really believe this? Comments? Questions? Corrections? Regards, Merv From amsoft@epix.net Wed Jun 05 20:33:26 1996 From: jafl@msg.ti.com (Jim Flanders) Newsgroups: rec.radio.amateur.antenna Subject: Re: DDRR antenna Date: 3 Jun 1996 18:50:28 GMT Message-ID: <4ovc5k$j1r@ganesh.mc.ti.com> References: <4nfi1d$imv@mksrv1.dseg.ti.com> <31A0FD48.7BB9@erols.com> <31A7FB91.32D7@odyssee.net> <4of131$5eg@fcnews.fc.hp.com> In article <4of131$5eg@fcnews.fc.hp.com>, eal says... > >Madjid wrote: >>The DDRR antenna as presented in the ARRL Handbook is just an >>approximation of the real thing. >> >>The DDRR was designed by Dr. Boyer for Northrop in the 60's and >>first described in Electronics Jan 11 1963 "Hula-Hoops antennas". >>Comments that it is based on "idiotic" theory are completely Wrong! >> >Since I was the person who posted the "idiotic" comment, I will expand on SNIP . . . Well said Ed. The notebook Idea included. Occaisionally (not too often) when I read these comments I think of the Blind Men and the Elephant parable, except here - too few commentors have ever touched a DDRR. Jim W0OOG/5 147.180 & 14.243 (subvets net 11:30 CST) From amsoft@epix.net Wed Jun 05 20:33:26 1996 From: jackl@pinetree.microserve.com (WB3U) Newsgroups: rec.radio.amateur.antenna Subject: Re: DEMAW'S 160m Shortened Vertical Date: Mon, 03 Jun 96 13:33:55 GMT Message-ID: <4outt7$fhv@crash.microserve.net> References: <4otrq2$k5i@marine.jumppoint.com> jsm@deepcove.com (Steve McDonald) wrote: >Just wondering if anybody has seen the latest CQ article (by >Doug Demaw) describing short top-loaded vertical wire antennas for >top band and 75m? They look extremely interesting. >Has anyone had experience on 160 with a similar type of antenna? Jerry Sevick has been building these and publishing articles on their construction for years. If you're interested in this approach, his work is highly recommended. 73, Jack WB3U From amsoft@epix.net Wed Jun 05 20:33:27 1996 From: jackl@pinetree.microserve.com (WB3U) Newsgroups: rec.radio.amateur.antenna Subject: Re: Distance between antenna and Rig ? Date: Sat, 01 Jun 96 16:39:05 GMT Message-ID: <4opvvr$n8g@crash.microserve.net> References: <31B065D9.1428@nextel.net> "jaiyoung,yi" wrote: >Is it real true that distance between antenna and rig should >accurately be made to meet the requirements of electrical length >of that antenna? In the case of coaxial feed to a balanced antenna, feedline length will have no significant impact (other than its normal loss) as long as A) the antenna is resonant, B) the impedance of the antenna matches the feedline, and C) a balun is used at feedpoint of the antenna. >In my case, on the top of building,where antenna is installed, >the VSWR from 2 element quad for 14.230, which I may believe >that might be resonant point, shows 1.1:1, however it indicate >same VSWR with frequency goes up automatically. Sorry, but could you rephrase this? I don't understand what you mean. >I have heavy TVI, Tel.I complaing from neighbours. This could be the result of direct radiation from the antenna or unwanted radiation from the feedline. The lattrer might be resolved by using a choke balun at the antenna (assuming you're using coaxial feed). Can you provide a more detailed description of the components in the feed system? 73, Jack WB3U From amsoft@epix.net Wed Jun 05 20:33:28 1996 From: "jaiyoung,yi" Newsgroups: rec.radio.amateur.antenna Subject: Distance between antenna and Rig ? Date: Sat, 01 Jun 1996 08:46:33 -0700 Message-ID: <31B065D9.1428@nextel.net> Is it real true that distance between antenna and rig should accurately be made to meet the requirements of electrical length of that antenna? In my case, on the top of building,where antenna is installed, the VSWR from 2 element quad for 14.230, which I may believe that might be resonant point, shows 1.1:1, however it indicate same VSWR with frequency goes up automatically. I have heavy TVI, Tel.I complaing from neighbours. some body say that I should pay my attention to the legnth of cable feeder. Is it true ? any body give me some solution will highly be appreciated. From amsoft@epix.net Wed Jun 05 20:33:29 1996 From: Steve Dobak Newsgroups: rec.radio.amateur.antenna Subject: Re: FM band preselector question Date: Sun, 02 Jun 1996 11:05:27 -0400 Message-ID: <31B1ADB7.5FC@prolog.net> References: <4obiuq$5ks@castor.utu.fi> To: "[yr{s, Pertti Olavi" [yr{s, Pertti Olavi wrote: > > Hello > > > Is it possible to construct a FM band 87.5-108 MHz preselector equal > to that often used on medium and short waves to add extra selectivity > (and sensitivity). > > I have big problems associated with a nearby transmitter tower with 6 > pieces of 60 kw transmitters, only 3 kms away from my QTH. These cause > severe difficulties with intermodulation signals and it is very difficult > to practice any dx-listening on the FM band. I thought it would be > possible to reduce or eliminate my problems by using a preselctor with > tuned circuits ahead my receiver, and possibly some traps for the > local transmitters. But I do not know how to make them and if it is > possible or not. Any help appreciated!! > > 73 > > Pertti Lots of luck, you need either commercial grade filtering which does not come c heap, a move or maybe a good voo-doo dance, While employed at a 50 kw fm station I would ge t nasty-grams quite often from people within a few miles of the station and trying to listen to a station a 100 miles away with his antenna pointing right at the tower, and didnt understand why he hear d us all over the band. Checking out the sites where we caused interferance truly made me wonder about the average IQ of the human race, The fixes or the closest I could come uasually involved red oing the entire setup, throwing all the radio-shack preamps in the garbage, I one case I found 6 in l ine, and put good cable and tuneable filters in line, but the preamps if any were good pro gear, the traps likewise (Blonder-Tounge) put new feedline up and make sure everything had a good solid connection, with out going into to much detail dont extect to have perfection with a $50 K-Mart stereo, and dont even bother with any addons from radio shack, perple couldnt quite hear what they wanted so the salesman at the local radio-shack would be glad to sell then all the garbage they wanted to buy, I got all the problems r esolved but still have nightmares I shudder to think some of these people are on the road when I also am, I hope they drive better than they put up antennas Later Steve-wb3amg From amsoft@epix.net Wed Jun 05 20:33:30 1996 From: Andy Barrow Newsgroups: rec.radio.amateur.antenna Subject: G5RV Dimensions Date: Sat, 01 Jun 1996 13:36:53 -0700 Message-ID: <31B0A9E5.4CBB@ccnet.com> Anyone know the dimensions of a 40meter G5RV? I'm thinking it's just a 1/2 wave dipole with a 1/4 wave section of balanced feeder, but I don't want to go to all the trouble and find out that's wrong. 73, Andy Barrow WD6CWR abarrow@ccnet.com From amsoft@epix.net Wed Jun 05 20:33:31 1996 From: blanton@ni.net (J. L. Blanton) Newsgroups: rec.radio.amateur.antenna Subject: Re: Help homebrewing a mobile GPS antenna (quadrifilar?) Date: Sat, 01 Jun 1996 12:30:53 -0800 Message-ID: References: Steve Peters wrote: > >I am looking to build a homebrew antenna that will function in the band > >used to receive GPS signals. You might try an etched cavity-backed spiral antenna. It's circularly polarized, low-profile and cheap (but also low-gain). Lee WA8YBT From amsoft@epix.net Wed Jun 05 20:33:32 1996 From: "Ian White, G3SEK" Newsgroups: rec.radio.amateur.antenna Subject: Re: Help With 2 meter T-match Date: Sun, 2 Jun 1996 22:09:08 +0100 Distribution: world Message-ID: References: <31B1BEF1.69A8@gteais.com> Al, NW2M wrote: >I need some help. I have build a long 2 meter yagi (34 feet) with a >balanced T-match. I do not know the formulas for caculating the >matching dimensions. The driven element is 3/16 (.177) brass tube and >the T match is .2 diameter brass rod. Spacing is 1.25 inches. > >After looking at the K1FO design, I made the matching section the same >length. My diameters are different. So, My match exceeds 3:1 when the >two shorting stubs are out near the ends of the T-match where they >belong. As I slide the shorting stubs inward, the match finally appears >1:1, but only 3 inches on either side of the boom. > >Does anyone have the caculation for a T-match using a 3/16" driven >element? There are possibly some misconceptions here about where the shorting stubs "belong", and what is the right place for them. The feedpoint impedance of the yagi (the impedance you would measure if you opened up the centre of the driven element) will have a resistive component somewhere in the 15-50 ohm region, depending on the dimensions and spacings of the parasitic elements as well as the dimensions of the driven element. The feedpoint impedance will also have a reactive component which depends mostly on the length of the driven element itself. Unless your antenna design is very similar to the K1FO, your feedpoint impedance may be wildly different from his, and Steve's T-match dimensions will be no guide at all. A T-match is actually two gamma matches back-to-back, and the whole thing is symmetrical about the midline. Thus you are designing to transform one-half of the feedpoint impedance to 100 ohms. If you know the feedpoint impedance from a computer simulation, you can calculate the gamma-match values using the GAMMA program on the ARRL Antenna Book disk. If you don't know the feedpoint impedance, it's back to cut-and- try, although some theoretical understanding can be very useful if it doesn't work first time. For a gamma match, the variables are the diameter ratio of the driven element and the gamma arm, the spacing of the gamma arm (as a ratio of either diameter), the position of the shorting bar, and the series capacitance. Each configuration of diameter and spacing ratios has a limited range of impedance matching; some impedances cannot be matched with any combination of shorting bar position or series capacitance - you have to relocate the gamma arm and/or change its diameter. One difference between the classical gamma and T-matches and the usual VHF/UHF implementation is that there are no series capacitors in the matching arms. The trick is to adjust the driven element length (feedpoint reactance) so that no capacitor is needed. The "correct" location for the shorting bars is wherever it matches. If you require the shorting bars to be right out at the far ends, the T- match has turned into an "unequal folded dipole". In that case your only variable parameters are the diameter and spacing ratios, and the overall length of the driven element. Such a configuration cannot really be adjusted, except by rebuilding it each time. If you really want the shorting bars to be farther out than they are at present, you'll probably need to make the T arms thicker and/or closer to the driven element. > >The antenna works great! If the SWR is OK and you're happy with the gain and pattern of the antenna, what else needs fixing? Move on to the next step - more power! Hope this helps. 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) Professionally: IFW Technical Services Clear technical English - anywhere. From amsoft@epix.net Wed Jun 05 20:33:34 1996 From: grant burris@unknown.address.com (Grant Burris) Newsgroups: rec.radio.amateur.antenna Subject: Re: Larsen glass mount antennas Date: 3 Jun 1996 01:07:39 GMT Message-ID: <4otdsr$rii@dfw-ixnews3.ix.netcom.com> References: <319d1a33.3929389@news.dxnet.com> <4nqe7c$qge@hpcvsnz.cv.hp.com> <4nqts7$4cqi@news-s01.ny.us.ibm.net> <31A347FC.4630@tor.comm.mot.com> <4of1gk$er@ornews.intel.com> In article <4of1gk$er@ornews.intel.com>, Collier_Chun@ccm.hf.intel.com (Collie r Chun) wrote: > In article <31A347FC.4630@tor.comm.mot.com>, louisb@tor.comm.mot.com says... > >I was concerned about the effectiveness of glass mount antennas through > >the shading pattern > >on my 92 Chev Corsica, so I bought a cheapo Midland glass-mount dual > >band and did an > >experiement (naw, that's too easy! It's better to talk it to death...) > > > >I applied the antenna to the side window, then to the back window, both > >times using masking > >tape to hold everything in place. I then measured the transmit SWR with > >a good Bird meter. I couldn't measure receive signal strength because > >I'm using a recycled commercial mobile. > > > >To my surprise, the SWR was slightly better on the back windshield > >(1.4:1 vs. 1.5:1 typically). > >My conclusions: > >1) the shading has no effect; > >2) the height of the antenna above the car roof is important (that would > >explain the > > performance of the antenna on the side window of your friend's van). > >3) alignment of the inside and outside portions is very important. > > > > Something to note: many of the glass-mount antennas have matching > networks located on the inside of the glass, then do a high-impedance > capacitive coupling to the passive antenna element through the glass. > According to the Larsen engineer who spoke at one of our club meetings > some time back, this has several interesting effects, namely, since the > matching network is on the inside of the glass, you can almost match > with NO antenna outside. Low SWR indicates that little power is being > reflected back to the transmitter, and does not necessarily indicate an > efficient antenna (e.g.: dummy load). Another effect is that the antenna > system is more vulnerable to conductive objects near it, like wipers, > defogging grids, etc. > > The Larsen coupling system uses a low impedance coupling through > the glass; hence the two capacitive plates you see on the mounting > area. The matching network is actually located in the outside box, > hence the large size of the outside mounting box. This reduces or > eliminates the effects mentioned before. > > 73's, > Collier Chun > NM7B > I have a condition (phenomenom) related to installation of a Larsen glass moun t antenna. I'm wondering if the SWR has any bearing on this phenomenon or what h as set this condition in motion. I installed a 220 mhz band Larsen antenna on a vehicle rear window that does n ot have a rear defroster grid. SWR measures about 2.5:1. When transmitting, the radio also transmits ANY and ALL static sounds that are generated by touching one piece of metal to another in the general vicinity of the transmitter. The sensitivity (?) is beyond anything I've seen. Example: Movement of the thrott le linkage (while sitting stationary with engine dead) will make a conversation almost unreadable. Rubbing a small knife blade along the teeth of a file will produce a sound like canvas ripping and makes all conversation unreadable. Yo u get the idea. ANY metal moving against ANY metal anywher near the vehicle wil l result in this condition. Conditon did not exist prior to installation of gla ss mount antenna. Radio operates fine in other vehicles, in home with power suppl y, and in the subject vehicle when a magmount Larsen antenna is stuck on the roof . I originally began with the KG220 antenna kit. I used a BNC connector first. I replaced it with another BNC connector. Finally I installed the PL259 connecto r that can in the kit. No change from one connector to the other. I've always been pretty handy at assembling connectors and these are no exception. I've tested for shorts and opens, etc. In the receive mode, everything is close to normal except for a faint alternator whine that I never had before. If anyone has any suggestions I'd appreciate hearing them. Radio is a Kenwood TM2530A. Grant ...agburris@ix.netcom.com N6XRR From amsoft@epix.net Wed Jun 05 20:33:34 1996 From: Raimo Makela Newsgroups: rec.radio.amateur.antenna Subject: List of radiostations 2.3 to 5.7 MHz Date: Sun, 02 Jun 1996 16:42:10 +0300 Message-ID: <31B19A32.3E27@pp.kolumbus.fi> New Bookmark! See our list. Over 600 shortwave radiostations from 2.3 to 5.7 MHz. http://www.yle.fi/sataradio/tropical.html /RM From amsoft@epix.net Wed Jun 05 20:33:37 1996 From: Steve Dobak Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.misc Subject: Re: MFJ-259/AEA-ISOLOOP/MFJ-1621 Date: Sun, 02 Jun 1996 10:52:05 -0400 Message-ID: <31B1AA95.2695@prolog.net> References: <4ob94m$j2k@news.linknet.net> To: Jonathan Helis Jonathan Helis wrote: > > I have an MFJ-259 antenna analyzer that I use to tune up my AEA-Isoloop > and MFJ-1621 54 inch whip antenna for HF. > > The problem is that I don't get an accurate reading on the 1621. > Example: Yesterday, I adjusted the 1621 to an SWR of 1.2:1 on 40 > meters(something I have done many times before at another QTH), but when > I hooked up the rig to it, the rig shut down from too high an SWR! On > the other hand, when I tuned up the Isoloop to an SWR of 1.7:1 on 10 > meters, 20 meters, and an SWR of 1:1 on 17 meters using the analyzer, > when I hooked up the rig, the SWR matched and I was able to work some > stations. > > The rig is a Kenwood TS-140S, I have a Daiwa SWR meter, an MFJ low pass > filter and antenna switch. When I connect the analyzer, I connect it to > the SWR meter, the same way I connect the rig so it sees what the rig > sees. I don't have problems with inaccurate readings on the Isoloop, > just the 1621. > > Anyone know what is causing this? > > 73, > > Jon Helis, KB5IAV Are you sure that the bridge was calibrated, You can check the bridge with a k nown resistive source before each use, also the readout for the reactive componet can be frequency d ependant. Also make sure the analyzer is seeing the same value as your rig as, unless you have a 1 to 1 swr the value you measure will change as you measure the impedance at other places in the line steve wb3amg From amsoft@epix.net Wed Jun 05 20:33:38 1996 From: caveman@castles.com (Mike Morrow) Newsgroups: rec.radio.amateur.antenna Subject: MFJ1798 Capacitance Hat Vertical -- Opinions, please Date: Sat, 01 Jun 96 19:44:05 GMT Message-ID: <4oq6d6$7g6@chewy.castles.com> This is a repost with an expanded subject line. I am looking for experiences with the antenna in the subject. This is the one with the capacitance hat on the top and the bottom. I wonder how they work, do they need additional grounding, do the 'like' additional grounding. Someone must have some experience with one of these. Thanks for any info, Mike/AV6NN _/_/ _/_/ _/ _/ _/ _/_/_/_/ _/ _/ _/ _/ _/ _/ _/ _/ Mike/AB6NN _/ _/_/ _/ _/ _/_/ _/_/_/ Caveman@Castles.com _/ _/ _/ _/ _/ _/ _/ Fully MIME capable _/ _/ _/ _/ _/ _/_/_/_/_/ From amsoft@epix.net Wed Jun 05 20:33:39 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Multi-banding a bug catcher? Date: 2 Jun 1996 19:27:25 -0400 Message-ID: <4ot80t$918@newsbf02.news.aol.com> References: <4oj5br$1gse@chnews.ch.intel.com> In article <4oj5br$1gse@chnews.ch.intel.com>, cmoore@vegas.ch.intel.com (Cecil A. Moore~) writes: >So for mobile operation on 75m and 40m and >20m-10m, only two relays are needed. The bugcatcher >coil is modified so that it resonates on 3.8 MHz with >no shunts. One relay shorts out part of the coil to >resonate at 7.25 MHz. The second relay shorts out >the entire coil for 10m-20m operation. How does that >sound? > >73, Cecil, KG7BK, OOTC (not speaking for my employer) > > Sound good if the relays will take the voltage on 3.8 MHz. Why not just put a large hat on top of a thin mast and feed the thing with a SGC-like tuner on all bands? The upper frequency limit (for low angle radiation) is where the mast is over 5/16 wl long. 73 Tom From amsoft@epix.net Wed Jun 05 20:33:40 1996 From: Brian Olliver Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.homebrew Subject: Re: need help with wire dipole Date: Wed, 5 Jun 1996 00:07:30 +0100 Distribution: world Message-ID: References: In article <4okuue$9st@mtinsc01-mgt.ops.worldnet.att.net>, Chuck Bland writes >jackl@pinetree.microserve.com (WB3U) wrote: >> charlie@netdepot.com (Charlie Fortner) wrote: >> >>>I'm planning to put up a 250 ft (approx. full wave 80m) wire >>>dipole and feed it with ladder line for use as a multiband antenna. >> >>What method are you planning to use to drive the ladder line? A >>balun will probably be less than satisfactory due to the high >>impedances involved on some bands. >> >>73, >>Jack WB3U > >A link-coupled tuner would do the job quite nicely. Sure, it may set >technology back about 30 years, but the system would be better than a >"mere balun". > >Chuck - n6dbt > > -i don't think a full wave dipole will radiate "check it out" maximum voltage will be at the centre of the half conductors thus cancelling each other- Brian Olliver From amsoft@epix.net Wed Jun 05 20:33:41 1996 From: Brian Webb <102670.1206@CompuServe.COM> Newsgroups: rec.radio.amateur.antenna Subject: Re: Radio Shack Tandy Coax any good? Date: 31 May 1996 23:00:14 GMT Message-ID: <4ontlu$n08$1@mhadf.production.compuserve.com> References: <4oaubn$q0g@newsbf02.news.aol.com> If you're operating at VHF or UHF, the quality of the connectors and cable makes a big difference. At HF it probably still matters, but less so. Why spend big bucks on ham radio gear and the skimp on the connectors and coax? Radio Shack connectors and cable have both been condemned by hams who have compared RS's products with their counterparts from other manufacturers using test equipment. I'd use Belden 9913 or fat RG-8 and commcerical-grade amphenol connectors (first choice for me are silver/teflon mil-spec con- nectors). 73s Brian KD6NRP (Admitted perfectionist) From amsoft@epix.net Wed Jun 05 20:33:42 1996 From: vcoletti@mclink.it (Vinicio Coletti) Newsgroups: rec.radio.amateur.antenna Subject: Re: Small HF Quad ideas Date: Sat, 01 Jun 1996 01:38:31 GMT Message-ID: <4oooet$1ak@dg2.iunet.it> References: <4o18dg$4v2@infa.central.susx.ac.uk> Monty Wilson wrote: >Soundsa likea Father Guido Sarducci hasa gottena interesteda >inna radio, eh? >Youre'a fiva by nyna my child. >-- >.........Monty. >mwilson@flex.net I think this is NOT so polite. Vinicio Coletti vcoletti@mclink.it http://www.webcom.com/vcoletti From amsoft@epix.net Wed Jun 05 20:33:42 1996 From: Edward Oros Newsgroups: rec.radio.amateur.antenna Subject: The Elmer HAMlet is moving... Date: Wed, 05 Jun 1996 00:01:35 -0400 Message-ID: <31B5069F.EC5@ix.netcom.com> The old address was... http://www.4w.com/ham/antenna Our new address is... http://qth.com/antenna 73-- AC3L From amsoft@epix.net Wed Jun 05 20:33:43 1996 From: moritz@ipers1.e-technik.uni-stuttgart.de () Newsgroups: rec.radio.amateur.antenna Subject: Re: Tonna Antennas Date: 2 Jun 1996 21:07:34 GMT Message-ID: <4osvqm$1jp2@info4.rus.uni-stuttgart.de> References: <31AF1DEC.4CA6@scdt.intel.com> Is their stuff any good? The quality is reasonable, they are a good buy for their money. There are surely better quality antennas around. 73, Moritz DL5UH From amsoft@epix.net Wed Jun 05 20:33:44 1996 From: jackl@pinetree.microserve.com (WB3U) Newsgroups: rec.radio.amateur.antenna Subject: Re: What's a good AM tuner? Date: Mon, 03 Jun 96 02:22:36 GMT Message-ID: <4otmid$2rr@crash.microserve.net> References: <4om63u$lrp@vixen.cso.uiuc.edu> <4omdde$e0s@dfw-ixnews3.ix.netcom.com> <31B275CA.7D43@worldnet.att.net> Cameron Hughes <1yardbird@worldnet.att.net> wrote: >Anthony Severdia wrote: >> How does your message (crossposted) relate to >>rec.radio.amateur.antenna? >> >> Bah humbug! >You're kidding, right? Okay, let me make it simpler. I like the >Kiwa antenna. What's a good AM tuner to put it on? > >Instead of the sarcastic reply, how about a little help? I think you missed his point. "Radio.Amateur" as it's used in the name of this newsgroup means ham radio. It doesn't have much to do with BCB AM receivers. Regards, Jack WB3U From amsoft@epix.net Wed Jun 05 20:33:45 1996 From: Cecil Moore Newsgroups: rec.radio.amateur.antenna Subject: Re: WTB ARRL book "Reflections" Date: 1 Jun 1996 14:11:03 -0700 Message-ID: <4oqbl7$j3n@nnrp1.news.primenet.com> References: <319BBC13.D2C@gorge.net> <4nnk86$nnp@chnews.ch.intel.com> <4o0phu$jgq@dfw-ixnews10.ix.netcom.com> <4o1rll$1io@nnrp1.news.primenet.com> armond@delphi.com wrote: : Cecil: "Reflections" will be published again by another publisher in the Ama teur : Radio field. I'll give you three guesses who and the first two don't count! : N6WR Armond, you know you will have to re-edit that book. Mr. Maxwell says the G5RV is a 102 ft *dipole* designed for 20m. :-) 73, Cecil, KG7BK (W6RCA soon), OOTC From amsoft@epix.net Sat Jun 08 13:00:06 1996 From: amsoft@epix.net Newsgroups: rec.radio.amateur.policy,rec.radio.amateur.misc,rec.radio.amateur.homebrew,rec.radio.amateur.equipment,rec.radio.amateur.dx,rec.radio.amateur.digital.misc,rec.radio.amateur.antenna Subject: ! June 96 CD-ROM Available ! Date: Thu, 06 Jun 96 20:37:35 PDT Message-ID: AmSoft announces the June 1996 release of its CD-ROM "The World of Ham Radio". This CD-ROM contains the World's largest collection of amateur radio, electronic, and engineering software, plus the most recent FCC amateur radio license database available on CD-ROM. The current FCC database includes calls issued up to 22 April 1996. This software collection is the best available anywhere in the World for electronics, engineering, and the hobby of Amateur Radio. Over 20,000 files and programs for the hobbyist or professional. Stop by our WWW SITE: http://hamster.ivey.uwo.ca:80/~amsoft/ and see. At $19.00 plus $4.00 Shipping anywhere in the World AmSoft has the lowest price for any CD-ROM offering these services. TELEPHONE: 717-938-8249 FAX: 717-938-6767 or send E-MAIL: amsoft@epix.net From amsoft@epix.net Sat Jun 08 13:00:07 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: 5/8 CB Ant Question Date: 6 Jun 1996 18:37:06 -0400 Message-ID: <4p7mii$bqb@newsbf02.news.aol.com> References: <4p6a7s$iq3@newsbf02.news.aol.com> In article <4p6a7s$iq3@newsbf02.news.aol.com>, kj4uo@aol.com (KJ4UO) writes: > >I measured the lenght of the antenna and it is 18 feet, this puts it at >the lenght of a 1/2 wave. The manufacturer states it is a 5/8 wave. The >base has a loading coil which is 12 turns with the fourth turn grounded >back to the outer conductor of the coax and radials. The question is how >can this be a 5/8 wave when the lenght is that of a 1/2 wave? How does >the loading coil working by grounding out the fourth turn from the base? > > Be glad that it is a 1/2 wl antenna, because a 5/8 wl doesn't have any more gain unless the groundplane is VERY LARGE, perhaps a few hundred feet across for ten meters. As a matter of fact, the 5/8 w can have less gain in real world conditions. 73 Tom From amsoft@epix.net Sat Jun 08 13:00:07 1996 From: jafl@msg.ti.com (Jim Flanders) Newsgroups: rec.radio.amateur.antenna Subject: Re: 6m antenna Date: 6 Jun 1996 16:04:06 GMT Message-ID: <4p6vhm$a9d@ganesh.mc.ti.com> References: <4p6l9v$3vm@news.innet.com> In article <4p6l9v$3vm@news.innet.com>, hamradio@camalott.com says... > >I would like to try out six meters on ssb and cw. What types of >antenna would work for this. Homebrew would be ok also. Thanks, >KC5OQE > One of my favorite 6 or 2 meter horizontal polorized antenna systems for general work is stacked big wheels. If you have a fax number, I will fax the patterns to build a big wheel. Jim W0OOG/5 147.180 in Plano, TX From amsoft@epix.net Sat Jun 08 13:00:08 1996 From: fedpress@omnifest.uwm.edu (Rick Kissell) Newsgroups: rec.radio.amateur.antenna Subject: Re: 6m antenna Date: 6 Jun 1996 11:17:03 -0500 Distribution: na Message-ID: <4p709v$11s@omnifest.uwm.edu> If you're thinking about getting on 6m, probably your smartest initial move would be to shell out 14 bucks for a (postpaid) copy of "Six Meters: A Guide to the Magic Band" by Ken Neubeck, WB2AMU. It's a very good introduction to the band for newcomers, and it has a chapter on antennas. The convention on 6m is vertical polarization for FM, and horizontal polarization for the other modes. However, during band openings, polarization really doesn't matter. (For example, over the past few weeks, I have worked from New Mexico to New Brunswick on 6m SSB using my Diamond brand 6m ground plane.) The book is available from: Worldradio Books Box 189490 Sacramento, CA 95818 You might also want to subscribe to the VHF DX e-mail reflector out of Stanford University: vhf-request@w6yx.stanford.edu 73, Rick WB9GYT Milwaukee, WI EN62ax From amsoft@epix.net Sat Jun 08 13:00:10 1996 From: Gene Marcus Newsgroups: rec.radio.amateur.antenna Subject: Re: 6MX eggbeater Date: Thu, 06 Jun 1996 23:09:41 -0500 Message-ID: <31B7AB84.1DFF@hiwaay.net> References: <4oibfo$l89@usenet.srv.cis.pitt.edu> Reply-To: mmarcus@hiwaay.net Adam VK3ALM writes: > Has anyone had any experience with eggbeaters, particularly on 6MX? > What's the performance like? > Any there any good articles you could make me aware of? I have built a number of eggbeater (loop turnstile) type antennas for 2 meters and 70 cm. The antennas are very good performers that exhibit omnidirection horiz ontal polarization at the horizon and circular polarization overhead. A very intere sting review of the M2 eggbeaters appeared in the Sptember 1993 QST. I have used my homebrew loop turnstiles for low earth orbit digital satellite, terrestial ssb, and ATV communications with good results. I have also built a stacked array of four 70 cm loop turnstiles to replace an Alford slot antenna on our local ATV in-band repeater. Eggbeaters are surprisingly easy to build. The antenna consists of two perpendiculary mounted full wavelength loops feed in phase quadrature. I feed one loop with a quarter wavelength of RG62 (93 ohm) coax used as a 90 degr ee delay line. I believe M2 uses lumped components to introduce reactance in seri es with one of the loops. The terminal impedance of each loop is approximately 120 ohm s, therefore, the delay line and remaining loop may be fed in parallel resulting in a good match to 50 ohms. The dimensions for the 70 cm loop turnstile are as follows: wire loops (2) - 28 inches #12 solid vinyl covered electrical wire 90 degree delay line - 5.8 inches RG-62 coaxial cable (93 ohm - velocity fact or 0.86) I used a 1 inch PVC pipe to support the loops. To change the circular polariz ation sense, simply move the feedpoint to the opposite side of the delay line. I have not built a six meter version of this antenna, but it would be a simple exercise to recalculate or rescale my dimensions. Hope this helps. 73... Gene W3PM GM4YRE Huntsville, AL w3pm@amsat.org From amsoft@epix.net Sat Jun 08 13:00:10 1996 From: Rick Miller Newsgroups: rec.radio.amateur.antenna Subject: Antenna for 11m fox hunt? Date: Mon, 3 Jun 1996 13:30:17 -0500 Message-ID: Reply-To: rdmiller@execpc.com What kind(s) of antennae might be good for a fox hunt in the FM Broadcast Band (88-108 MHz)? I'm especially looking for something that would be simple enough to make without too much expense, but functional enough to actually find the fox. What kinds of attenuators might be easily used by people who aren't (yet) into amateur radio? I know that doing it by ear (rather than a signal strength meter) isn't the best way to go about it, but I'm aiming for a low-budget hunt. If the broadcast doesn't cover a large enough area to make it interesting, might I use the Citizens' Band? Practically any kid I know can come up with a CB channel-14 walkie-talkie. Any ideas or suggestions would be appreciated. Rick Miller From amsoft@epix.net Sat Jun 08 13:00:12 1996 From: n0nas@hamlink.mn.org (Doug Reed) Newsgroups: rec.radio.amateur.antenna Subject: Antennas Message-ID: <833620193.AA06508@hamlink.mn.org> Date: Sat, 01 Jun 1996 09:16:55 -0100 to: pmackowi@ugrad.ug.cs.oz.au PM>What are the basics of antenna design? Hi Peter. That's a pretty open ended question and could never get a very straight answer. But here are a couple of my rules-of-thumb: The most basic antenna is the half-wave dipole, center fed. The approximate length is 5904/frequency (MHz) = inches. This is the same as 150/frequency (mHz) = meters. A dipole is the easiest standard of comparison for other antennas. Considering only properly designed and built antennas, the bigger the better and the smaller the worse. An antenna smaller than a physical half-wave (or quarter-wave) antenna will not work as well as the full size article. When making big antennas you have to double the size each time you want double the performance. If you are intending to DESIGN some antennas, get yourself a copy of the ARRL Antenna Book and study it. The answers to just about any question you have will be in there. For just starting out and playing with beam antenna designs, I've found YAGIMAX 3.11 to be a good program to get me in the ballpark although I'm going to have to try NEC for multi-band designs. Versions of NEC are the standard of comparison for design programs but is more complex to use and slower to run. If you just want to BUILD an antenna, find any book or magazine article that has what you want and get started. Then, when you are all done, get the ARRL Antenna Book and study it to find out what you built and why it works or doesn't. I've also found some good stuff in the RSGB Handbooks. The RSGB books compliment the ARRL books quite well. This is about all I'll give you based on your question. If you want a better answer, we'll need a better question. Good luck. Doug Reed, N0NAS email: n0nas@hamlink.mn.org St Paul, MN, USA * SLMR 2.1a * All wiyht. Rho sritched mg kegtops awound? From amsoft@epix.net Sat Jun 08 13:00:13 1996 From: mcewenjv@songs.sce.COM (JAMES MCEWEN) Newsgroups: rec.radio.amateur.antenna Subject: Antennas (Part II) Date: 7 Jun 96 15:43:27 GMT Message-ID: <9605078341.AA834158766@ccgateout.songs.sce.com> Subject: Antennas (Part II) Keith A Monahan wrote: > I am using a dual-band handheld transceiver. I am interested in > operating on all bands that my radio can. In brief, 108-128mhz, 140-170mhz, > 440-470mhz, and 800-999mhz. Obviously, I am operating locally, no DX contac ts > or anything like that. > > I recently purchased a Comet SH-55 16" whip. I am not sure if this > is appropriate for use on the bands I've mentioned. > (Technical thought)It seems that some people missed the obvious, from the frequency description this seems to be a scanner, and I doubt that it has transmit capabilities on all these frequencies, if any transmit capability at all. (Political thought!) I think it would be better for the mail list/newsgroup (and ham radio) if people were politely encouraged to get a ham license and continue their study of electronics beyond the minimum required for the FCC test. Trying to be a moral policeman makes you look like a crabby old man from Cape Cod. Jim KA6TPR Disclaimer: The views stated above may not reflect the position of my employer or other right wing groups, nor be politically correct when viewed in the light of left wing rhetoric. From amsoft@epix.net Sat Jun 08 13:00:14 1996 From: "Ken Bessler (KG0WX)" Newsgroups: rec.radio.amateur.antenna Subject: Re: Antennas (Part II) Date: Wed, 05 Jun 1996 15:00:18 -0500 Message-ID: <31B5E752.6416@southwind.net> References: <4ovf2u$5hs@usenet.srv.cis.pitt.edu> <31B4E7CF.1716@southwind.net> <4p3vbd$ovh@usenet.srv.cis.pitt.edu> <4p4ji1$l0n@nadine.teleport.com> To: Roy Lewallen Roy Lewallen wrote: > > Alas, Ken was being too subtle. Keith, it seems from your post that you > have no license to transmit on the frequencies you quoted. Hams in general > are reluctant to help anyone transmit illegally. We have enough trouble as > it is with unlicensed operators without helping them out. Consequently, I > don't think you'll get much help in this newsgroup, but it doesn't have > anything to do with your lack of experience -- just your lack of a license > to legally transmit. > > Roy Lewallen, W7EL Boy are you right, Roy! Here is what this little bootlegger sent me in the mail: Quote: #1> Then do not respond at all to the post. #2> "who appears to be bootlegging" I do not bootleg. I do NOT transmit on *any* frequency. 'Cept maybe 46/47mhz when I talk on my phone. Do not assume anything. I did NOT ask you to assist me in doing something illegal. As a matter of fact I spoke with a few members of the ARRL, who were more than happy to provide the information I required. I highly doubt the ARRL would aid or abet in a crime. Take your hypotheses elsewhere. Unquote. Here was my response: You DID mention transmitting in your original post: quote: "Whenever I say effective, I mean getting decent reception and decent transmitting ability. For instance, would a smaller antenna receive signals more clearly than my 16" whip at 440mhz?" unquote I shall not assist you in illegal activity. You have already indicated that you intend to use the information gathered by your request to do so. When and if you ever get a license, I will welcome you to the amateur fraternity. Until then I will not make myself liable by assisting you. -- Ken Bessler KG0WX Design Services Company http://www2.southwind.net/~kg0wx Model railroad designing From amsoft@epix.net Sat Jun 08 13:00:15 1996 From: jhhall@ucdavis.edu (Jeff Hall) Newsgroups: rec.radio.amateur.antenna Subject: Beam vs dipole at low height Date: Thu, 06 Jun 1996 00:01:14 GMT Message-ID: <4p579c$eki@mark.ucdavis.edu> First of all I know that the higher the better...I hate looks of antennas. so my question is. If I put a 20/15/20 meter beam only on the top of the peak of my single story house am I wasting my time and money..If I don't do that I have two other plans: Butternut vertical at ground level or a dipole up 20 feet. Would the beam do me that much good at being just at house peak level..thanks for your time..Jeff From amsoft@epix.net Sat Jun 08 13:00:16 1996 From: "John T. Young" Newsgroups: rec.radio.amateur.antenna Subject: Re: Beam vs dipole at low height Date: Fri, 7 Jun 1996 08:23:11 -0700 Message-ID: References: <4p579c$eki@mark.ucdavis.edu> To: Jeff Hall Jeff, I just went from a dipole to a Moseley beam (TA33JR WARC) at 38'. The change was incredible. I kept the dipole up for comparisons for several days. In reception, the beam gave me a 5 s-unit improvement! Same with transmission. By all means get the beam. Best, John, KI7JB. On Thu, 6 Jun 1996, Jeff Hall wrote: > First of all I know that the higher the better...I hate looks of > antennas. so my question is. If I put a 20/15/20 meter beam only on > the top of the peak of my single story house am I wasting my time and > money..If I don't do that I have two other plans: Butternut vertical > at ground level or a dipole up 20 feet. Would the beam do me that much > good at being just at house peak level..thanks for your time..Jeff > > > From amsoft@epix.net Sat Jun 08 13:00:16 1996 From: cmoore@vegas.ch.intel.com (Cecil A. Moore~) Newsgroups: rec.radio.amateur.antenna Subject: Re: Beam vs dipole at low height Date: 7 Jun 1996 18:00:44 GMT Distribution: world Message-ID: <4p9qoc$16uo@chnews.ch.intel.com> References: <4p579c$eki@mark.ucdavis.edu> In article , John T. Young wrote: >Jeff, I just went from a dipole to a Moseley beam (TA33JR WARC) at 38'. >The change was incredible. I kept the dipole up for comparisons for >several days. In reception, the beam gave me a 5 s-unit improvement! Same >with transmission. By all means get the beam. Best, John, KI7JB. Hi Jeff, that means your beam has a gain somewhere between 15 and 30 dBd. That is a little too incredible. 73, Cecil, KG7BK, OOTC (not speaking for my employer) From amsoft@epix.net Sat Jun 08 13:00:18 1996 From: gray@news.humberc.on.ca (Kelly Gray) Newsgroups: rec.radio.amateur.antenna Subject: Re: Bicycle Moble Dual Band J-pole Date: 2 Jun 1996 01:06:56 GMT Message-ID: <4oqpfg$dkq@dns.humberc.on.ca> References: <31a69ab2.14599252@news.interport.net> <4oaubn$q0g@newsbf02.news.aol.com> <31AF853D.7D06@mindspring.com> Paul Davis (paul1@mindspring.com) wrote: : I read the previous posts about the dual band j-pole with interest. : However, I am looking for somthing to mount on a bicycle. The : 300ohm twin lead sounds like it would do the trick. Would I need a : diplexer or somthing to use two antennas? BTW the bands in question are : 2m and 70cm. : -- : Paul Davis : paul1@mindspring.com : http://www.mindspring.com/~paul1/ I too am looking for an antenna to mount on my bicycle, although I'd be satisfied with a single band 2m version. The problem with the twinlead J-Pole is that it is VERY sensitive to changes in the material near the lower part of the J. Even placing it up against a wooden surface is enough to seriously detune the antenna! It has been suggested that I could just stick a standard mag-mount on my rear carrier, but that's where I ususally carry my cargo (backpack full of books etc) so I have no room there. so far, the best idea I can come up with is to bury a coax dipole inside a fibreglass whip. Anyone know where I might be able to obtain a 6ft hollow whip? I'd even be willing to tolerate the high losses and use RG-174 cable for the antenna itself if I could find a whip to fit it in. 73 de ve3vgp Kelly Gray From amsoft@epix.net Sat Jun 08 13:00:19 1996 From: w7el@teleport.com (Roy Lewallen) Newsgroups: rec.radio.amateur.antenna Subject: Re: Bobtail Curtain - Gain Versus Feedpoint Date: Thu, 06 Jun 96 10:23:57 GMT Message-ID: <4p6bib$ir6@nadine.teleport.com> References: <4p2aki$q25@mtinsc01-mgt.ops.worldnet.att.net> <4p4fsj$rju@mtinsc01-mgt.ops.worldnet.att.net> <833998123snz@microvst.demon.co.uk> <4p544m$3bs@mtinsc01-mgt.ops.worldnet.att.net> In article <4p544m$3bs@mtinsc01-mgt.ops.worldnet.att.net>, >Roy, if you don't mind posting it here, what is the difference between >EZNEC and ELNEC with regard to ground and radials? Ground is used for two separate purposes by both programs. The first is in determining the antenna impedances and currents. Once the currents are determined, the radiated field is calculated. A direct ray is added to the ray reflected from the ground to find the radiation pattern. Determination of the strength and phase of the reflected signal is the second use of the ground model. MININEC (hence, ELNEC) always assumes that the ground is perfect for the impedance and current calculation. This is a good approximation for vertical wires and for horizontal wires higher than about 0.2 wavelength. NEC-2 (hence EZNEC) also has reflection-coefficient and Norton-Sommerfeld ground calculation methods. The former permits accurate modeling with horizontal wires down to about 0.1 wavelength; the latter, down to about 0.001 wavelength. As implemented in NEC-2 and EZNEC, neither permits modeling of buried wires or structures, so none of the methods gives an accurate picture of losses in buried ground systems. MININEC and NEC-2 (and ELNEC and EZNEC) use the same general method of ground reflection coefficient calculation to determine the field reflected from the ground in determining the radiation pattern. All programs also use the same general method for modeling radials. The average conductivity of the wires at a given distance from the antenna is put in parallel with the ground conductivity, and the combination used to determine the reflection coefficient for pattern calculation. The radial model isn't used for impedance or current calculation. The wires are "smeared" over the ground, so to speak, so there's no consideration of which direction they're actually pointing. Nor is there any consideration of nonuniform current distribution on them, or end effects. I've run a few tests of the radial model against a model with actual buried wires using NEC-4, which does model buried wires, and found rather poor agreement. I'm sure that the models agree better in some circumstances than others, but I haven't determined which. I recommend against putting much faith in the radial model, and force EZNEC users to set an environment variable to enable the radial model in the hopes that in looking in the manual to figure out how, they'll read about the limitations of the model. Roy Lewallen, W7EL From amsoft@epix.net Sat Jun 08 13:00:20 1996 From: Cecil Moore Newsgroups: rec.radio.amateur.antenna Subject: Re: Bobtail Curtain - Gain Versus Feedpoint Date: 7 Jun 1996 07:02:01 -0700 Message-ID: <4p9cop$ikp@nnrp1.news.primenet.com> References: <4p78fa$ie5@nnrp1.news.primenet.com> <4p8rsq$pli@newsbf02.news.aol.com> W8JI Tom wrote: : My 40 meter dipole at 85 feet easily beats a 1/4 wl vertcal on 40 most of : the time. : A dipole I had at 350 feet easily beat my 1/4 wl vertical on 160. Thanks Tom, let me rephrase the question. Why would anyone spend good money for an all-band HF vertical when a dipole will outperform it on all bands except 75m? Have you looked at the atrocious prices on 0 dBi store-bought verticals? -- 73, Cecil, KG7BK (W6RCA soon), OOTC From amsoft@epix.net Sat Jun 08 13:00:21 1996 From: pricemw@aol.com (Pricemw) Newsgroups: rec.radio.amateur.antenna Subject: Re: DDRR Date: 6 Jun 1996 16:27:27 -0400 Message-ID: <4p7evf$8c3@newsbf02.news.aol.com> Reply-To: pricemw@aol.com (Pricemw) Jim....WD5OOG writes: >This Last weekend - compared signal strengths between a Texas Bug >Catcher - and a DDRR. The DDRR was close to 6 DB more signal at >.3 miles from the antenna. I then modified the DDRR upon the >suggestion of one of the threads. The modification was to raise the >height of the DDRR above the ground plane. As I did this, the vertical >component of the signal was reduced and horizontal component began to >appear. (With the DDRR 11" above the ground plane, the horizontal >component was -20 Db below the vertical component.) As I continued >to raise the height the horizontal component became stronger until >the height was four feet. At this point the horizontal comp. was +8.5 >Db greater than the vertical, and the radiation angle was 66 degrees. > I have gone back to the classical DDRR design where almost all the >radiation is vertical, and the vertical pattern peaks at 16 degrees. > My conclusion is: - Even though the antenna looks like a top >loaded vertical laid down on a ground plane - Electrically it is a >slot antenna when (and ONLY WHEN) it is very close to the ground plane. >As soon as I moved the radiator away from the ground plane, it did >start to a loaded vertical. Very interesting....I assume the tests were performed at 75/80 meters. What was the construction of the DDRR....copper pipe, tailpipe, etc. ...and the ground was...chicken wire, copper wire, etc? How would you account for more vertical radiation when the vertical part is shortest? Is there any Brewster effect involved? --Wayne W5GIE in Redlands, CA From amsoft@epix.net Sat Jun 08 13:00:22 1996 From: pricemw@aol.com (Pricemw) Newsgroups: rec.radio.amateur.antenna Subject: Re: DDRR antenna - Test Results Date: 6 Jun 1996 18:38:46 -0400 Message-ID: <4p7mlm$brb@newsbf02.news.aol.com> References: <4p49i3$teb@ganesh.mc.ti.com> Reply-To: pricemw@aol.com (Pricemw) Jim WD5OOG writes: >This Last weekend - compared signal strengths between a Texas Bug >Catcher - and a DDRR. The DDRR was close to 6 DB more signal at >.3 miles from the antenna. I then modified the DDRR upon the >suggestion of one of the threads. The modification was to raise the >height of the DDRR above the ground plane. As I did this, the vertical >component of the signal was reduced and horizontal component began to >appear. (With the DDRR 11" above the ground plane, the horizontal >component was -20 Db below the vertical component.) As I continued >to raise the height the horizontal component became stronger until >the height was four feet. At this point the horizontal comp. was +8.5 >Db greater than the vertical, and the radiation angle was 66 degrees. > I have gone back to the classical DDRR design where almost all the >radiation is vertical, and the vertical pattern peaks at 16 degrees. > My conclusion is: - Even though the antenna looks like a top >loaded vertical laid down on a ground plane - Electrically it is a >slot antenna when (and ONLY WHEN) it is very close to the ground plane. >As soon as I moved the radiator away from the ground planoaded vertical. >Jim W0OOG/5 147.180 and 14.243 @ 11:30 CST (subvets net) Jim-- Very interesting test results. You should consider an article. I have a few questions: 1. I assume the test was done on 75/80 meters? 2. How "good" was the DDRR construction? Was copper pipe, or auto tailpipe used for the radiating element? Was the ground "chicken wire" or copper radials? etc,etc 3. How do you account for a shorter vertical height producing a larger vertical component? --Wayne W5GIE in Redlands, CA From amsoft@epix.net Sat Jun 08 13:00:23 1996 From: n0nas@hamlink.mn.org (Doug Reed) Newsgroups: rec.radio.amateur.antenna Subject: Design For 1/4 wave z xfm Message-ID: <834131563.AA06560@hamlink.mn.org> Date: Fri, 07 Jun 1996 07:50:13 -0100 to: pmarkham@sun.lssu.EDU PM> Looking for a real world design/ideas for 1/4 wave coaxial PM>linetransformers Pete/wa4hei . I ran across an article in June 1994 QST, "The World Above 50 MHz" column. It talks about using 75 ohm CATV hardline on VHF/UHF and references March 1988 QEX for one article on building matching sections and also mentions W8ZD as one manufacturer of matching sections. This is the company I was thinking of. Matching sections were about $35 to $40 for the pair from ZD Engineering, 605 Balsey Ave, Findlay, OH, 45840, phone 419-424-8765. (Address & phone from 6/94 QEX article.) The ATVQ magazine articles I mentioned must have been from around the same time. 73's. Doug Reed, N0NAS email: n0nas@hamlink.mn.org * SLMR 2.1a * --T-A+G-L-I+N-E--+M-E-A+S-U-R+I-N-G+--G-A+U-G-E-- From amsoft@epix.net Sat Jun 08 13:00:23 1996 From: unitogh@hondutel.hn (UNITOG) Newsgroups: rec.radio.amateur.antenna Subject: Easy and Efficient Wire Antenna For 160M? Date: 7 Jun 96 18:26:35 GMT Message-ID: <199606071435.OAA01792@miraf-server2.hondutel.hn> Has any one tried a wire antenna as described in the Arrl Antena Book, 14th Edition, page 8-8? It has one vertical and one horizontal 30' radiator and it's elevated feed point is fed with ladder line. The text claims high efficiency on both 40m & 80m. "Higher than it would be for a ground plane"!!! Sounds too good to be true. What can be expected if both radiators are 60' for 160m? HR3TFD Todd DeWire unitogh@hondutel.hn From amsoft@epix.net Sat Jun 08 13:00:24 1996 From: Bill Kleronomos Newsgroups: rec.radio.amateur.antenna Subject: Feeding Vertical with Balanced Line? Date: 7 Jun 1996 03:10:12 GMT Message-ID: <4p86ik$4dc@news-2.csn.net> Greetings, fellow Sons of Marconi! Having recently bought the 'lot in the sticks' I'm going through the iterations of various antenna designs. One configuration involves a 160/80/40 meter band ground mounted bottom fed vertical (90 feet tall)working against the usual radial ground system. Since the antenna will be some 500 feet from the shack and I'd like to avoid remotely operated motor driven matching components I'm thinking about just feeding the thing with some stout open wire line with the ATU in the shack. Since the antenna could be classified as unbalanced, I'm looking for comments re: feeding the thing with a balanced line- like about line radiation, etc. Howzabout feeding the thing with a hi-voltage rated balun between the line and antenna- necessary? Needless to say, the line VSWR is gonna be horrible from band to band. Thanks- Bill, KD0HG Lyons, Colo. From amsoft@epix.net Sat Jun 08 13:00:25 1996 From: Edward Oros Newsgroups: rec.radio.amateur.antenna Subject: Field day antennas... Date: Sat, 01 Jun 1996 20:45:13 -0400 Message-ID: <31B0E419.B0A@ix.netcom.com> Are you ready for field day yet? It's just a couple of weeks away! Now you can design your own QUAD, Ground Plane, Dipole or Inverted Vee at http://www.4w.com/ham/antenna Come and visit today. Ed -- AC3L From amsoft@epix.net Sat Jun 08 13:00:26 1996 From: jeffa@ix.netcom.com(Jeff Anderson) Newsgroups: rec.radio.amateur.antenna Subject: Re: G5RV TVI Date: 5 Jun 1996 12:41:04 GMT Message-ID: <4p3v90$9dt@dfw-ixnews2.ix.netcom.com> References: <4p2rgu$rgu@ram2.ramlink.net> <31B52E26.7A05@snet.net> In <31B52E26.7A05@snet.net> N1SQJ writes: > >Tom wrote: >> >> I just installed the G5RV antenna. I am now experiencing >> heavy TVI and Telephone interference when on both >> 80 and 40 meters. I am using a MFJ 945 tuner to bring >> the SWR down to 1 to 1. I would like to hear from anyone >> else that is experiencing the same problem and what steps were >> taken to fix the problem. Notes: my tuner is not grounded, my >> tv is on cable tv, >> . There may be nothing that you can do at your antenna end, other than moving it far far away from the telephone(s) in question. It's possible that the G5RV's RF field pattern is stronger at the telephone/TV than the other antenna you had been using. Many modern phones have all kinds of electronic critters inside them that act as non-linear devices to strong RF fields. You may need to filter both the handset cable and the telephone cable where they enter the phone (and if there's a DC power source, you should filter that too). The house power-wiring may also be acting as an antenna, and this is how, perhaps, the cable TV is being affected. - Jeff, WA6AHL From amsoft@epix.net Sat Jun 08 13:00:27 1996 Newsgroups: rec.radio.amateur.antenna From: root@jackatak.theporch.com (Jack GF Hill) Subject: Re: G5RV TVI Date: Wed, 5 Jun 1996 13:21:05 GMT Message-ID: References: <4p2rgu$rgu@ram2.ramlink.net> tomg@mail.ramlink.net (Tom ) writes: > I just installed the G5RV antenna. I am now experiencing > heavy TVI and Telephone interference when on both > 80 and 40 meters. You do not say exactly how your feedline is managed... are you using the "classic" G5RV design with ladderline connected to coax before the tuner? Ladderline all the way to the tuner? > I am using a MFJ 945 tuner to bring the SWR down to 1 to 1. This also may be the problem... not the MFJ, but the design of the tuner... problem here is that the tuner uses three tuning components (input coupler capacitor, output tuner capacitor, and inductor) and there are really only two "equations" to solve these three "unknowns" What this means is that this tuner design has "imaginary" solutions -- imaginary in the mathmatical sense -- that give you false readings of SWR and result in unbelievably bad harmonic suppression and spurrious radiation because the system simply isn't tuned at all! The G5RV was built to be optimized on 20 meters, and offered reasonable matches on other bands, due mostly to the losses in feedline configuration... Perhaps you could give us a bit more *data* to go on... > Notes: my tuner is not grounded, my tv is on cable tv, I don't think that the failure to ground your tuner is the entire problem, though you really should have a single point of grounding for the entire shack and *system*... it is for your own protection and safety, and it won't negatively impact performance... Is the interference ONLY on your own TV? I just caught the implication... if so, then the problem may well be with the set design... How about you give us a bit more data to work with? -- 73, Jack, W4PPT/M (75M SSB 2-letter WAS #1657/#1789 -- both from the mobile! ;^) +--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--+ | Jack GF Hill |Voice: (615) 459-2636 - Ham Call: W4PPT | | P. O. Box 1685 |Modem: (615) 377-5980 - Bicycling and SCUBA Diving | | Brentwood, TN 37024|Fax: (615) 459-0038 - Life Member - ARRL | | root@jackatak.theporch.com - "Plus ca change, plus c'est la meme chose" | +--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--+ From amsoft@epix.net Sat Jun 08 13:00:30 1996 From: Samuel Geller Newsgroups: rec.radio.amateur.antenna Subject: H A M F E S T and Computer Fest Date: Sat, 8 Jun 1996 09:57:33 -0400 Message-ID: ------------------------------------------------------------------ | The Famous BRATS Maryland | | | | H A M F E S T and C O M P U T E R F E S T | | | | Sunday July 28, 1996 | | | | At the Maryland State Fairgrounds, Timonium, MD | | (On York Road, just North of the Baltimore Beltway (695)) | | | | Air Conditioned Building LARGE Tailgating Area | | | | Plenty of Free Parking | | Accessible to the Handicapped | | For Information, or table reservations, call (410)467-4634 | | OR brats@smart.net OR our home page: http://smart.net/~brats | | | | Talk-in on the BRATS Repeater System 147.030(+) and 224.960(-) | ------------------------------------------------------------------ From amsoft@epix.net Sat Jun 08 13:00:30 1996 Newsgroups: rec.radio.amateur.antenna From: Bob Lewis Subject: Re: Help! High SWRs Message-ID: <31B80EBA.760B@staffnet.com> Date: Fri, 07 Jun 1996 07:12:58 -0400 References: <4ouari$lo6@newsbf02.news.aol.com> To: Decibel7 Decibel7 wrote: > > Greetings, > > For lack of a base station I have tried mounting an antenna on top of a > Pole in the ground (ground wired at top) and running the coax into my car > to the radio. The SWR is around 4-infinite. > > Is the grounding of one end to ground and the other to vehicle ground the > problem? > > If so how do I fix this? > > If not, what is it and how do I fix it? > > Good speed to your modem > Decibel7 If it's a typical mobile whip antenna you a talking about then the problem is lack of radials when it's mounted on the pole. You'd be better off with a dipole or some other balanced antenna on the pole. 73, Bob (AA4PB) From amsoft@epix.net Sat Jun 08 13:00:31 1996 From: Brian00@cris.com (Brian Jones) Newsgroups: rec.radio.amateur.antenna Subject: Re: HF antenna for apartment Date: 2 Jun 1996 19:56:52 GMT Message-ID: <4osrm4$1tr@tribune.concentric.net> References: <31AB3CF5.1BB@comm.hq.af.mil> Vincent D'Elia, Jr (deliav@comm.hq.af.mil) wrote: : I'm thinking of putting my hf on the air and was wondering I should use : as a antenna. : I'm using aYeasu FT-901 and a MFJ tuner : Any suggestions? : Vince : KC6ISS Hi Vince, I use a B&W AP-10 at my apartment. It is only $70 and comes with coils to enable its use on 40 through 2 meters. It is a simple vertical that is base loaded and uses a counterpoise to match it. I cant compete with the big boys but I have worked some DX only using 100 watts. AES sells it, BTW. I have it mounted on my balcony using bent coat hangers. Later tonight when I am done I'll take it down. Works great for $70. Brian AC5GL From amsoft@epix.net Sat Jun 08 13:00:32 1996 From: tomb@lsid.hp.com (Tom Bruhns) Newsgroups: rec.radio.amateur.antenna Subject: Re: Is RG-389/U (military stuff) Any Good ? Date: 6 Jun 1996 18:20:00 GMT Message-ID: <4p77gg$br2@hpcvsnz.cv.hp.com> References: <4p6ghh$31u@buffnet2.buffnet.net> david james (daveb@buffnet.net) wrote: : Greetings, : Came across some military surplus coax recently. It is labled : RG-289/U. : Uses humongo connectors but N adapters are available. Lengths are 40'. Is it 289 or 389? dB/100 ft: 10MHz 100MHz 400MHz 1000MHz RG-289/U .04 .15 .30 .50 RG-389/U .20 .70 1.50 2.50 -- Cheers, Tom tomb@lsid.hp.com From amsoft@epix.net Sat Jun 08 13:00:33 1996 From: Cecil Moore Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.homebrew Subject: Re: need help with wire dipole Date: 4 Jun 1996 20:01:02 -0700 Distribution: world Message-ID: <4p2t9e$jcr@nnrp1.news.primenet.com> References: Brian Olliver wrote: : -i don't think a full wave dipole will radiate "check it out" : maximum voltage will be at the centre of the half conductors : thus cancelling each other- Hi Brian, just because maximum voltage occurs at the center of a dipole doesn't mean it won't radiate (unless, of course, one is using coax to feed it directly. :-) One of the very interesting things about 450 ohm ladder-line is that the SWR will be the same when feeding a 45 ohm half-wave dipole and when feeding a 4500 ohm full-wave dipole. That means that the SWR is somewhat consistent when using 450 ohm ladder-line so it really doesn't make any difference what the length of the dipole is (as long as it doesn't go below approximately 3/8 WL). -- 73, Cecil, KG7BK (W6RCA soon), OOTC From amsoft@epix.net Sat Jun 08 13:00:34 1996 From: David Rice Newsgroups: rec.radio.amateur.antenna Subject: Plans needed for 1296MHZ vertical Date: Fri, 31 May 1996 10:39:38 -0700 Message-ID: <31AF2ED9.467D@wsi.net> Reply-To: dave@wsi.net Does anyone have any plans for building a 1296MHZ vertical? Hopefully some type of colinear. I have many plans for directional antennas, but would like a simple vertical design for working local FM repeaters. Please E-mail me any designs. Thanks! From amsoft@epix.net Sat Jun 08 13:00:35 1996 From: macino@mail.fwi.com Newsgroups: rec.radio.amateur.antenna Subject: VHF and UHF antennas at airports for ATC Date: 4 Jun 1996 19:42:00 GMT Message-ID: <4p23i8$ndg@news.fwi.com> Reply-To: macino@mail.fwi.com Howdy, I couldn't tag on to the original post. The guy you want to get a hold of is Donald Madison KB9IHT. He has been the builder/supplier of these antennae for years. He isn't on the net, and is seldom on the air, but 'knows his stuff' Jim WD9AHF From amsoft@epix.net Sat Jun 08 13:00:36 1996 From: jjmartin@shore.net (JJ Martin) Newsgroups: rec.radio.amateur.antenna Subject: Re: vhf and uhf antennas at airports for atc Date: Thu, 06 Jun 1996 15:27:37 GMT Message-ID: <4p6mca$ce6@shore.shore.net> References: <31B1EB90.7451@bmts.com> <19960602.223744.78@southlin.demon.co.uk> Reply-To: jjmartin@shore.net graham@southlin.demon.co.uk (Graham Seale) wrote: >In message <31B1EB90.7451@bmts.com> Darran Bogden wrote: >> Can anyone tell me where I can find information on the vhf and uhf >> antennas used at major airports and air traffic control facilities? >> >> The ones I've seen at most airports look like a ground plane antenna, >> with four thin elements pointing down at about a 60 degree angle, with >> a single, much thicker (pipe?) vertical element pointing up. (Is the >> pipe the antenna, or is there something else in there?) The uhf ones >> are much smaller of course, but of the same design. Although they may have changed a lot in the last 10 years or so, discone type antennas were employed frequently...at least on the military UHF frequencies. Vertical type "popsicle" antennas were used for VHF a lot too during the 13 years I was a USAF air traffic controller. =========================================== cheers! jim martin, wk1v lowell, mass http://www.shore.net/~jjmartin/jjm.htm From amsoft@epix.net Sat Jun 08 13:00:37 1996 From: jjmartin@shore.net (JJ Martin) Newsgroups: rec.radio.amateur.antenna Subject: Re: vhf and uhf antennas at airports for atc Date: Fri, 07 Jun 1996 16:38:27 GMT Message-ID: <4p9esq$j6t@shore.shore.net> References: <31B1EB90.7451@bmts.com> <19960602.223744.78@southlin.demon.co.uk> <4p6mca$ce6@shore.shore.net> <4p7gfl$f32@news.jf.intel.com> Reply-To: jjmartin@shore.net jgarver@ichips.intel.com (Jim Garver) wrote: >I hate discones. They seem to shoot the energy down, opposite of a >1/4 wave ground plane antenna. Maybe good for a hilltop. I don't believe these antennas were used by ATC for DXing purposes. They worked well at line of sight...they appeared to anyway. Occasionally we'd have the morning and evening enhanced conditions and we'd get our radio checks with other ATC facilites when we could work 'em. =========================================== cheers! jim martin, wk1v lowell, mass http://www.shore.net/~jjmartin/jjm.htm From amsoft@epix.net Sat Jun 08 13:00:38 1996 From: Maude Schyffert Newsgroups: rec.radio.amateur.antenna Subject: Re: WTB Full size 3/4 el 17m & 40 yagi beams Date: Thu, 06 Jun 1996 12:58:28 -0700 Message-ID: <31B73864.3039@mailbox.swipnet.se> References: <4p41cd$sba@nntp.igs.net> Reply-To: maude.schyffert@mailbox.swipnet.se Stan Sanderson wrote: > > Hi & thanks for reading this. I want to but a full size 40 m and 17 m > beams. I prefer 4 element but 3 el maybe ok. Stan Sanderson VA3DS, > Bainsville, Ont. CANADA > email: dss@cnwl.igs.net Good idea, Just get an antenna handbook and read. Good luck / SM0BKZ From amsoft@epix.net Sat Jun 08 13:00:39 1996 From: dss@cnwl.igs.net (Stan Sanderson) Newsgroups: rec.radio.amateur.antenna Subject: WTB Full size 3/4 el 17m & 40 yagi beams Date: Wed, 05 Jun 1996 13:08:23 GMT Message-ID: <4p41cd$sba@nntp.igs.net> Hi & thanks for reading this. I want to but a full size 40 m and 17 m beams. I prefer 4 element but 3 el maybe ok. Stan Sanderson VA3DS, Bainsville, Ont. CANADA email: dss@cnwl.igs.net From amsoft@epix.net Sat Jun 08 13:00:39 1996 From: "G. Keown" Newsgroups: rec.radio.amateur.antenna Subject: WTB: Tower Date: Tue, 04 Jun 1996 20:05:32 -0500 Message-ID: <31B4DD5C.59CC@io.com> Interested in buying a used (but in good condition) 40-50 ft. tower with a top section. Prefer Rohn 25 or similiar. Reasonably priced. Prefer the Austin or central Texas area so I can pick-up. Contact me via E-Mail From amsoft@epix.net Fri Jun 14 11:52:43 1996 Newsgroups: rec.radio.amateur.antenna From: Bruce Fanker Subject: (no subject) Message-ID: Date: Wed, 12 Jun 1996 18:00:11 GMT From amsoft@epix.net Fri Jun 14 11:52:44 1996 Newsgroups: rec.radio.amateur.antenna From: Bob Lewis Subject: Re: 6m antenna Message-ID: <31BD66AE.6775@staffnet.com> Date: Tue, 11 Jun 1996 08:29:34 -0400 References: <4p6l9v$3vm@news.innet.com> To: hamradio@camalott.com hamradio@camalott.com wrote: > > I would like to try out six meters on ssb and cw. What types of > antenna would work for this. Homebrew would be ok also. Thanks, > KC5OQE Horizontally polarized. A beam is best. A horizontal loop (halo, sqalo, etc) will do. Stay away from verticles. 73, Bob (AA4PB) From amsoft@epix.net Fri Jun 14 11:52:45 1996 Newsgroups: rec.radio.amateur.antenna From: bb840@scn.org (James Aeschliman) Subject: Re: 6m antenna Message-ID: Reply-To: bb840@scn.org (James Aeschliman) References: <4p6l9v$3vm@news.innet.com> Date: Mon, 10 Jun 1996 18:40:29 GMT In a previous article, hamradio@camalott.com () says: >I would like to try out six meters on ssb and cw. What types of >antenna would work for this. Homebrew would be ok also. Thanks, >KC5OQE > For "trying out" I would stay with something simple and put up a simple 6 meter dipole. Check an ARRL Handbook for the standard formula for length and have fun. If things get serious, then look into a better antenna. -- Jim Aeschliman bb840@scn.org Black Diamond, Washington KD7MK From amsoft@epix.net Fri Jun 14 11:52:46 1996 Date: 11 Jun 1996 12:39:02 EDT Newsgroups: rec.radio.amateur.antenna From: hduff@hcol.humberc.on.ca (Hugh Duff) Message-ID: <8345111455901@hcol.humberc.on.ca> Subject: 6m verticals on SSB > It's perfectly true that the standard polarization for SSB work is horizonta l > and thus yagis, dipoles, square loops, etc. are best on sideband/CW/AM. > However, it's also true that polarization doesn't matter that much during ba n *************************** > openings. For example, over the past few weeks on 6m, I have worked from > _______clip______ > 73, > > Rick WB9GYT > Milwaukee, WI > EN62ax > Not entirely accurate. Signal orientation may or may not become distorted during "band openings"...it is always better to keep antenna polarity the same on both sides...degradation can be as high as 20db loss). Not to say a station working vertically will not be able to work stations horizontally polarized (as you pointed out) but there's no doubt that you would probably have had even better success on 6m SSB if you were working horizontally. One of the reasons for the convention of horizontal antenna polarization on SSB (versus vertical) is to escape a lot of man made noise which is noticeable on AM (SSB) modes. This noise is most detectable in the vertical polarity. Going horizontal could drop your noise level low enough to pull out weaker stations that may have been buried in the noise when you were vertically polarized. Of course, it's a lot more convenient to use a vertically polarized antenna on the car. It's also less of an eyesore than a horizontal omni antenna. I prefer to drive around with a 6m 1/4 wave vertical on the rear deck of the car and live with the loss and higher noise level. I've worked all over the place with my mobile on SSB. Regards... Hugh Duff VA3TO Toronto --- ţ NFX v1.3 [000] From amsoft@epix.net Fri Jun 14 11:52:47 1996 From: "Anthony R. Gold" Newsgroups: rec.radio.amateur.antenna Subject: Re: Address/Phone for Sommer??? Date: Wed, 12 Jun 96 15:06:22 GMT Message-ID: <834591982snz@microvst.demon.co.uk> References: <4pmj0p$qmk@sulawesi.lerc.nasa.gov> Reply-To: tgold@microvst.demon.co.uk In article <4pmj0p$qmk@sulawesi.lerc.nasa.gov> lawrence.wald@lerc.nasa.gov "Larry" writes: > I am looking for some info on the Sommer Co....they make beams, etc, for HF. > If someone has their address I would appreciate it. Thanks and 73. `Alf' Sommer DJ2UT Sommer-Antennas 395 Osceola Road, P.O. Box 710 Geneva FL 32732 Phone 407-349-9114 Fax 407-349-2485 He also has an email address of sommer1@ix.netcom.com, he but doesn't seem to check it too often, so a call to him or Charlotte is best. Regards, -- Tony - G3SKR / AA2PM email: tgold@panix.com tgold@microvst.demon.co.uk packet: g3skr@n0ary.#nocal.ca.usa.na From amsoft@epix.net Fri Jun 14 11:52:48 1996 From: lawrence.wald@lerc.nasa.gov (Larry) Newsgroups: rec.radio.amateur.antenna Subject: Address/Phone for Sommer??? Date: 12 Jun 1996 14:08:25 GMT Message-ID: <4pmj0p$qmk@sulawesi.lerc.nasa.gov> Hi, I am looking for some info on the Sommer Co....they make beams, etc, for HF. If someone has their address I would appreciate it. Thanks and 73. Larry, KE8GW -- =========================== Lawrence.Wald@lerc.nasa.gov NASA Lewis Research Center 21000 Brookpark Road Cleveland, Ohio 44135 Work Voice(216) 433-5219 Work Fax(216) 433-8660 Home Voice(216) 774-6848 =========================== From amsoft@epix.net Fri Jun 14 11:52:49 1996 From: jillngus@slip.net () Newsgroups: rec.radio.amateur.antenna Subject: Re: Antenna paints Date: Fri, 14 Jun 1996 00:48:14 GMT Message-ID: <4pqd9c$oc@news1.slip.net> References: Bruce Fanker wrote: >Does anyone know of any brand name NON-metallic spray paints to paint >conductive antenna parts? ex. Vertical radiator of an R7? >Thanks, >Bruce >de N0pfe Hi Bruce, I used a clear lacquer coating by Simpson on mine. I simply wiped it on with a rag. It had no effect on antenna performance. It was, and is still, a mediocre antenna with a great SWR. Mine is an R5, not an R7. From amsoft@epix.net Fri Jun 14 11:52:50 1996 Newsgroups: rec.radio.amateur.antenna From: Bruce Fanker Subject: Antenna paints (Ignor empty post) Message-ID: Date: Wed, 12 Jun 1996 18:01:17 GMT Does anyone know of any brand name NON-metallic spray paints to paint conductive antenna parts? ex. Vertical radiator of an R7? Thanks, Bruce de N0pfe From amsoft@epix.net Fri Jun 14 11:52:51 1996 From: Denis Weir Newsgroups: rec.radio.amateur.antenna Subject: Antenna's & Condos Date: Tue, 11 Jun 1996 17:38:57 -0700 Message-ID: <31BE11A1.4443@kudonet.com> Reply-To: dweir@kudonet.com San Jose, Ca. Some time ago (6 mos?) , I read in the San Jose Mercury News about a new law that limits the powers of homeowner associations regarding outdoor antenna installation. Basically the law states the association cannot flat out deny ones request to install an antenna. Can anyone point me to a document that I can arm myself with when I approach my association? BTW, After 9 years of undetected use, I just found my dual-bander all bent up and in the dumpster. The bums even yanked my coax from the outside wall, attempting to pull my gear through a very small hole. Enough is enough! From amsoft@epix.net Fri Jun 14 11:52:52 1996 From: donstone@gate.net (Don Stoner) Newsgroups: rec.radio.amateur.antenna Subject: Re: Antenna's & Condos Date: 13 Jun 1996 22:57:32 GMT Message-ID: <4pq6cs$js8@news.gate.net> References: <31BE11A1.4443@kudonet.com> Dennis... I'd suggest that you start by calling the police and reporting the destruction of federally licensed equipment. Make sure they file a report on it. Write the president of the HOA reporting what happened, stating that some vandal has destroyed federally licensed equipment and you intend to prosecute whoever is found to be responsible. I'd also suggest you visit the Antenna Restrictive Covenants home page: http://www.gate.net/~donstone/antenna.html. You may get some other ideas. Please keep me advised of what happens on this situation. Regards don stoner, W6TNS From amsoft@epix.net Fri Jun 14 11:52:53 1996 From: Robert Newsgroups: rec.radio.amateur.antenna Subject: auto tuner AT-11, jan 95 QST Date: 10 Jun 1996 23:36:12 GMT Message-ID: <4pibhc$2nd@ramp2.tir.com> hello all, can the AT-11 be modified to work the 6 meter band?? I would like the coverage to be 160-6 meters to go with my ICOM IC 706 73 rob n4yhd From amsoft@epix.net Fri Jun 14 11:52:54 1996 From: Merv Stump Newsgroups: rec.radio.amateur.antenna Subject: Re: Beam vs dipole at low height Date: 12 Jun 1996 20:28:11 GMT Message-ID: <4pn98r$fv3@mtinsc01-mgt.ops.worldnet.att.net> References: <960606213804_212147758@emout17.mail.aol.com> I ran a couple of quick models of a 20 meter dipole at 20 feet above average ground; and a 3 element close-spaced (total boom 1/4 wave length) yaggi at 20 feet above ground. The dipole shows a gain of 3 db over a dipole in freespace and the maximum radiation angle is 50 degrees.(Not much dx on that one) The yaggi shows a gain of 7 db over a dipole in freespace and the maximum radiation angle of 36 degrees.(That's still pretty high, but a big improvement) Bottom Line: Yes, the beam will be a significant improvement over the dipole even at 20 feet. Regards, Merv From amsoft@epix.net Fri Jun 14 11:52:54 1996 Newsgroups: rec.radio.amateur.antenna From: n5ejs@linknet.net (Russ) Subject: black twin-lead phone line; How many Ohms? Message-ID: <6c7cc$1622f.206@news.linknet.net> Date: Thu, 13 Jun 1996 03:24:16 GMT Reply-To: n5ejs@linknet.net Does anyone know anything about using the black 2-wire out-door telephone line as a feed line? Wonder what the feedline impedance on this stuff would be? At any rate, it looks like it would make good dipole and longwire stock. Anyone used this stuff before? de N5EJS Russ in LA. From amsoft@epix.net Fri Jun 14 11:52:56 1996 From: Siegfried Rambaum Newsgroups: rec.radio.amateur.antenna Subject: Re: black twin-lead phone line; How many Ohms? Date: Thu, 13 Jun 1996 11:20:58 -0400 Message-ID: References: <6c7cc$1622f.206@news.linknet.net> > Does anyone know anything about using the black 2-wire out-door > telephone line as a feed line? Wonder what the feedline impedance on > this stuff would be? At any rate, it looks like it would make good > dipole and longwire stock. Anyone used this stuff before? I would propose, that you read the ARRL Handbook. This stuff has an impedance, if used for the intended use. But this impedance might be of no concern to you, when you use it differently. If you cut that stuff into dipole segments, and use all the wires inside the plastic jacket, then the dipole resulting from it will have the impedance any other dipole of the same geometrical arrangement will have too. However, I am not sure, if you would have to adjust the dipole elements' lengths to adjust for operating not with a single wire dipole but a multiwire dipole. A good thing to have, when building antennas, is a noise bridge anyway. So get yourself one, ghood used ones should be around for 40...50 bucks, and less if they were homebrew... From amsoft@epix.net Fri Jun 14 11:52:56 1996 From: fj@sni.dk (Frits Jensen) Newsgroups: rec.radio.amateur.antenna Subject: Butterfly antenna from Butternut any good? Date: 10 Jun 1996 11:08:53 GMT Message-ID: <4pgvo5$1gp@news.dknet.dk> I also has limited room for big antennas. Using now simple vertical for 20M up about 20 feet. Works ok, but some directivity (F/B) is wanted to reduce QRM. The butterfly antenna has been in ads for many years, so it must be sold! Is it value for money, or will my vertical give the same DX-results?. I will like to hear from users (happy and unhappy) of this small 5-bander. Vy 73 de OZ2Q - Frits in Copenhagen - fj@sni.dk From amsoft@epix.net Fri Jun 14 11:52:57 1996 From: Jesse Touhey Newsgroups: rec.radio.amateur.antenna Subject: Re: Butterfly antenna from Butternut any good? Date: 11 Jun 1996 10:53:48 GMT Message-ID: <4pjj7s$946@crash.microserve.net> References: <4pgvo5$1gp@news.dknet.dk> Hi Frits, I have tested and tuned two Butterfly beams and in all cases this antenna leaves a lot to be desired. The traps and matching devices are mounted very flimsy. It will not stay in adjustment. The swr is not stable. Front to back ratio reverses on two bands. I recommend that you stay away from this cheaply built piece of junk! It is a mechanical monster! 73 Jesse (W6KKT) From amsoft@epix.net Fri Jun 14 11:52:58 1996 From: Jesse Touhey Newsgroups: rec.radio.amateur.antenna Subject: Re: Butterfly antenna from Butternut any good? Date: 11 Jun 1996 10:57:15 GMT Message-ID: <4pjjeb$946@crash.microserve.net> References: <4pgvo5$1gp@news.dknet.dk> Frits, a much much better alternative would be to try and find a used "Miniproducts" MiniQuad. They are no longer in business, but every once in a while I see them advertised in the used market...73 Jesse (W6KKT) From amsoft@epix.net Fri Jun 14 11:52:59 1996 From: Jim Newsgroups: rec.radio.amateur.antenna Subject: Re: Butternut HF6V Vertical: Opinions? Date: 13 Jun 1996 17:55:03 GMT Message-ID: <4ppkln$9rb@newsgate.sps.mot.com> References: <4pp9i6$qak@clarknet.clark.net> Not my very first choice for portable, but could be for somebody. The HF6V is mostly self-supporting. On mine, I always used three nylon cords for guys, located half-way up the antenna -- because we occasionally get heavy winds here. It's a "YMMV" issue but since the manufacturer suggests guying the middle of the vertical, take it for what it's worth. None of my various installations were portables -- I always installed elevated, resonant radials, the more the merrier. I had better bandwidth on the bands with more radials, but this is not JUST a factor of the radials. Anecdotal reports I've seen suggest that multiple radials work better than the counterpoise kit. The 160 meter kit will KILL bandwidth on 80, hurt 40, and generally make all tune-up more difficult, incidentally. Because of the way the resonant traps/straps/capacitors/coils attach to the vertical mast, I would not recommend an HF6V for a "quick setup portable operation" antenna. It just doesn't lend itself to easy, rapid, repeated assembly or disassembly, especially with the radial issue. But I would whole-heartedly recommend it as a DX-pedition antenna, because once set up -- a couple of hours -- it gives one of the best values for the money as far as a combination of bandwidth, short-term durability, and disposability. It's cheap enough to leave behind. And there is the UPS-shippable HF6VX (export) model, which has the longer mast sections cut into 3-foot lengths. When I think "portable" I think "easy as a walkie-talkie." So I would forego a little performance in exchange for ease of use, and get a DK3 "screwdriver" antenna, or load up a 9-foot whip with a tuner at the base. When I think "field day" I think dipole or long-wire. They're traditional. When I think "DXpedition" I think performance, reliability, redundancy, and cost is no object. An HF6V would definitely be in my DXpedition kit, along with as many yagis as I could haul, and as many dipoles as I could roll up. N6OTQ WAS 40 phone on an HF6V, incidentally. From amsoft@epix.net Fri Jun 14 11:53:00 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: DDRR antenna -reply to comments Date: 12 Jun 1996 22:33:45 -0400 Message-ID: <4pnum9$3h7@newsbf02.news.aol.com> References: <4pn69b$noa@ganesh.mc.ti.com> In article <4pn69b$noa@ganesh.mc.ti.com>, jafl@msg.ti.com (Jim Flanders) writes: >Other comments. - I cannot account for why their was more vertical >radiation when the vertical part is shortest. I also cannot account >for the reduction in vertical signal strength as I lengthened the >vertical section (until 4 ft, then it incresed again). I am also >suprised that when I placed a neon bulb along the pipe, (with 75 watts) >the bulb lit bright on only the horizontal areas (clssical DDRR config- >uration only). Are you saying the bulb lit anywhere on the horizontal area the same brightness, and never on the vertical section? Tom From amsoft@epix.net Fri Jun 14 11:53:01 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line? Date: 8 Jun 1996 22:53:54 -0400 Message-ID: <4pdec2$dp8@newsbf02.news.aol.com> References: <4pctgq$6kl@news-2.csn.net> In article , n4lq@iglou.com (Steve Ellington) writes: >This problem lies in feeder radiation. Obviously, you can't bring the >feeder away from the antenna at a right angle since it would lie on the >ground unless maybe you used two heavy coax cables to make up your >balanced feeder. With either coax or open wire line, feeder radiation is ultimately caused by uneaqual currents in the conductors. Even if the open wire line was brought away from the antenna at an angle that eliminated field coupling to the feeder, a balanced line would still radiate if the currents weren't kept exactly equal. Shielding it won't do any good, because a shield only works when it carries equal and opposite currents to whatever it is shielding. 73 Tom From amsoft@epix.net Fri Jun 14 11:53:02 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line? Date: 9 Jun 1996 13:03:59 -0400 Message-ID: <4pf05v$rdi@newsbf02.news.aol.com> References: <4pdec2$dp8@newsbf02.news.aol.com> Hi Steve, > >My idea with the coax was to keep the feeder on the ground so you could >get away from the near field of the antenna before starting with the open >wire line. I would think it would work at least a little better than >trying to run the open wire right up to the base of the antenna but maybe >not. If the shield was not resonant with the transmitted signal, would it >not act to prevent direct coupling with the center conductors? Maybe it will help a little, or maybe not at all. It might even make it worse. Anything that causes parallel currents to flow on a transmission line causes feeder radiation, and there is no way to shield the line to prevent the problem. The problem has to be eliminated by changing the "thing" causing the problem. What we really need is the line to have a very high common mode impedance at the right places, generally accomplished by properly designed and placed chokes or decoupling sleeves. 73 Tom From amsoft@epix.net Fri Jun 14 11:53:02 1996 Newsgroups: rec.radio.amateur.antenna From: n4lq@iglou.com (Steve Ellington) Subject: Re: Feeding Vertical with Balanced Line? Message-ID: References: <4p86ik$4dc@news-2.csn.net> <4pg7gv$19c@crash.microserve.net> <4pg9pc$l1@nnrp1.news.primenet.com> Date: Mon, 10 Jun 1996 17:52:57 GMT Back to the vertical question.....If one were to bring the open wire out from the base at 45 degrees, would the lines then be balanced since they are equaldistance from both the vertical and ground? -- Steve Ellington N4LQ@IGLOU.COM Louisville, Ky From amsoft@epix.net Fri Jun 14 11:53:04 1996 From: dave.lee@zetnet.co.uk (David Lee) Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line? Date: Mon, 10 Jun 1996 22:59:51 +0100 Message-ID: <4pi5vu$r6l@roch.zetnet.co.uk> In message n4lq@iglou.com (Steve Ellington) writes: > Back to the vertical question.....If one were to bring the open wire out > from the base at 45 degrees, would the lines then be balanced since they > are equaldistance from both the vertical and ground? > -- > Steve Ellington N4LQ@IGLOU.COM Louisville, Ky Hi, As I understand it a quarter wave vertical can be seen as one half of a half wave dipole working against a mirror image in the ground directly below it (rather than working against the ground surface). If this is the case an open wire feed parallel to the ground (a foot or so high) twisting to vertical at the feed point should work fine. I appreciate that with a non-resonant pole there may be some feeder radiation but what the heck, as long as it's not in the shack, radiation is what we're after. Perfect patterns are not possible on earth, who knows you may get a lobe just where you need it. Hope you have more luck this time Steve. 73 de Dave G0ROX ________________________________________________________________ | Dave Lee E-mail g0rox@ukrs.org | | Weymouth. Dorset. Packet G0ROX @GB7BNM | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ From amsoft@epix.net Fri Jun 14 11:53:05 1996 From: jackl@pinetree.microserve.com (WB3U) Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line? Date: Tue, 11 Jun 96 16:37:41 GMT Message-ID: <4pkbo1$hnl@crash.microserve.net> References: <4pj65o$5i7@crash.microserve.net> <4pjot9$end@newsbf02.news.aol.com> w8jitom@aol.com (W8JI Tom) wrote: >jackl@pinetree.microserve.com (WB3U) writes: >>I don't think the vertical is the only problem here. Even if >>the antenna was a dipole, it might be difficult to find a tuner >>that would be so well-balanced that radiation losses on 500' of >>open-wire line could be ignored. >VOA does it all the time, as I have with two wire Beverages that >use the antenna as a feedline. Tom, I don't understand what this has to do with the antenna system under discussion. First, VOA (as far as I know) isn't using non-resonant, high SWR antennas that are being switched from one band to another. Second, the beverage antenna is extremely inefficient. Aren't they used only for receiving applications? >The real problem isn't the source end, there are dozens of >simple and obvious solutions there. Yes, there are solutions. But again, I don't know of a past or present commercial tuner that can feed a non-resonant antenna on multiple bands and maintain such perfect balance that radiation losses from 500' of open wire could be ignored. If you know of a reason why this statement is wrong, please tell me. I may have a use for a longer feedline myself. 73, Jack WB3U From amsoft@epix.net Fri Jun 14 11:53:07 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line? Date: 11 Jun 1996 23:22:41 -0400 Message-ID: <4pld61$707@newsbf02.news.aol.com> References: <4pkbo1$hnl@crash.microserve.net> Hi Jack, In article <4pkbo1$hnl@crash.microserve.net>, jackl@pinetree.microserve.com (WB3U) writes: >Tom, I don't understand what this has to do with the antenna >system under discussion. First, VOA (as far as I know) isn't >using non-resonant, high SWR antennas that are being switched >from one band to another. Second, the beverage antenna is >extremely inefficient. Aren't they used only for receiving >applications? I'm sorry. These were meant to be examples of cases where the feedlines are long and don't radiate or intercept signals. My point was proper treatment of the line eliminates the problems, so the open wire line will work just fine IF ( >>The real problem isn't the source end, there are dozens of >>simple and obvious solutions there. > >Yes, there are solutions. But again, I don't know of a past >or present commercial tuner that can feed a non-resonant >antenna on multiple bands and maintain such perfect balance >that radiation losses from 500' of open wire could be ignored. >If you know of a reason why this statement is wrong, please >tell me. I may have a use for a longer feedline myself. If the line has any appreciable length compared to the wl, the radiation problem would still exist. Certainly any balun can be improved on, but I don't think things are so bad the system would be unworkable. I plan on taking some measurements under real world conditions over the next few weeks as part of a tuner project. 73 Tom From amsoft@epix.net Fri Jun 14 11:53:08 1996 From: hamop@aztec.asu.edu (CHARLES J. MICHAELS) Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line? Date: 13 Jun 1996 04:05:28 GMT Message-ID: <4po428$h8l@news.asu.edu> If this thread considers feeding a vertical against ground system then I don't seem to see anything about how the balanced line is connected to the antenna. Or I just missed it. At any rate, the balanced line should be driving the antenna through a ballanced to unbalanced balun at the antenna. I have seen some try to feed a vertical against ground by grounding one side of the balanced line at the antenna. This is a no-no. It is even worse if the transmitter end of the line is fed from a balun with a grounded center tap. Then the grounded center tap is connected to ground as is the antenna end for a completely ridiculous system. Charlie, W7XC -- From amsoft@epix.net Fri Jun 14 11:53:09 1996 From: Cecil Moore Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line? Date: 12 Jun 1996 17:54:06 -0700 Message-ID: <4pnore$3h2@nnrp1.news.primenet.com> References: <4pi5vu$r6l@roch.zetnet.co.uk> <4pj035$ljp@nnrp1.news.primenet.com> <4pj65o$5i7@crash.microserve.net> <4pjqei$1hvg@chnews.ch.intel.com> <4pkbos$hnl@crash.microserve.net> WB3U wrote: : No, not SWR. Maybe I'm oversimplifying, but it seems to me : that passing RF current through a single 100' wire will radiate : more power than passing the same current through a 1' wire. : Isn't that the same effect as common mode current traveling on : a balanced feeder? Well, in the two cases of 100/500 ft and 100/1 ft both 100 and 500 are appreciable percentages of the wavelengths involved but 1 ft is not. I'm not convinced that 15% unbalance on 500 ft will radiate appreciably more than 15% unbalance on 100 ft at the frequencies being discussed. 73, Cecil, KG7BK (W6RCA soon), OOTC From amsoft@epix.net Fri Jun 14 11:53:10 1996 From: VE4KLM Newsgroups: rec.radio.amateur.antenna Subject: help me build .001 microhenry inductor (stripline or piece of wire ?) Date: Tue, 11 Jun 1996 13:53:02 -0500 Message-ID: I am building a 6th order butterworth bandpass filter for the 2 meter band (hoping to kill the intermod problem at my location), but some of the inductors are just too small to wind using conventional air coil designs. I have seen the use of strips of metal to do this, but I do not know the calculations involved. The ARRL book I have shows lots of projects using pieces of wire or strips of metal, but they do not tell you how to calculate the inductance. Can anyone give me dimensions for a .001 microhenry strip, and also maybe some strip line formulas, so that I can create my own inductors. Thank you very much, Maiko VE4KLM --------------------- | SLM Software Inc. | | slmusr03@SLMSoft.CA | --------------------- From amsoft@epix.net Fri Jun 14 11:53:11 1996 From: VE4KLM Newsgroups: rec.radio.amateur.antenna Subject: Re: help me build .001 microhenry inductor (stripline or piece of wire ?) Date: Wed, 12 Jun 1996 09:25:21 -0500 Message-ID: References: <4pkub8$i7b@li.oro.net> <4pl1fs$kds@dfw-ixnews9.ix.netcom.com> > Very good! (mine would have been less kind). The poster gentleman > simply has not recognized the departure between mathematically > theoretical and practicable. ;) > > -=Tony=- W6ANV > Tony, if you can't answer the question, than don't turn around and slam me for it. You're talking to a Electrical Engineering person who specialized in microwave engineering, electromagnetics, etc. I simply can not seem to find a good source on constructing a simply stripline inductor. Any positive information YOU can contribute would be appreciated. Thank you VE4KMLM Maiko Langelaar Winnipeg, Manitoba --------------------- | SLM Software Inc. | | slmusr03@SLMSoft.CA | --------------------- From amsoft@epix.net Fri Jun 14 11:53:12 1996 From: Matt Strandberg Newsgroups: rec.radio.amateur.antenna Subject: Help! 6 mtr antenna problem Date: 10 Jun 1996 16:17:01 -0700 Message-ID: <4piadd$ccu@nnrp1.news.primenet.com> I recently tried to make a 6 mtr vertical antenna. I made a normal coaxial-fed dipole, with the correct length of wire. I measured it five times just to be sure. Then, I turned the antenna vertical, so that the wire was running "up and down", so that it would be a vertically polarized antenna, for FM, rather than an SSB/CW type antenna. The SWR is 4:1, and I am sure that the lengths are correct. I am using No. 16 insulated copper wire, and I can't figure out why it doesn't perform properly. Any information would be much appreciated. Thanks, matt KJ7DX mattstr@primenet.com From amsoft@epix.net Fri Jun 14 11:53:13 1996 From: "Terrence R. Redding" Newsgroups: rec.radio.amateur.antenna Subject: Re: How to connect coax to a quad antenna ??? Date: Fri, 07 Jun 1996 23:04:34 -0400 Message-ID: <31B8EDC2.2165@flinet.com> References: <4nu277$7es@news.asu.edu> <4oepiu$mrs@murphy2.servtech.com> Reply-To: pba-cct@flinet.com Robert G. Strickland wrote: > > hamop@aztec.asu.edu (CHARLES J. MICHAELS) wrote: > > >Robert G. Strickland > >rcrgs@regcon.syr.servtech.com > > said, in response to a queastion about connecting a common > >feed line to the several driven elemtns of a quad - > > >I have done some modeling of common feed quads using EZNEC, and the > >general picture is that on 10m, the pattern is semi-useless. Also, for > >a five band quad, all feeds tied together with one 2:1 balun, there > >are significant drive impedance mismatches. My conclusion is that each > >band is best driven separately, with matching adjusted for each band. > > >Robert, > > Wouldn't this modeling in EZNEC be subject to the requirements > >shown in the *Crossed dipole* model shown on page 29 of the EZNEC > >manual? > > The required minimum length of .02 wavelengths for the wire > >containing the source would seem to distort the quad from its real > >length and shape. > > I have run into this problem before trying to model some > >of the multiband verticals etx.../ > > >charlie, W7XC > >-- > Charlie... > Not being an "expert" at these things, I can only hazzard a guess. In > my 3 band, common feed model, I use the short section and tie the > three driven elements to it. From a common sense point of view, the > length of the common section seems pretty short. Also, actual I just put up a GEM quad this past weekend. I used a 1:1 balun to feed the driven element on 10/15/20 meters. It works well. I have less than 1.5:1 at the design frequency. On the air gain tests/comparisons with local hams provided a tie with a 204B mono band 4 element 20 meter yagi (he was at 55 feet, I was at 35 feet), a 2 S unit advantage for the GEM quad against a Hygain 20 meter 4 element monobander with both antennas at 35 feet. I also did a comparison against a 3 element triband beam with him at 35 feet and my antenna at 55 feet. I won out with a 2 to 4 S unit advantage. You commented earlier on the 10 meter performance of the quad with a common feed. My experience is the opposit. 10 meters is my best band with 1.1:1 SWR and obvious high gain. I work stations in Texas and Arkansas from here in West Palm Beach, Florida with S 3 to S 7 reports that on my inverted vee can't even be heard. I can't comment on the 5 band common feed. But I am very pleased with the results of the GEM quad and a 1:1 balun common feed. 73 Terry From amsoft@epix.net Fri Jun 14 11:53:14 1996 From: rcrgs@regcon.syr.servtech.com (Robert Strickland) Newsgroups: rec.radio.amateur.antenna Subject: Re: How to connect coax to a quad antenna ??? Date: Wed, 12 Jun 1996 02:12:23 -0400 (EDT) Message-ID: <4pl960$819@murphy2.servtech.com> References: <4nu277$7es@news.asu.edu> <4oepiu$mrs@murphy2.servtech.com> <31B8EDC2.2165@flinet.com> Terry... Congrads on your new Gem Quad. They make a niffty unit, and your results show it! My experience has been good with my Lighting Bolt Quad. However, 10m sort of died before I could really give it a good test up there. My "experience" has been via the EZNEC program. People have doubts about modeling quads, but no one seems to have "facts." Funny that there's so little actual measurements with the quad and quad - modeling comparisons. Lets hope this changes. STay in touch. ...Robert Robert G. Strickland rcrgs@regcon.syr.servtech.com Syracuse, New York From amsoft@epix.net Fri Jun 14 11:53:15 1996 From: gfiber@halcyon.com (Gary Fiber) Newsgroups: rec.radio.amateur.antenna Subject: Re: IC-706 Mic Date: Fri, 07 Jun 1996 03:50:42 GMT Message-ID: <4p88tt$6q3@news.halcyon.com> References: <19960606023915151.AAA219@LOCALNAME> gbishop@tc3net.COM (Gary Bishop) wrote: >This is a note concerning the audio with the IC-706 with the use of the Heil >Pro Set. >When using the proset...I noticed the radio isn't driven all that great.... >unlike the hand mike that came with the radio. >Called Heil....and they gave me some advice. Then I called Icom .... Icom >told me about the samething.... however, I was told by the service tech that >Icom would mod the radio so it would have more audio gain to make up for the >lower audio output from >the Heil headset. The mod would be done for free as a under warranty type fi x. >The down fall with this mod...is that with the use of the hand mic ...or anot her >Icom type mic.... the gain maybe a little high. You may want to Icom to get >a feel of what it is all about. >Will be going to 5W and KH8 in July .....how do I get ahold of the DX >Reflector via the internet to post the dxpedition ? >Brian KG8CO The modification appears in " Radio / Tech Modifications " published by Artsci , Inc at 818-843-4080. It is NOT an authorized ICOM, Inc nor ICOM America,, Inc modification. It is merely a field modification that gets the audio up, HOWEVER it will also greatly increase background noises picked up by the mic. Might make it hard t o use the radio with car windows open, I receive wind noise complaints after doing this modification to my 706 when driving with my truck windows open now the weather has warmed up. Gary From amsoft@epix.net Fri Jun 14 11:53:16 1996 From: dvoges@mail.global.co.za (David Voges) Newsgroups: rec.radio.amateur.antenna Subject: Info required for telescopic mast. Date: Tue, 11 Jun 1996 17:00:38 GMT Message-ID: <4pjfee$o14@dodo.global.co.za> Reply-To: [Default: blank] I have a telescopic mast (pump-up type) which has the name CLARKE engraved on it. Can someone tell me where I can find information on this mast ?. I need to service it and and also replace all the O-rings. Regards Dave From amsoft@epix.net Fri Jun 14 11:53:17 1996 From: "Ian White, G3SEK" Newsgroups: rec.radio.amateur.antenna Subject: Re: Info required for telescopic mast. Date: Tue, 11 Jun 1996 11:09:51 +0100 Distribution: world Message-ID: References: <4pjfee$o14@dodo.global.co.za> David Voges wrote: >I have a telescopic mast (pump-up type) which has the name CLARKE >engraved on it. >Can someone tell me where I can find information on this mast ?. >I need to service it and and also replace all the O-rings. > CLARK (no E) MASTS BINSTEAD ISLE OF WIGHT PO33 3PA ENGLAND Tel +44 1983 567090 Fax +44 1983 811157 They're very helpful with spares, but be sure you're sitting down when you find out the prices. 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) Professionally: IFW Technical Services Clear technical English - anywhere. From amsoft@epix.net Fri Jun 14 11:53:17 1996 From: jackl@pinetree.microserve.com (WB3U) Newsgroups: rec.radio.amateur.antenna Subject: Re: Ladder Line Quick-Disconnect Date: Mon, 10 Jun 96 04:29:40 GMT Message-ID: <4pgcmk$4d7@crash.microserve.net> References: <4pah1t$sl0@crash.microserve.net> Many thanks to everone who took time to respond to this. I've decided against using a knife-switch, simply for fear that it might not be sufficient to block the strike if the antenna takes a direct hit. The Johnson KW Matchbox I'm using has no direct connection between the ladder line and the input side of the tuner. It seems unlikely that normal static buildup could jump the air gap between the input link and the secondary, so the purpose of the quick disconnect is strictly to prevent a direct hit from charcoaling the tuner itself. Once the plug is disconnected, there will be a large physical separation of the downlead and the rig. Cecil, if I can find "Molex" connectors at Radio Shack that aren't made in China, I'll give 'em a try. I hadn't thought about using these, but they'll eliminate the minimum order charge by the sources that sell the double banana jacks. Again, thanks to all. If the connectors fry, I'll post it here. 73, Jack WB3U From amsoft@epix.net Fri Jun 14 11:53:19 1996 From: pacrimgolf@kuentos.guam.net (Jim Kehler) Newsgroups: rec.radio.amateur.antenna Subject: Re: Magic Raibeam 2 el array Date: Thu, 13 Jun 1996 05:58:07 GMT Message-ID: <4poe23$hu0@lehi.kuentos.guam.net> References: <8C24317.02CF0013DB.uuout@cencore.com> Reply-To: pacrimgolf@kuentos.guam.net armond@delphi.com wrote: >FORREST GEHRKE writes: > >>Has anyone done any serious measurements of this >>antenna? These specs are beyond belief. > >And the Easter Bunny will leave a dime under your pillow. Talk about misinformation. How are we supposed to have a decent technical discussion when people always come along and get the facts all screwed up. The Easter Bunny does *not* leave dimes under anybodys pillow. The Tooth Fairy is the one who puts the dimes under the pillow. But only in poor neighborhoods. In most places now, the Tooth Fairy puts quarters under pillows. Let's give credit where credit is due. The East Bunny lays eggs in the front yard. Colored eggs. And sometimes plastic ones with candy inside. So come on Armond, if you don't know what you're talking about, look it up in the ARRL antenna handbook before you post it next time. 73, Jim KH2D From amsoft@epix.net Fri Jun 14 11:53:19 1996 From: n7ory@primenet.com (Rob Neff (N7ORY)) Newsgroups: rec.radio.amateur.antenna Subject: Re: Magic Raibeam 2 el array Date: 13 Jun 1996 12:21:02 -0700 Message-ID: <4pppmu$o7n@nnrp1.news.primenet.com> References: <8C24317.02CF0013DB.uuout@cencore.com> <4pnld9$vrh@blixen.aquilagroup.com> Hi guys. I know Chuck (WA7RAI), Woody (WB9CQX) and the rest that were on that ad in ART. From what I hear from the people that use them, they work real good. Currently, there is some litigation going on among those who were involved with the RAI product, so I can't tell you how well the company is doing now. But no, there's no such thing as a "free" in Phoenix. Trust me. 73 Rob Neff (N7ORY) From amsoft@epix.net Fri Jun 14 11:53:21 1996 Newsgroups: rec.radio.amateur.antenna From: cluett@mv.mv.com (Jim Cluett) Subject: Re: Need Windom antenna experiences... Message-ID: Date: Fri, 14 Jun 1996 13:06:08 GMT References: <4pqpie$524@newsbf02.news.aol.com> In article <4pqpie$524@newsbf02.news.aol.com>, BillV21572 wrote: >I'm sure this thread has gone by already, but being in a constant state of >antenna experimenting, I'm now considering a Windom antenna, primarily to >gain 80 meter band exposure which I don't have with my vertical. I've got >the real estate for an off-center fed antenna like this one, but not >really >for a true 1/2 wavelength 80 mb dipole (nor the height!). A Windom would >also offer me multiband capabilities, complementing my vertical. A friend >of mine tells me his has wide bandwidths all without an antenna tuner. >Any Windom users, past and present: does off-center feeding and a >radiating vertical portion add up to reasonable performance for the >investment? Thanks in advance for any help on this. >73 de Bill ka9hln > > >Bill Vanstralen KA9HLN St. Paul, MN (612)688-2552 billv21572@aol.com Hi Bill. I'm using the Fritzel FD-4 and love it. using it with a tuner from 80 to 10. great dx on all bands. good signal reports. beautiful hardware. no complains. it's abt 45 feet high. using a yaesu ft-900AT with it. very saisfactory. I bet the carolina windom advertised in QST is good too. good luck, Jim, N1TOD From amsoft@epix.net Fri Jun 14 11:53:22 1996 From: Jake Brodsky Newsgroups: rec.radio.amateur.antenna Subject: PRB-1 (WAS: Spider Antenna) Date: Wed, 12 Jun 1996 15:17:23 -0700 Message-ID: <31BF41F3.3E1D@erols.com> References: <4pbrvn$gl8@chile.it.earthlink.net> <4pjk39$9jj@news.fwi.com> <4pjnth$acs@ecuador.it.earthlink.net> <4pkbpv$hnl@crash.microserve.net> <4pmh6f$9n9@ecuador.it.earthlink.net> Yes, unfortunately PRB-1 has its limits. What needs to be changed is the general public's hostile attitude toward antennas of any kind. They think they're getting "Beamed" with "Evil Radiation" and because of this their kids will turn out weird. Sad, but true. Solution: For those of you who do manage to get a permit to erect an antenna, DONT USE IT FOR THE FIRST FEW MONTHES! Let me relate this interesting story to you... At work, about ten years ago, we began erecting a terrestrial microwave network. We installed the dishes on top of our water tanks and then erected the buildings. There were delays due to weather. We didn't get the waveguide installed until much later. Two monthes after we erected the dish in one neighborhood, we got a call from an irate homeowner in the area. He complained bitterly that we were messsing up his TV reception. Fortunately, we hadn't even uncrated the radios yet. Our staff engineer took the call. He let this guy blow of steam. This was a really determined nitwit --he even kept a log of when we were "beaming" his TV with "interference." After about a half an hour of this, our guy said: "Gee, I really would like to help you, but somehow I don't think we're at fault here --You see we havn't even hooked up the radio yet. I'll be glad to show you the station if you're..." --That dude was so embarrassed, he hung up and we havn't heard from him since. It's easy to forget just how much you learned when you got started with this hobby. Your neighbors will never appreciate this when you request something as benign as an antenna. You must remember the first rule of antennas: Public Relations. It begins and ends there. 73, Jake Brodsky, AB3A "Beware of the massive impossible!" From amsoft@epix.net Fri Jun 14 11:53:22 1996 From: white_hae@ccsua.ctstateu.edu Newsgroups: rec.radio.amateur.antenna Subject: Q: Gain of a 6m Saturn loop? Date: 11 Jun 96 09:36:02 EST Message-ID: <1996Jun11.093602.1@ccsua.ctstateu.edu> Looking for information regarding the gain of a Saturn 6m mobile loop antenna.... Any help appreciated. Harry/N1QVE white_hae@ccsu.ctstateu.edu harry@connix.com From amsoft@epix.net Fri Jun 14 11:53:23 1996 From: Gareth Crispell Newsgroups: rec.radio.amateur.antenna Subject: Recommendations for Antenna Model Software? Date: 8 Jun 1996 16:55:44 GMT Message-ID: <4pcbag$fr5@alterdial.UU.NET> Will anyone recommend a good antenna modeling software that will give me lift < as well as Q,SWR,etc. I would need to very parameters quickly and and with ease. Running a 586 - Dos 6.2 - WFWG 3.11. Thank you people! N1MSV -- ..as for the mysteries of the Universe...they knew them not... And in the time of their visitation they shall shine, and run to and fro like sparks among the stubble. gareth e-mail stranger@ccsnet.com From amsoft@epix.net Fri Jun 14 11:53:24 1996 From: Cecil Moore Newsgroups: rec.radio.amateur.antenna Subject: Re: S-Meter values Catalogue Date: 10 Jun 1996 22:38:01 -0700 Message-ID: <4pj0np$mot@nnrp1.news.primenet.com> Bruce G. Robertson wrote: : 2. What is the right way to do this test with tools you might find : around the home/lab ? Hi Bruce, anybody working around osillyscopes will have access to 50 ohm attenuators. Signals at various 'S' meter levels can be compared with and without a 6dB attenuator, for instance. Your idea is an excellent one. Let's average the results and finally define an 'S' unit. :-) 73, Cecil, KG7BK (W6RCA soon), OOTC From amsoft@epix.net Fri Jun 14 11:53:25 1996 From: fitzgera@ykm.COM (Ron Fitzgerald) Newsgroups: rec.radio.amateur.antenna Subject: Sommer antennas Date: 8 Jun 96 23:03:31 GMT Message-ID: <01BB5554.15C70940@rons.home> Anybody out there had any experience with Sommer antennas. Their = propaganda makes the antenna out to be the best thing since sliced = whatever. Any information would be greatly appreciated. Thanks fitzgera@ykm.com From amsoft@epix.net Fri Jun 14 11:53:26 1996 From: Jim Thompson Newsgroups: rec.radio.amateur.antenna Subject: Sommer DC 280 Discone - any comments? Date: 6 Jun 1996 15:47:46 GMT Message-ID: <4p6uj2$50c@Grouper.Exis.Net> I saw the new Sommer DC 280 and DCL 280 HF-VHF discones at Dayton. Looks like a nice antenna, but does it work? Is anyone using it, yet? I would appreciate any and all comments. Thanks, Jim, W4THU jim@exis.net From amsoft@epix.net Fri Jun 14 11:53:27 1996 From: wtshaw@htcomp.net (W T Shaw) Newsgroups: rec.radio.amateur.antenna Subject: Re: Spider antenna Date: 9 Jun 1996 05:41:36 GMT Message-ID: References: <4pbrvn$gl8@chile.it.earthlink.net> > > Roger J. Buffington; AB6WR (rogerjb@earthlink.net) wrote: > : I recently moved into a community which, alas, has restrictive CC&Rs which > : do not permit antennas. However, I have a nice attic two stories up, > : towering over the ocean, an obvious site for my antenna array. Has anyone > : out there used those "Spider" multi-band dipoles advertised in QST? These > : seem like they would be ideal covert attic antennas. > > : Roger J. Buffington > : AB6WR > : USC Law School Class of '97 There are lots of possibilities. I've used good attic antennas in the past. At present, I have a metal roof so that is not practical. It all depends on the room you have in your attic. How about giving some physical dimensions including vertical space and which way the roof slants, if it does. Bill, K5PCW /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ wtshaw@htcomp.net Mac Crypto Programs You should at least know how to use ROT13. "Fhpprff vf n Wbhearl, Abg n Qrfgvangvba." http://www.htcomp.net/wts/wtcrypto.htm \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/ From amsoft@epix.net Fri Jun 14 11:53:28 1996 From: bduxbury@zetnet.co.uk (Sir Barry Duxbury) Newsgroups: rec.radio.amateur.antenna Subject: Re: Spider antenna Date: Sun, 9 Jun 1996 07:39:37 +0100 Message-ID: <4pdsop$co2@roch.zetnet.co.uk> References: <4pbrvn$gl8@chile.it.earthlink.net> In message n4lq@iglou.com (Steve Ellington) writes: > Roger. I would stay away from vertical antennas in an attic. You would > need some form of ground plane and it just isn't there. > Roger J. Buffington; AB6WR (rogerjb@earthlink.net) wrote: > : I recently moved into a community which, alas, has restrictive CC&Rs which > : do not permit antennas. However, I have a nice attic two stories up, > : towering over the ocean, an obvious site for my antenna array. Has anyone > : out there used those "Spider" multi-band dipoles advertised in QST? These > : seem like they would be ideal covert attic antennas. > : Roger J. Buffington > : AB6WR > : USC Law School Class of '97 > : rogerjb@earthlink.net > : "I want to die peacefully, in my sleep, like my grandfather. > : Not screaming, and in terror, like his passengers." Roger, I think your question was misunderstood! The idea of using two whips in dipole configuration is very sound, indeed if you wish to demonstrate the performance you can try two one band whips which are very reasonably priced. It works well for me when operating portable.. and much better than trying to use a vertical whip against a poor ground. Best 73 ...Barry -- Barry Duxbury bduxbury@zetnet.co.uk 100031.2223@compuserve G4GAH Oxford UK From amsoft@epix.net Fri Jun 14 11:53:29 1996 Newsgroups: rec.radio.amateur.antenna From: Bruce Fanker Subject: Spray paint for antennas Message-ID: To: Antenna,paints Date: Wed, 12 Jun 1996 17:50:42 GMT Does anyone know of any brand name NON-metallic spray paints to paint conductive antenna parts? ex. Vertical radiator of an R7? Thanks, Bruce de N0pfe From amsoft@epix.net Fri Jun 14 11:53:30 1996 From: gsparks@ix.netcom.com(Glenn Sparks) Newsgroups: rec.radio.amateur.antenna Subject: Stainless Steel wire as Antenna? Date: 10 Jun 1996 19:35:44 GMT Message-ID: <4phteg$9c8@dfw-ixnews10.ix.netcom.com> I have a beach house near Galveston, Texas, and the environment destroys my antenna system every year. I have a 80 / 40 meter fan dipole up about 45 feet. I have been using galvanized wire for the guys, and copperweld for the antenna and dacron rope. First the guy wire will rust into, about 8 months, then the copperweld will go, the Dacron seems to hold up well though. I bought Stainless steel guy wire and was told that it would work fine for the antenna as well. Does anyone have any experience with this, it is multistrand stainless steel wire, about 7 strand, looks about 14 gauge total size. Does anyone have anyone have any experience with this wire as an antenna? I have some stainless steel hardware at the beach house already, and while it lasts, it does get an ugly coating. Will this coating (probably from the salt) effect radiation? and lastly how can I connect my feedline to Stainless Steel? Any suggestions will be most welcome. Thanks, Glenn Sparks KI5GY From amsoft@epix.net Fri Jun 14 11:53:31 1996 From: frank.dinger@zetnet.co.uk (Frank Dinger) Newsgroups: rec.radio.amateur.antenna Subject: Re: Stainless Steel wire as Antenna? Date: Tue, 11 Jun 1996 20:43:23 +0100 Message-ID: <4pnca7$6t8@roch.zetnet.co.uk> References: <4phteg$9c8@dfw-ixnews10.ix.netcom.com> <4piem7$rh4@hpcvsnz.cv.hp.com> In message <4piem7$rh4@hpcvsnz.cv.hp.com> tomb@lsid.hp.com (Tom Bruhns) writes: > Glenn Sparks (gsparks@ix.netcom.com) wrote: > : I have a beach house near Galveston, Texas, and the environment > : destroys my antenna system every year. I have a 80 / 40 meter fan > : dipole up about 45 feet. I have been using galvanized wire for the > : guys, and copperweld for the antenna and dacron rope. First the guy > : wire will rust into, about 8 months, then the copperweld will go, the > : Dacron seems to hold up well though. > : I bought Stainless steel guy wire and was told that it would work fine > : for the antenna as well. Does anyone have any experience with this, it > I used stainless aircraft control cable for an antenna when I was at > Adak, AK, "Birthplace of the Winds." It held up in the weather fine, > but I always felt it was a darned poor performer for an antenna. At > this point, I couldn't tell you if it was magnetic or not. (See Roy > Lewallen's posting.) > I'm wondering what makes the copperweld go so quickly. It seems like > that's too fast even under moderate salt spray conditions, if it's > properly installed. You do have to be careful not to nick it. What's used > aboard ships for antennas?? Can you paint the wire with acrylic paint, > perhaps by a dipping operation? > -- > Cheers, > Tom > tomb@lsid.hp.com ========== response GM0CSZ / KN6WH Suggest to use black poly-ethylene or poly-propylene sheathed copper or steel antenna wire ,in a saliferous environment. Exposed wire ends can be covered with 2 component epoxy (glue) or wax oil. Frank Dinger , Inver by Tain , Ross-shire IV20 1RX - Scotland e-mail : gm0csz.kn6wh@ukrs.org Packet : GM0CSZ @ GB7NOS.#76.GBR.EU From amsoft@epix.net Fri Jun 14 11:53:32 1996 From: burro Newsgroups: rec.radio.amateur.antenna Subject: TA-33 Trap Help Needed Date: Mon, 10 Jun 1996 13:32:00 +0300 Message-ID: <31BBF9A0.179C@beaches.net> Have TA-33 triband. Problem: Have all the traps except there were three reflector traps which means the director now has one director trap and one reflector trap. The driven element is OK. The reflector is OK. What problems might this create and is there a way to make the trap correct for the director. Any help offered would be greatly appreciated. Barry WB6LDL From amsoft@epix.net Fri Jun 14 11:53:32 1996 From: jrmoore@ilnk.com (John R. Moore) Newsgroups: rec.radio.amateur.antenna Subject: Test Date: Sun, 09 Jun 1996 22:59:41 GMT Message-ID: <31bb1fb1.0@news.ilnk.com> This is only a test post From amsoft@epix.net Fri Jun 14 11:53:33 1996 From: Bob Smith Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.digital.misc,rec.radio.amateur.equipment,rec.radio.amateur.space,rec.radio.swap Subject: Trade DSP-93 for DSP2232 or 1232 Date: 8 Jun 1996 02:17:04 GMT Message-ID: <01bb54e0.94e406c0$25a447cc@desktop> Hate to do it but I just have no time to tweak my DSP93 as I need to get it going for sat work. SO I wish to trade it for a DSp2232 or 1232. It is built and works perfectly. Also includes the PACCOMM TNC board installed. Includes all docs and software. Thanks for the bandwidth Get me at bsmith@msn.com. 73. ------------------------------------------------------------------- Bob Smith N3FTU Suwanee, GA mailto: bsmith@msn.com http://www.wp.com/~bsmith ARRL, TAPR From amsoft@epix.net Fri Jun 14 11:53:34 1996 From: paulegan@interlog.com (Paul Egan) Newsgroups: rec.radio.amateur.antenna Subject: Trap dipole with 450 ohm slotted line? Date: Tue, 11 Jun 96 16:34:43 GMT Message-ID: <4pk787$g2m@news.interlog.com> Can 450 ohm slotted line be used as the feedline of a trap dipole? I have a 130' inverted V with this slotted line currently. I get fair to good reports on 40 and 80, fair to poor on 20 and 15 and no tune on 10. I was thinking of replacing it with a 40/80 trap dipole. Can I reuse my slotted line or am I going out to the store for new coax? Thanks Paul Egan VE3GFY From amsoft@epix.net Fri Jun 14 11:53:35 1996 From: jackl@pinetree.microserve.com (WB3U) Newsgroups: rec.radio.amateur.antenna Subject: Re: Trap dipole with 450 ohm slotted line? Date: Wed, 12 Jun 96 21:23:46 GMT Message-ID: <4pncho$557@crash.microserve.net> References: <4pk787$g2m@news.interlog.com> paulegan@interlog.com (Paul Egan) wrote: >Can 450 ohm slotted line be used as the feedline of a trap >dipole? I have a 130' inverted V with this slotted line currently. >I get fair to good reports on 40 and 80, fair to poor on 20 and 15 >and no tune on 10. I was thinking of replacing it with a 40/80 >trap dipole. Can I reuse my slotted line or am I going out to the >store for new coax? Paul, is the dipole resonant on all the bands you're using it on? If so, ladder line can present more headaches than benefits. In fact, you may be losing power in some parts of the system due to the mismatch between the line and the antenna. That could account for your poor results on 20, 15 and 10 meters. IMO, you would be better off to install a current balun at the center of the dipole and feed it with the appropriate type of coax. 73, Jack WB3U From amsoft@epix.net Fri Jun 14 11:53:36 1996 From: rwa@cs.athabascau.ca (Ross Alexander) Newsgroups: rec.radio.amateur.antenna Subject: Re: two nearby towers (fwd) Date: 12 Jun 1996 16:19:10 GMT Message-ID: <4pmqlu$r37@aurora.cs.athabascau.ca> References: Siegfried Rambaum writes: >What will happen, when you both operate? The signal from one tower will >overload the front end of the other guy. THERE SIMPLY IS NO WAY FOR YOU >BOTH TO OPERATE AT THE SAME TIME !!!!!! repeat, there simmply is no way >for you to operate at the same time. Twenty meters distance between both >towers ... 66 feet .... Not so. I've operated lots of contests at a multi-multi site where the spacing between antennas wasn't much greater than that, and we were running max legal power on two or three transmitters simultaneously; proper external bandpass filters and very very careful attention to bonding handles the problem quite nicely. regards, Ross ve6pdq -- Ross Alexander, ve6pdq -- (403) 675 6311 -- rwa@cs.athabascau.ca From amsoft@epix.net Fri Jun 14 11:53:37 1996 From: Jesse Touhey Newsgroups: rec.radio.amateur.antenna Subject: Re: Vert gain vs Dipole gain 80 meters Date: 10 Jun 1996 01:54:55 GMT Message-ID: <4pfv9g$skk@crash.microserve.net> References: <4p78fa$ie5@nnrp1.news.primenet.com> <4p8rsq$pli@newsbf02.news.aol.com> Tom: Here in California working very long path on 80 meters 5000 to 12000 miles my horiz dipole up 100' fed with 600 ohm feeders without exception has never been beaten by a single element well designed vertical system. I'm very surprised by you experience. The 100' high dipole (both ends) has almost the same performance as a 4square in its best direction. The only systems that will do better is the very high full size yagi's etc. Perhaps your path is shorter? My dipole exhibits around 3.7 dbi at 20 degrees. Your single element vert unless it is over salt water wont do that. Respectfully,....Jesse (W6KKT) From amsoft@epix.net Fri Jun 14 11:53:38 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Vert gain vs Dipole gain 80 meters Date: 10 Jun 1996 09:41:17 -0400 Message-ID: <4ph8lt$jab@newsbf02.news.aol.com> References: <4pfv9g$skk@crash.microserve.net> In article <4pfv9g$skk@crash.microserve.net>, Jesse Touhey writes: > >Tom: Here in California working very long path on 80 meters 5000 to 12000 >miles my horiz dipole up 100' fed with 600 ohm feeders without exception >has never been beaten by a single element well designed vertical system. >I'm very surprised by you experience. The 100' high dipole (both ends) >has almost the same performance as a 4square in its best direction. The >only systems that will do better is the very high full size yagi's etc. >Perhaps your path is shorter? My dipole exhibits around 3.7 dbi at 20 >degrees. Your single element vert unless it is over salt water wont do >that. Respectfully,....Jesse (W6KKT) Hi Jesse, I don't know the real reason, I'm sure the good ground system helps. My verticals have full size radial systems, and the dipole is up over the radial system of the 160 vertical, absolutely broadside on Europe. Looking at distance vs wave angle charts, it shouldn't be a wave angle problem from being close to Europe. Besides, I get the same results into ZL...and thats also broadside to the dipole. I know NEC based programs say the dipole should be slightly better, but it just doesn't work out that way in practice. On 160 in Sylvania Ohio I had a 1/4 wl vertical and a dipole at 350 ft. The dipole easily beat the vertical. But when the same dipole was only at 250 ft the difference wasn't so obvious, the antennas would often be tied. Those were A-B tests and the antennas were about a mile or so apart on flat black wet sandy loam soil. 73 Tom From amsoft@epix.net Fri Jun 14 11:53:38 1996 From: Bill Levey Newsgroups: rec.radio.amateur.antenna Subject: Web Vendor Directory Date: Tue, 11 Jun 1996 09:54:23 -0500 Message-ID: <31BD889F.5AFE@bro.net> A comprehensive directory of Amateur Radio businesses on the web is available at: http://www.scott.net/~wa4fat/vendor.html From amsoft@epix.net Fri Jun 14 11:53:39 1996 From: phertler@ (Peter Hertler) Newsgroups: rec.radio.amateur.antenna Subject: Re: What's the best height for an R-7 Date: 10 Jun 1996 13:26:19 GMT Message-ID: <4ph7pr$1ki8@ausnews.austin.ibm.com> References: <4ovt9k$os0@oskgw.osk.sony.co.jp> Reply-To: phertler@ (Peter Hertler) In <4ovt9k$os0@oskgw.osk.sony.co.jp>, Peter Shintani writes: >Hi: > I have an R-7 mounted on the side of my house. The base of the antenna is a djacent >to the eaves trough. The eaves trough is about 6m above the ground. It seems to work, >but QRN trash is about s-9 anytime of the day. 40 m performance seems ok, but >20 and 15 m is too quiet, perhaps the antenna is not working well. > >I am considering remounting the antenna on to the peak of the roof on top of a 4m >mast. Would the additional 4m of height be significant ? >I know that higher is better for most antenna's but in the case of a vertical , and >specifically the halfwave R-7 vertical does the low angle radiation worsen ? >For example do strange lobes appear when the antenna is raised to far above the ground ? > >Peter > > The manual specifies 8 feet off the ground is best. Keep us posted. Regards peter@vnet.ibm.com From amsoft@epix.net Fri Jun 14 11:53:40 1996 From: K5ESW@nando.net (Paul Ferguson) Newsgroups: rec.radio.amateur.antenna Subject: Re: What's the best height for an R-7 Date: Wed, 12 Jun 1996 11:07:40 GMT Message-ID: <4pm8gr$nkm@castle.nando.net> References: <4ovt9k$os0@oskgw.osk.sony.co.jp> <4ph7pr$1ki8@ausnews.austin.ibm.com> >> >>I am considering remounting the antenna on to the peak of the roof on top o f a 4m >>mast. Would the additional 4m of height be significant ? >>I know that higher is better for most antenna's but in the case of a vertica l, and >>specifically the halfwave R-7 vertical does the low angle radiation worsen ? >>For example do strange lobes appear when the antenna is raised to far above the ground ? >> >>Peter >> >> >The manual specifies 8 feet off the ground is best. > My R-7 Manual says the dimensions recommended are based on the R7 approx. 8 feet above ground and 25 feet from surrounding objects. It does not say 8 feet is the optimum height. I assume they are saying the dimensions may change as you tune the antenna for min SWR. I do not have the answer as to optimum height. Maybe someone has modeled the antenna? 73, Paul Ferguson K5ESW@nando.net From amsoft@epix.net Fri Jun 14 11:53:41 1996 From: Cecil Moore Newsgroups: rec.radio.amateur.antenna Subject: Re: Wire antennas in salty environment Date: 12 Jun 1996 21:23:01 -0700 Message-ID: <4po535$oum@nnrp1.news.primenet.com> References: <4pn1bk$fk@doc.zippo.com> S.Y.Stroobandt@e-eng.hull.ac.uk wrote: : I've been following the postings on stainless steel antennas and I wonder : if somebody can conclude on which type of wire is best for antennas in : a salty environment. I believe that good insulation and a good paint would do the job quite nicely. These two things have virtually eliminated a static electricity problem I had. Course, Phoenix is not all that salty or humid. 73, Cecil, KG7BK (W6RCA soon), OOTC From amsoft@epix.net Wed Jun 19 21:10:25 1996 From: atkes@imap1.asu.edu Newsgroups: rec.radio.amateur.antenna Subject: 50 ohm adapters Date: 16 Jun 1996 02:17:46 GMT Message-ID: <4pvqsa$mm@news.asu.edu> I apologize since this is not exactly about antennas. It is about feedline connectors, so this seemed to me to be a reasonable group. I have an HP-817A swept slotted line system in nice condition that I would like to use at 2.3 to 10 GHz. This is your basic hamfest $50 or less item since very few hams want these, and commercial places have long ago moved to network analyzers. The output connector is an Amphenol APC-7. I would like to find an adapter from this connector to some more common (at least among hams) type such as an SMA, N, GR-874 etc. with reasonable performance, and pay less than I did for the whole rest of the system. :-) Does anyone have, or know of a surplus place that might have, these at surplus/hamfest prices? The HP part number for an APC-7 to N female adapter is 11524A, and from APC-7 to N male is 11525A if that helps. I have a catalog from Pasternak Enterprises. Their price for a new adapter, from a regular 7mm connector (I assume the APC-7 stands for Amphenol Precision Connector 7mm) to an SMA female, is $170.00 in single quantity. I'm looking for something considerably cheaper. :-() 73 Kevin w9cf@ptolemy.la.asu.edu From amsoft@epix.net Wed Jun 19 21:10:26 1996 From: ermira@pl.jaring.my Newsgroups: rec.radio.amateur.antenna Subject: antenna Date: 18 Jun 1996 22:59:02 GMT Message-ID: <4q7cbm$hm2@jaring.my> pls include me in your mailing list From amsoft@epix.net Wed Jun 19 21:10:26 1996 From: John O'Brien Newsgroups: rec.radio.amateur.antenna Subject: antenna design software Date: Mon, 17 Jun 1996 19:23:23 -0400 Message-ID: <31C5E8EB.69A@ici.net> greatings! i am a ham who likes to experiment with antenna designs, trial and error and such, does anyone out there know of any good windows based shareware, freeware, demo, whatever, antenna design programs? should allow cad type work, built in formulas, etc. for testing the design before picking up a soldering iron and coax......thanks in advance! 73's N1NJI From amsoft@epix.net Wed Jun 19 21:10:27 1996 Newsgroups: rec.radio.amateur.antenna From: Bruce Fanker Subject: Antenna paints Message-ID: To: Neswgroup:rec.radio.amateur.antenna Date: Wed, 12 Jun 1996 17:55:07 GMT Does anyone know of any brand name NON-metallic spray paints to paint conductive antenna parts? ex. Vertical radiator of an R7? Thanks, Bruce de N0pfe From amsoft@epix.net Wed Jun 19 21:10:28 1996 Newsgroups: rec.radio.amateur.antenna From: webbte Subject: Re: Antenna paints Message-ID: Reply-To: ted.webb@columbiasc.ncr.com (webbte) References: Date: Thu, 13 Jun 1996 17:15:26 GMT Bruce - I asked a similar question about 3 months ago and was generally told just to make sure is was non-metallic. The concensus was a flat latex, green or brown, was the best for concealment purposes. I also have an R-7 that I need to paint. Hope this helps. ted / ac4cs >==========Bruce Fanker, 6/12/96========== > >Does anyone know of any brand name NON-metallic spray paints to paint >conductive antenna parts? ex. Vertical radiator of an R7? > >Thanks, > >Bruce >de N0pfe > > From amsoft@epix.net Wed Jun 19 21:10:29 1996 From: jillngus@slip.net () Newsgroups: rec.radio.amateur.antenna Subject: Re: Antenna's & Condos Date: Fri, 14 Jun 1996 00:41:17 GMT Message-ID: <4pqcs8$oc@news1.slip.net> References: <31BE11A1.4443@kudonet.com> Denis Weir wrote: >San Jose, Ca. >Some time ago (6 mos?) , I read in the San Jose Mercury News about a new >law that limits the powers of homeowner associations regarding >outdoor antenna installation. Basically the law states the association >cannot flat out deny ones request to install an antenna. >Can anyone point me to a document that I can arm myself with when I >approach my association? >BTW, After 9 years of undetected use, I just found my dual-bander all >bent up and in the dumpster. The bums even yanked my coax from the >outside wall, attempting to pull my gear through a very small hole. >Enough is enough! Hi Denis, I think what you are probably referring to is the new DSS law. As I recall, it forbids CC&R's from stopping the installation of satellite dishes up to 36 inches, and TV antennas for local coverage. The law was pushed through by Pacbell (I wonder what they have up their sleeve??). It has no effect on ham antennas, unfortunately, unless there is a loophole for amateur satellites. I, fortunately, live in a condo that has no antenna restriction, so I didn't follow the news all that closely. From amsoft@epix.net Wed Jun 19 21:10:30 1996 From: kk5hy@accesscom.net (Jake Hellbach) Newsgroups: rec.radio.amateur.antenna Subject: Anyone use the MFJ-1798 ??? Date: Sun, 16 Jun 1996 13:33:37 GMT Message-ID: <4q12j0$2ho@ux.accesscom.net> Hello to all, I was wondering if any has used or has any Feedback on the MFJ-1798 10 band antenna. How does it measure up to other antenna's of the same type? Thanks, Jake KK5HY ++++++++++++++++++++++++++++++++++++++++++++++++++++++ email via: kk5hy@accesscom.net Check out the Westside A.R.C. Web page at: http://www.accesscom.net/~kk5hy Now updated with Boatanchor links! ++++++++++++++++++++++++++++++++++++++++++++++++++++++ From amsoft@epix.net Wed Jun 19 21:10:31 1996 From: white_hae@ccsua.ctstateu.edu Newsgroups: rec.radio.amateur.antenna Subject: Re: Beam vs dipole at low height Date: 14 Jun 96 08:08:43 EST Message-ID: <1996Jun14.080843.1@ccsua.ctstateu.edu> I'm not an antenna expert, but I play one on TV.... From a practical, applied perspective, we ran a TH3JR tribander mounted on a Rohn25 top section during the '94-'95 winter (waiting for the thaw for the tower installation). The beam was up about 15'. We also ran a G5RV up 40'. For DX, the beam outperformed the G5RV in all regards; I cannot give an opinion on close-in performance as I can't recall working the local-to-midrangers... BTW, for a temp mount, we took a Rohn baseplate and welded it to one end of a 36"x24" piece of 3/8" plate. Stacking cinder blocks around it allowed the assembly to withstand that record-setting winter. 73 Harry/N1QVE From amsoft@epix.net Wed Jun 19 21:10:33 1996 From: andy@pythagoras.org (The Tie-Dyed Side of the Force) Newsgroups: rec.radio.amateur.antenna Subject: Re: Beam vs dipole at low height Date: Sat, 15 Jun 96 06:52:21 GMT Message-ID: <4ptmhq$gc7@masters0.Internex.NET> References: <4p579c$eki@mark.ucdavis.edu> <4p9qoc$16uo@chnews.ch.intel.com> <4pbgfi$t80@nadine.teleport.com> In article , commo@k1log.ultranet.com (Norm Commo) wrote: >I will second Roy's comments here. I recently went through a design of a >three element 40M beam for Field Day. It needed to be supported by only two >poles so it's elements droop. I kept the angle to 38 degrees based on how far >away I wanted the anchor lines to be.... >At Field Day the antenna will be mounted at 40 feet on from two masts and a >rope boom. The wire size is #12 wire. I've been wondering about wire beams, particularly because I don't have a tower, but do have a large number of really tall redwoods. Has anybody done a multiple-tree-supported wire beam? Has anyone tried making one that was at least partly aimable (using ropes & pulleys)? From amsoft@epix.net Wed Jun 19 21:10:33 1996 From: Jake Brodsky Newsgroups: rec.radio.amateur.antenna Subject: Re: black twin-lead phone line; How many Ohms? Date: Thu, 13 Jun 1996 08:26:17 -0700 Message-ID: <31C03319.7D95@erols.com> References: <6c7cc$1622f.206@news.linknet.net> I can't be sure which wire you're writing about. But I do have a few generalizations regarding telephone wiring. This comes from a BELCORE technical publication: The impedance varies with frequency. I think it was intended for either 600 or 900 ohms at audio but then drops to about 100 ohms around 1 MHz. It was intended to look like the twisted pair stuff they use. Like Zip cord --this stuff was not intended for RF. 73, Jake Brodsky, AB3A "Beware of the massive impossible!" From amsoft@epix.net Wed Jun 19 21:10:34 1996 From: kk5hy@accesscom.net (Jake Hellbach) Newsgroups: rec.radio.amateur.antenna Subject: Re: Butterfly antenna from Butternut any good? Date: Sun, 16 Jun 1996 13:46:38 GMT Message-ID: <4q13bc$2rj@ux.accesscom.net> References: <4pgvo5$1gp@news.dknet.dk> Hi Frits, Well I am in the same boat as to using a small beam, My butterfly beam works a little better than a dipole 20 meters, but good f/b. On 15 to 10 meters it works great, sometimes 2 to 3 S units more than my dipole. 12 meters works O.K. Don't even try 17 meters you can't hear anything. Hope this helps, Jake KK5HY fj@sni.dk (Frits Jensen) wrote: >I also has limited room for big antennas. Using now simple vertical for 20M u p >about 20 feet. Works ok, but some directivity (F/B) is wanted to reduce QRM. >The butterfly antenna has been in ads for many years, so it must be >sold! Is it value for money, or will my vertical give the same DX-results?. >I will like to hear from users (happy and unhappy) of this small 5-bander. >Vy 73 de OZ2Q - Frits in Copenhagen - fj@sni.dk ++++++++++++++++++++++++++++++++++++++++++++++++++++++ email via: kk5hy@accesscom.net Check out the Westside A.R.C. Web page at: http://www.accesscom.net/~kk5hy Now updated with Boatanchor links! ++++++++++++++++++++++++++++++++++++++++++++++++++++++ From amsoft@epix.net Wed Jun 19 21:10:35 1996 From: pacrimgolf@kuentos.guam.net (Jim Kehler) Newsgroups: rec.radio.amateur.antenna Subject: Re: Butternut HF6V Vertical: Opinions? Date: Fri, 14 Jun 1996 11:31:51 GMT Message-ID: <4prm04$5of@lehi.kuentos.guam.net> References: <4pp9i6$qak@clarknet.clark.net> Reply-To: pacrimgolf@kuentos.guam.net cteclaw@clark.net (Charles Teclaw) wrote: >Would appreciate any comments on the HF6V, especially concerning whether >it is really self-supporting, structural soundness, thoughts on radials >vs. counterpoise system, and whether it might lend itself to quick setup >portable operation from a pop-up camping trailer. I know some of these >points have been discussed on the group, but deja news couldn't locate >them. >Thanks in advance. 73 de NT3G (Chuck) Chuck, I've used a HF6V for some time, and also an HF2V (?) the 40/80 meter version. I guy mine with light nylon line. If it was ground mounted temporarily, you could probably live without the guys. I have experimented with various radial systems, and a couple of tuned radials on 20/40 seemed to do the job, but I really can't say I notice a lot of difference without them. The 2V was mounted on top of an 8 story building with no radials at all and some U.S. stations had trouble believing I wasn't using a beam (of course, we are surrounded by salt water). As for 'quick setup' I think you could have it playing in 10 or 15 minutes if you leave it partially assembled when you transport it. The antenna has no traps, like some of the newer HF verticals, and although it's been a few years since I bought one, I think they were about half the price of some of the trapped verticals. All in all I think it's an excellent antenna. Only problem I've ever had is that I melted one of the insulators that holds the 15 meter wire away from the mast and cooked the wire itself, but that was very easy to fix. 73, Jim KH2D From amsoft@epix.net Wed Jun 19 21:10:36 1996 From: Russell.Blair@mci.com (Russell Blair) Newsgroups: rec.radio.amateur.antenna Subject: Cable TV Hardline connectors. Date: Wed, 12 Jun 1996 12:30:24 GMT Message-ID: <4pmd7o$ite@news.internetmci.com> I cant seem to find were in the Dallas area were to buy connectors for Cable TV hardline. If anyone has a phone number please e-mail back. Russell From amsoft@epix.net Wed Jun 19 21:10:37 1996 From: Hadley@.arva.com, N7REN@.arva.com Newsgroups: rec.radio.amateur.antenna Subject: Dual band J-Pole Date: Mon, 17 Jun 96 09:50:41 PDT Message-ID: Looking for dimensions for 1/2" Cu. 146/446 J-Pole. Thanks for the help. Pls e-mail to hadley@arva.com Hadley, N7REN From amsoft@epix.net Wed Jun 19 21:10:38 1996 From: sco@sco-inc.com Newsgroups: rec.radio.amateur.antenna Subject: Re: Eggbeater Antenna Date: Sun, 16 Jun 1996 05:51:06 GMT Message-ID: <4q07f7$18au@mule1.mindspring.com> References: <00000685000032AA@nashville.com> Reply-To: sco@sco-inc.com mark.endicott@nashville.com (Mark Endicott) wrote: >Somewhere in a former life I recall a design for the "eggbeater" antenna. >It was used for space communications as it had a high angle pattern. >Anybody have any of the design details. 73....Mark WB0NOO > mark.endciott@nashville.com Has anyone used the 2m and 440 eggbeaters antennas to operate any satelittes? If so how did you do it, which satelittes, etc? From amsoft@epix.net Wed Jun 19 21:10:39 1996 From: luis velis Newsgroups: rec.radio.amateur.antenna Subject: Eggbeater Any comments..? Date: 19 Jun 1996 15:12:47 GMT Message-ID: <4q95df$ej0@news2.cais.com> Hello all I am interesting to know more about the eggbeaters antennas... Are they any good..? Can someone send me the plans...? best 73's de Luis/n3tuk From amsoft@epix.net Wed Jun 19 21:10:40 1996 From: Doug Person Newsgroups: rec.radio.amateur.antenna Subject: Re: Experiences with AEA ISO-Loop? Date: Sat, 15 Jun 1996 08:42:14 -0700 Message-ID: <31C2D9D6.184D@ibm.net> References: <4prr1i$2l4@nnrp1.news.primenet.com> I have one and have used it off and on for a few years. They work ok, but have some operational drawbacks. Tuning it can be very critical and time-consuming. It is often very difficult to find the point were it resonates for the frequency you want. Once tuned, the bandwidth is very narrow. AEA does offer an automatic tuner with which I have no experience. MFJ also sells a loop antenna which includes an automatic tuner. I Would be interested in a comparison between the AEA and the MFJ, or if anyone has some words about the MFJ at all. 73, Doug - KI6BQ From amsoft@epix.net Wed Jun 19 21:10:41 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line? Date: 13 Jun 1996 11:13:50 -0400 Message-ID: <4ppb7e$go1@newsbf02.news.aol.com> References: <4po428$h8l@news.asu.edu> In article <4po428$h8l@news.asu.edu>, hamop@aztec.asu.edu (CHARLES J. MICHAELS) writes: > > If this thread considers feeding a vertical against ground >system then I don't seem to see anything about how the balanced >line is connected to the antenna. Or I just missed it. Hi Charlie, I did say something similar several times. But your reply was more to thepoint. In one case I said: Date: 9 Jun 1996 13:03:59 -0400 "Anything that causes parallel currents to flow on a transmission line causes feeder radiation, and there is no way to shield the line to prevent the problem. The problem has to be eliminated by changing the "thing" causing the problem. What we really need is the line to have a very high common mode impedance at the right places, generally accomplished by properly designed and placed chokes or decoupling sleeves." My point was an isolating device (balun) is necessary, not a simple untuned shield. 73 Tom From amsoft@epix.net Wed Jun 19 21:10:42 1996 From: jvaldes Newsgroups: rec.radio.amateur.antenna Subject: Re: help me build .001 microhenry inductor (stripline or piece of wire ?) Date: Fri, 14 Jun 1996 12:30:20 -0400 Message-ID: <31C1939C.5A94@whoi.edu> References: VE4KLM wrote: > > I am building a 6th order butterworth bandpass filter for the 2 meter > band (hoping to kill the intermod problem at my location), but some > of the inductors are just too small to wind using conventional air > coil designs. I have seen the use of strips of metal to do this, but > I do not know the calculations involved. The ARRL book I have shows > lots of projects using pieces of wire or strips of metal, but they do > not tell you how to calculate the inductance. > > Can anyone give me dimensions for a .001 microhenry strip, and also maybe > some strip line formulas, so that I can create my own inductors. > > Thank you very much, > > Maiko > VE4KLM > > --------------------- > | SLM Software Inc. | > | slmusr03@SLMSoft.CA | > ---------------------How about a small resonant cavity? I've made several o ut of 2 inch pipe and also square cavities from pc board stock. Mechanically their easy to construct and not difficult to tune. You can even add a notch to the bandpass characteristic if the offending frequency isn't too far away. Generally speaking, to eliminate the intermod it's only necessary to remove one of the offending frequencies to eliminate the mixing. From amsoft@epix.net Wed Jun 19 21:10:43 1996 From: "Michael G. Katzmann" Newsgroups: rec.radio.amateur.antenna Subject: Re: help me build .001 microhenry inductor (stripline or piece of wire ?) Date: Sat, 15 Jun 1996 20:43:22 -0400 Message-ID: <31C358AA.666FFD8C@access.digex.net> References: To: VE4KLM VE4KLM wrote: > Can anyone give me dimensions for a .001 microhenry strip, and also maybe > some strip line formulas, so that I can create my own inductors. The impedance looking into a lossless, shorted transmission line is Z0 tan Bl where B is the 2*PI/Lambda (in the medium), l is the length of the line and Z0 is the charact eristic impedance. There are many sources obtaining Z0 for varios geometries (single wire above a ground plane, a strip above a ground plane are popular). You'll find it hard to get much above 200 ohms for a microstrip line (and it's useful to have a Hi Z0 to keep the line lengths down). -- |\ _,,,---,,_ Michael Katzmann ( NV3Z / VK2BEA / G4NYV ) /,`.-'`' -. ;-;;,_ - Broadcast Sports Technology Inc. |,4- ) )-,_. ,\ ( `'-' - Odenton, Maryland. U.S.A. '---''(_/--' `-'\_) michaelk@digex.NET (finger for PGP public key) From amsoft@epix.net Wed Jun 19 21:10:44 1996 From: macino@mail.fwi.com Newsgroups: rec.radio.amateur.antenna Subject: Re: help me build .001 microhenry inductor (stripline or piece of wire ?) Date: 18 Jun 1996 05:56:47 GMT Message-ID: <4q5gev$d9l@news.fwi.com> References: <4pkub8$i7b@li.oro.net> Reply-To: macino@mail.fwi.com In <4pkub8$i7b@li.oro.net>, rst-engr@oro.net (Jim Weir) writes: >VE4KLM shared the following priceless pearls of >wisdom: > > >->I am building a 6th order butterworth bandpass filter for the 2 >meter >->band >->Can anyone give me dimensions for a .001 microhenry strip > >Well, since .001 uH = 1 nH, and since #22 wire is about 20 nH per inch >in straight wire, about 50 thou of wire will do it. Point being, this >is an impossibly small inductance to deal with. > >Jim > >Jim Weir VP Engineering | You bet your sweet patootie I speak for the >RST Engineering | company. If I don't, ain't nobody gonna. >Grass Valley CA 95945 | >http://www.rst-engr.com | AR Adv WB6BHI--FCC 1st phone---Cessna 182A N73CQ >rst-engr@oro.net | Commercial/CFI-Airplane/Glider-A&P-FAA Counselor > Howdy, According to Coil_2.exe which is supposedly on the June 1996 QRZ CD-Rom. A 1 turn, 1 inch overall length of wire, .21 inch inside diameter will give yo u a 001007309 uh inductor. Use a drill bit for that .21 i.d. Jim WD9AHF From amsoft@epix.net Wed Jun 19 21:10:45 1996 From: mpfb8@central.susx.ac.uk (Peter Reed) Newsgroups: rec.radio.amateur.antenna Subject: Re: Help! 6 mtr antenna problem Date: 14 Jun 1996 07:42:54 GMT Message-ID: <4pr55u$2ab@infa.central.susx.ac.uk> References: <4piadd$ccu@nnrp1.news.primenet.com> Monty Wilson (mwilson@bangate.compaq.com) wrote: : Matt Strandberg wrote: : >I recently tried to make a 6 mtr vertical antenna. I made a normal : >coaxial-fed dipole... : > : >Then, I turned the antenna vertical... : > : >The SWR is 4:1, and I am sure that the lengths are correct. I am using : >No. 16 insulated copper wire, and I can't figure out why it doesn't : >perform properly.... : A couple of questions, Matt. Did you ever measure the SWR while the : dipole was oriented horizontally? This might tell you if the ground : or some other nearby object is affecting the SWR. : Also, the 468/f formula only gets you close, normally it comes out a : little long and you have to trim the ends down to get to 50 ohms. Is : there a resonant point anywhere that you can find? : If you're using an HF SWR meter, it probably works well enough for : comparison (relative) measurements at 6 meters, but the accuracy in : real numbers is probably not correct. .......and, does the coax (assuming a coax feed) come away at right angles from the vertical dipole, i.e. the coax should be horizontal relative to the vertical antenna.....? Peter, G4BVH P.L.Reed@sussex.ac.uk From amsoft@epix.net Wed Jun 19 21:10:46 1996 From: jvaldes Newsgroups: rec.radio.amateur.antenna Subject: Re: Help! 6 mtr antenna problem Date: Fri, 14 Jun 1996 10:27:24 -0400 Message-ID: <31C176CC.78A9@whoi.edu> References: <4piadd$ccu@nnrp1.news.primenet.com> Siegfried Rambaum wrote: > > > I recently tried to make a 6 mtr vertical antenna. I made a normal > > coaxial-fed dipole, with the correct length of wire. I measured it five > > times just to be sure. > > > > Then, I turned the antenna vertical, so that the wire was running "up > > and down", so that it would be a vertically polarized antenna, for FM, > > rather than an SSB/CW type antenna. > > > > The SWR is 4:1, and I am sure that the lengths are correct. I am using > > No. 16 insulated copper wire, and I can't figure out why it doesn't > > perform properly. Any information would be much appreciated. > > Did you consider the velocity factors? > Even copper wire has some velocity factor > Did you use an impedance transformer? > If not, read about the impedance matching basics. Some ferrite beads > over the end of the coax (near the antenna) might help already... > > Else, you gave too few information about your antenna to figure, what > might be wrong. How is the feed line connected to the antenna and what are the element lenghts? Given the insulated wire I might expect that they would have to be a little shorter than the standard 1/2 wavelength dipole. The feedline must be perpendicular from the plane of the radiator, i.e., for a verticle dipole the feedline should have a horizontal run of at least 1/4 wavelength (I think that's right), check one of the handbooks. From amsoft@epix.net Wed Jun 19 21:10:48 1996 From: Anargiros Rentezelas Newsgroups: rec.radio.amateur.antenna Subject: Help! Need book(s) on how to start amateur and professional radio stations Date: Fri, 14 Jun 1996 18:07:03 -0700 Message-ID: <31C20CB7.FC@compulink.gr> Dear group, Can someone please help me end my total ignorance by giving me a list of books on how to start an amateur and professional radio station. Thanks. Anargiros From amsoft@epix.net Wed Jun 19 21:10:49 1996 From: KD1YV Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Hopeless to run HF voice at 100 watts? Date: Mon, 17 Jun 1996 23:48:05 -0300 Message-ID: <31C618E5.3567@ix.netcom.com> References: charles copeland wrote: > > I recently got my general, and have trying my luck on HF voice > using a TS820 running 100 watts, antenna tuner, and a 64 foot folded > dipole at 7' in my first floor apartment (also a Carolina Bug Catcher > sitting on mag mount on floor with two 30' folded counter poise wires). > > My luck has been rotten, (with exception of 10 meters). I've talked > to three HAMS on 20 meters only to have to struggle just to get > them to recognize my callsign. > > This brings up my question: Is it hopeless to run HF voice at 100 watts? > > If I were to get a inverted V dipole up at 40' would I have the same > lousy luck? What cheap portable antenna would be most efficient? > > I know two other HAMS who have recently gotten their general, > and both report lousy results on 20m-160m running 100watts. > Both live on third floor apartments using folded dipoles. Both rarely > are able to snag a QSO. > > What about running mobile? A 6' whip should pale to a 60' dipole on 3d floor ? > Seems 100 watts and a whip would be worse than hopeless. > > Is 100 watts sufficient when the sunspot cycle picks up? > > Are 20m-160m bands strictly the domain of the "big guns" > running 1500 watts, 100 foot towers, and monster beams? > > If this is so, what is the minimum setup to operate effectively? > > 400 watts, 600 watts, 1000 watts? > > 30', 40', 60', 100', tower? > > antennas? Charles, First, congratulations on your recent upgrade. What is your callsign? I run from 100 to 150 watts (depends on what kind of mood my old Hallicrafters SR-400A is in that day), and have had phenomenally good luck with it. I use a G5RV th at I made myself, up at about 45 feet, through an MFJ mobile tuner (300 W rating.) I rarely have any problem making a contact, and have even broke through my sha re of pileups. I have worked a fair bit of DX, including Antartica, Australia, New Zealand, Marshall Islands, and a few African stations, not to mention a ton of Europe, Caribbean and South America. And all of this within the last year, at the "bottom" of t he sunspot cycle. Most of my contacts are on 75 or 20 meters, since my old rig has no WA RC bands. It really sounds like your antenna situation needs to be improved, and it will make all of the difference in the world. 73 de Jim, KD1YV From amsoft@epix.net Wed Jun 19 21:10:50 1996 From: jjmartin@shore.net (Jim Martin) Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Hopeless to run HF voice at 100 watts? Date: Tue, 18 Jun 1996 21:08:00 GMT Message-ID: <4q6ra0$6jt@shore.shore.net> References: Reply-To: jjmartin@shore.net charles1@netcom.com (charles copeland) wrote: >This brings up my question: Is it hopeless to run HF voice at 100 watts? I was stationed in Korea (South of course) from June of 1989 to June of 1990 and obtained the call of HL9ZF whilst there. I was billeted on the second floor in what are now Korean condos. Anyway, I used a Hustler MO-2 mobile mast with the 10, 15, and 20 meter resonators and had it attached to the rail on the balcony. I worked Montevideo (sp?) in Uraguay on 10 meters running only about 60 or 70 watts. Can't get any farther than that....it's half way, almost to the mile, around the world. =========================================== cheers! jim martin, wk1v lowell, mass http://www.shore.net/~jjmartin/jjm.htm From amsoft@epix.net Wed Jun 19 21:10:52 1996 From: "Thomas W. Castle" Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Hopeless to run HF voice at 100 watts? Date: Tue, 18 Jun 1996 05:02:17 -0400 Message-ID: References: To: charles copeland In regards to only running a 100W, I basically only use 80-100W... I run 7.251, 7.248, 14.305, 3847.5, 3945 in the mobile an at home. At home I use a G5RV up about 40' with my IC-751 an Dentron Ant tunner. I also work digital modes on 20, 40 & 80 at about 50W out due to the heavy duty cycle on Pactor, Amtor & ect. Its not so much the power, my mobile Atlas 210X only does 80-100w at best, its how you get it to the antenna an type of antenna. The people I talk with on a routine basis have no problem hearing me, even if I'm not the strongest station they ever heard... Your going to have to look hard at your antenna system, are re-consider its layout or feed line or other factors which would apply... I know this doesn't solve your problem, it just understates the fact that a antenna system can either make or break you... Just remember if your S-5 on a 100w, and if every time you double your power you could come up 1 S unit; what would your signal be at 800W..? 100, 200, 400 & 800w Figure it out... Its not the difference of S-5 to 60/9... either. There are some really sharp guys here on this newsgroup, an they will probably have much better ideas on what you might need to do, than me. Just don't give up... 73 De Tom From amsoft@epix.net Wed Jun 19 21:10:54 1996 From: AC6V Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Hopeless to run HF voice at 100 watts? Date: Wed, 19 Jun 1996 08:52:23 -0700 Message-ID: <31C82237.55CC@ix.netcom.com> References: To: charles copeland charles copeland wrote: > > I recently got my general, and have trying my luck on HF voice > using a TS820 running 100 watts, antenna tuner, and a 64 foot folded > dipole at 7' in my first floor apartment (also a Carolina Bug Catcher > sitting on mag mount on floor with two 30' folded counter poise wires). > > My luck has been rotten, (with exception of 10 meters). I've talked > to three HAMS on 20 meters only to have to struggle just to get > them to recognize my callsign. > > This brings up my question: Is it hopeless to run HF voice at 100 watts? > > If I were to get a inverted V dipole up at 40' would I have the same > lousy luck? What cheap portable antenna would be most efficient? > > I know two other HAMS who have recently gotten their general, > and both report lousy results on 20m-160m running 100watts. > Both live on third floor apartments using folded dipoles. Both rarely > are able to snag a QSO. > > What about running mobile? A 6' whip should pale to a 60' dipole on 3d floor ? > Seems 100 watts and a whip would be worse than hopeless. > > Is 100 watts sufficient when the sunspot cycle picks up? > > Are 20m-160m bands strictly the domain of the "big guns" > running 1500 watts, 100 foot towers, and monster beams? > > If this is so, what is the minimum setup to operate effectively? > > 400 watts, 600 watts, 1000 watts? > > 30', 40', 60', 100', tower? > > antennas? Hi Charles. The sunspot cycle is at or near its low point for the cycle, so the upper bands are very poor -- I suspect this is part of your problem -- as it is with the rest of us. Second the power out is not anywhere near as important as your antenna. And No you don't need a huge tower and a beam. Several of us here in San Diego with antenna restrictions have Cushcraft and Hy-Gain antennas such as the R5, R7 and DX-77 and are quite successful at working DX when the bands are open. These antennas are mounted at 6 to 10 feet off the ground and since they are "half wave end fed antennas" they work quite well without radials. These verticals have a good low angle of radiation for DXing. One of our group on the San Diego DX Cluster has worked 104 countries with 6 watts and an R5. These may sound "incredible" unless you have tried it, turns out from 6 Watts to 96 watts is about 12 dB or roughly 2 S-units. So the 6 watter compared to the 100 watter is down 2 S-units or so. With 6 watts, several 10,000 mile plus contacts and QSL cards are in the log. For dipoles, inverted Vees and beams -- you need to get em up in the air, as the radiation patterns are strongly influenced by height. In general, the higher these antennas are -- the lower the radiation pattern. That is why the big towers for the beams and dipoles. Note that a properly designed vertical can work well at or near ground level. And no, the 160-20M bands are not the exclusive territory of the "Big Guns". I know several DXers who have worked DXCC with 100 watts and antennas at 40 + feet as well as DXCC with 6 watts and a vertical as mentioned before. During the last hours of a contest or the last days of a big DXpedition, many times the DX is begging for contacts --- easy pickins. So hang in there -- when the sunspot cycle starts to pick up, you can work 10M DX with a wet noodle and a coupla watts. I know of one DXer who loaded up his rain gutters and worked many Asian African and Europeans on 10 Meters. 73 and Good Dx Rod The R5er -- _______________________________________________________________ A Man May Know Of The Whole World Without Leaving The Shelter Of His Own Home. ..... Lao Tze Hark! For I Have Hurled My Words To The Far Reaches Of The Earth! What King Of Old Could Do Thus? ..... AC6V _______________________________________________________________ From amsoft@epix.net Wed Jun 19 21:10:55 1996 Newsgroups: rec.radio.amateur.antenna From: psoper@encore.com (Pete Soper) Subject: Ladder line variability questions Date: Mon, 17 Jun 1996 17:15:49 GMT Message-ID: As I grease up my VISA card to buy another few hundred feet of ladder line I'm bothered by W8JI's posting some months back about some ladder line he got that was way off the expected impedance. For a Lazy-H project I need the highest impedance I can get for the phasing lines, but also absolute minimum weight and good durability, as they will be dancing a lot in the wind. So I'm leaning toward Wireman #553, which is listed as 450 ohm line with #18 stranded conductors. Has anybody measured a sample of this? Likewise, for the feed from the junction of the phasing lines I'm going with 300 ohm line, but need to know ahead of time that it really is 300 ohms. Here's my basic question. It seems that the various flavors of line, with different conductor sizes, must be different widths to maintain the target impedance. For instance, it seems impossible that if "vanilla" 300 ohm ladder line has #20 conductors, the type with #18 conductors could be the same width. But I've never seen more than one size each of 450 and 300 ohm slotted lines, no matter what the conductor size. Likewise, I see 450 ohm line with everything from #18 to #14 conductors. The little bit I (think) I know about how balanced line impedance relates to conductor size and spacing would suggest either these different lines are different widths, or else the "450" and "300" designations are bogus. What's the real story here? Incidently, plugging the numbers into the EZNEC transmission line modeler, I can't come up with a plausible 300 ohm ladder line, based on the dimensions and wire gauges I'm familiar with. That is, #20 conductors spaced around 1/2 inch comes out way, way over 300 ohms. The model predicts 303 ohms for two #20 conductors spaced .2 inches apart: much closer spacing than the conductors in the 300 ohm slotted line I'm using for my tuner project . I must be missing something fundamental about all of this. And I suddenly have an urge to measure that "300" ohm line when I get home :-) Regards, Pete KS4XG From amsoft@epix.net Wed Jun 19 21:10:57 1996 From: kferguson@aquilagroup.com (Kevin AstirCS "1U" KO0B) Newsgroups: rec.radio.amateur.antenna Subject: Re: Magic Raibeam 2 el array Date: Wed, 12 Jun 1996 17:56:41 -0700 (PDT) Message-ID: <4pnld9$vrh@blixen.aquilagroup.com> References: <8C24317.02CF0013DB.uuout@cencore.com> forrest.gehrke@cencore.com (FORREST GEHRKE) wrote: >They claim a F/B ratio greater than 25dB and twice the >gain of a 2 el Yagi for this 20M version. Can you >believe it, all on a 7.125 ft. boom? Note: I am an no way supporting any manufacturers claims of gain...But the underlying premise, "longer must be better" of the above posting, bears looking into. The short boom isn't so amazing. Short Yagis, for example, _ can_ show much better F/B and forward gainthan long ones....at the expense of very low feed impedance, and poor bandwidth. (law of free lunches at work) With two elements, for perfect cancelation of rearward lobes (infinite F/B) you would need _equal_ currents flowing in the two elements..of course with the proper phase relationship....but if they are not of same magnitude you can't get 100% cancelation, regardless of phasing. With a Yagi, you have a tradeoff situation...to couple reflector most strongly to driven element, (to get currents as close to equal as possible) you need to be at resonance, but then you have to detune to get the required phase shift. You want to be close for good coupling, but that lowers radiation resistance, and hurts bandwidth....compromise, compromise, compromise. If you could have independant control of coupling, and phasing, I would expect that much higher f/b could be achieved...and driving both elements could achieve this. But it surely opens a whole nuther can of worms....namely the low feed impedances, actually producing the required phase shifts into the VERY reactive elemnts, etc. Close spacing also improves forward gain...the two elements are running much closer to 180 deg phasing, so upward and downward radiation is cancled to a much higher degree for close spacing, than for far spacing. The improvement in f/b and f/top ratio leaves more radiation to go into forward lobe. Imagine a long, 1/4 wave boom for example. You would want the two elements in quadrature, so you only get 3dB (relative to front lobe) cancelation of upward radiation. Compare to a 7.125 foot boom, or 37 degrees spacing, driven at 143 deg ( for best f/b ratio) would give you 5.5 dB front/top. (back of envelope calculation...by a no NEC!) Note that the two elements driven at close to 180 deg. cancle FORWARD radiation to a substantail degree! This is why the radiation resistance goes into the cellar. The cancelation does not result in a decrease in forward gain, exept that it will produce very high circulating currents in the elements, and required phase shifting /feed matching networks, the resulting losses will likely piss away most /all/and then some of the advantages of the short boom. No, short booms are not very popular. The squirelly impedances, and low radiation resistance present substantial problems in practice..... Theoretical analysese which do not take losses of real elements coils, etc. into account will yield deceptively optimistic performance expectations. I guess my point is, that to claim such outstanding performance figures for a two element arrray, it would almost _have_ to be a short boom design. If I'm wrong, somebody will surely correct me. If I'm right, somebody will surely correct me -73- ko0b From amsoft@epix.net Wed Jun 19 21:10:57 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Magic Raibeam 2 el array Date: 13 Jun 1996 11:13:50 -0400 Message-ID: <4ppb7e$go2@newsbf02.news.aol.com> References: <4poe23$hu0@lehi.kuentos.guam.net> In article <4poe23$hu0@lehi.kuentos.guam.net>, pacrimgolf@kuentos.guam.net (Jim Kehler) writes: >The East Bunny lays eggs in the front yard. Colored eggs. And >sometimes plastic ones with candy inside. > >So come on Armond, if you don't know what you're talking about, look >it up in the ARRL antenna handbook before you post it next time. > >73, Jim KH2D That's right, and the Easter Eggs are never conjugately matched. If they were, the Easter Bunny's work would only be 50% eggficient. The Blooming Bunny Theory:] In some baskets the eggs have to be hallow, in other baskets filled with lead. What egg you put in what basket is determined by the side of the bed. It's all in the Awful Rabbit Rearend Leavings Handbook. 73 Tom From amsoft@epix.net Wed Jun 19 21:10:58 1996 From: D.N.Muir@massey.ac.NZ (Dexter N. Muir) Newsgroups: rec.radio.amateur.antenna Subject: Missing back-issues Date: 15 Jun 96 22:31:20 GMT Message-ID: <199606152231.PAA17926@UCSD.EDU> Greetings, all, from New Zealand! I keep an archive of this Digest on my 24-hrs Packet station for local Hams who have no Internet. Occasionally (though rarely), either UCSD or my (Massey) mail server hiccups, and I lose one or two issues. I would like to keep the archive complete, so am seeking issue: V96 #300 (27 May) If any kind soul has kept this, I would appreciate a copy (to email address below). Meanwhile, many thanks to Brian, and to all contributors. Thanks in advance, and 73 de Dexter, ZL3LH -------------------------------------------------------------------------- | Dexter N. Muir Manufacturing Pilot Plant Technician | | D.N.Muir@massey.ac.nz Department of Production Technology | | Massey University, Palmerston North, New Zealand | | http://www.massey.ac.nz/~DNMuir/ | | "Honesty pays --- but not enough." "Modesty pays --- but even less!! " | -------------------------------------------------------------------------- From amsoft@epix.net Wed Jun 19 21:10:59 1996 From: (Steve Greenberg) Newsgroups: rec.radio.amateur.antenna Subject: Mobile Antennas?? Date: 17 Jun 1996 15:43:02 GMT Distribution: world Message-ID: <4q3ue6$msc@news2.aero.org> Hi I am interested to know about experiences with the various dual band antennas on the market (comet, ANLI, Larson, ect.). What are your likes and dislikes? Is there a preferred mounting style? Thanks for the help. 73s Steve, WA6TAF From amsoft@epix.net Wed Jun 19 21:11:00 1996 From: Will Flor Newsgroups: rec.radio.amateur.antenna Subject: Re: Mobile Antennas?? Date: Wed, 19 Jun 1996 12:04:31 -0500 Message-ID: <31C8331F.39F9@rrgroup.com> References: <4q3ue6$msc@news2.aero.org> Steve Greenberg wrote: > > Hi > > I am interested to know about experiences with the various dual band > antennas on the market (comet, ANLI, Larson, ect.). What are your likes > and dislikes? I've had good results with Larsen, but I've never used anything else, so I can't really compare them to other brands. >Is there a preferred mounting style? Thanks for the help. > Best: cut a hole in the car and permanently mount it. Second best: mag-mount Third best: trunk-lip or other non-glass mount Last: glass mount Nevertheless, I have had results that are quite good with a glass-mount Larsen 2m/70cm antenna. I don't transmit with power over 10 watts with it, however, since there is noticeable feedline radiation, due to no connection to the car's body at the antenna. 73 de KB9JTT From amsoft@epix.net Wed Jun 19 21:11:01 1996 From: "Deni Watters (WB0TAX)" Newsgroups: rec.radio.amateur.antenna Subject: Multi-Band Verticals Date: Sun, 16 Jun 1996 16:54:02 -0500 Message-ID: <31C4827A.41C67EA6@dwatt.com> I am soon to install a multi-band vertical and I desire to ground mount the antenna. I am also not interested in installing a radial system. The antenna will be used for 95% CW. What are your experiences? What are you using? Wha t do you recommend and why?? Prefer responses to my email address. Thanks and 73 Deni WB0TAX ------------------------------------------------------------------------------ Dennis `Deni` Watters | Owner, President, CEO, Chairman of the Board WB0TAX | THE DUN MUVN FARM deni@dwatt.com | unless of course, my wife overrules me! http://www.dwatt.com | she has the checkbook. ------------------------------318-747-2823------------------------------------ From amsoft@epix.net Wed Jun 19 21:11:02 1996 From: vjkunesjr@fingerlake3.com Newsgroups: rec.radio.amateur.antenna Subject: Need help feeding 80 mtr loop Date: 14 Jun 1996 17:23:15 GMT Message-ID: <4ps763$rp@news.paonline.com> Now that I aqm about to put 279.2 feet of copper in the air for a 80 meter llo op, there is only one question I could use some help on, since I am a neophyte when it comes to wire antennas. I have read in this newsgroup that the feed point of this 80 meter loop is going to be around 100 ohms. I plan feeding it with 213 and usi ng it on all bands thru a MFJ 949 tuner. In a message in this news group on this subject, someone said that a 4:1 balun should be used. It seems to me that 100 to 50 or 25 to 50 still comes out 2:1. Is there some other reason for putting the 4:1 balun in the line (I w as wondering if it has something to do with easier matching at higher freqs). Sorry to sound so ignorant, but I guess at this subject at this time, I am as I sound. Any help appreciated. Thanks 73 de N2YZS From amsoft@epix.net Wed Jun 19 21:11:03 1996 Newsgroups: rec.radio.amateur.antenna From: n4lq@iglou.com (Steve Ellington) Subject: Re: Need help feeding 80 mtr loop Message-ID: References: <4ps7di$1or@news.paonline.com> Date: Sat, 15 Jun 1996 03:06:04 GMT You'll get a lot of different answers on this one. Most will advocate using open wire feeders all the way to the tuner. Heres what I do on my 160m loop for multiband use. At the feed point, use a 4:1 CURRENT balun. These are available from Radio Works as either a kit or assembled. Inside them are 100 ferrite beads and some RG-92 coax. They seems to have very stable characteristics across the HF spectrum compared to the traditional 4:1 voltage balun. I then run my RG-8 straight down to the shack. It's about 60ft long. I cut my antenna for the lowest part of the cw band. My SWR (readings) (at the rig), note how I qualified that, are below 3:1 on any band. On harmonics like 80, 40, 20, 15 and 10 meters, my swr is less than 2:1. The balun does not overheat while running a KW. I learned the balun trick after 3 years of experimenting and umpteen baluns. Give one a try! vjkunesjr@fingerlake3.com wrote: : Now that I aqm about to put 279.2 feet of copper in the air for a 80 meter l loop, there is only one question I could use some help on, since I am a neophy te when it comes : to wire antennas. I have read in this newsgroup that the feed point of this 80 meter loop is going to be around 100 ohms. I plan feeding it with 213 and u sing it on all bands : thru a MFJ 949 tuner. In a message in this news group on this subject, someo ne said that a 4:1 balun should be used. It seems to me that 100 to 50 or 25 t o 50 still comes : out 2:1. Is there some other reason for putting the 4:1 balun in the line (I was wondering if it has something to do with easier matching at higher freqs) . Sorry to sound so : ignorant, but I guess at this subject at this time, I am as I sound. Any hel p appreciated. Thanks 73 de N2YZS -- Steve Ellington N4LQ@IGLOU.COM Louisville, Ky From amsoft@epix.net Wed Jun 19 21:11:03 1996 From: billv21572@aol.com (BillV21572) Newsgroups: rec.radio.amateur.antenna Subject: Need Windom antenna experiences... Date: 14 Jun 1996 00:24:46 -0400 Message-ID: <4pqpie$524@newsbf02.news.aol.com> Reply-To: billv21572@aol.com (BillV21572) I'm sure this thread has gone by already, but being in a constant state of antenna experimenting, I'm now considering a Windom antenna, primarily to gain 80 meter band exposure which I don't have with my vertical. I've got the real estate for an off-center fed antenna like this one, but not really for a true 1/2 wavelength 80 mb dipole (nor the height!). A Windom would also offer me multiband capabilities, complementing my vertical. A friend of mine tells me his has wide bandwidths all without an antenna tuner. Any Windom users, past and present: does off-center feeding and a radiating vertical portion add up to reasonable performance for the investment? Thanks in advance for any help on this. 73 de Bill ka9hln Bill Vanstralen KA9HLN St. Paul, MN (612)688-2552 billv21572@aol.com From amsoft@epix.net Wed Jun 19 21:11:04 1996 From: Wayne Carlson Newsgroups: rec.radio.amateur.antenna Subject: Pro-Am (Valor) dual band antenna? Date: Sat, 15 Jun 1996 08:19:33 -0700 Message-ID: <31C2D485.5417@rtd.com> Does anyone have experience with the Pro-Am DB240 antenna? How it is electrically and mechanically? -- Wayne Carlson -- carlson@rtd.com -- K2DT -- Tucson, AZ From amsoft@epix.net Wed Jun 19 21:11:05 1996 From: vjkunesjr@fingerlake3.com Newsgroups: rec.radio.amateur.antenna Subject: Re: Question about antennas Date: 14 Jun 1996 03:58:15 GMT Message-ID: <4pqo0n$l3f@news.paonline.com> If you could put up an 80 meter loop 20 or so feet up, I think you would find it to be a very good antenna (and also quiet). If you have the room and the su pport for it, it is an inexpensive antenna to use. Good luck. Vern N2YZS (I started at Tech+ and don't regret it!) From amsoft@epix.net Wed Jun 19 21:11:06 1996 From: joes@halsey.com (Joe Sullivan) Newsgroups: rec.radio.amateur.antenna Subject: Question about feeding my long wire Date: 17 Jun 1996 01:16:41 GMT Message-ID: <4q2blq$k1o@news0.rain.rg.net> I plan on putting up a long wire on my property. I think that I could probably string up about a 200 foot wire. I am using an MFJ 949E tuner with a connection on the back for a long wire. My problem is ... Am I supposed to bring this bare, long wire into my shack where people can touch it? If It is supposed to run directly into my shack then are there any precautions that I should take, like avoiding sharp turns? having it touch metal? How is this normally done? The ARRL antenna book seems to be silent on this subject. What is the preferred method of hooking this wire into my shack? Respond here or to Joes@rtinet.com Thanks, KB7UEF From amsoft@epix.net Wed Jun 19 21:11:08 1996 From: rpmarkey@nbn.NET (Rick Markey KN3C) Newsgroups: rec.radio.amateur.antenna Subject: REWindom Date: 14 Jun 96 10:43:52 GMT Message-ID: <01BB59BC.DEB750A0@access6.nbn.net> Date: 14 Jun 1996 00:24:46 -0400 From: billv21572@aol.com (BillV21572) Subject: Need Windom antenna experiences... I'm sure this thread has gone by already, but being in a constant state = of antenna experimenting, I'm now considering a Windom antenna, primarily = to gain 80 meter band exposure which I don't have with my vertical. I've = got the real estate for an off-center fed antenna like this one, but not really for a true 1/2 wavelength 80 mb dipole (nor the height!). A Windom = would also offer me multiband capabilities, complementing my vertical. A = friend of mine tells me his has wide bandwidths all without an antenna tuner.=20 Any Windom users, past and present: does off-center feeding and a radiating vertical portion add up to reasonable performance for the investment? Thanks in advance for any help on this. 73 de Bill ka9hln Bill, I used a "classic" windom at 2 different locations with good = success. By "classic", I mean single wire feed and roughly 130' in = length. I brought the single wire feed into the house with a feed-thru = insulator, as well as a ground connection from an outside ground rod. = On the inside of the house was a short piece of ladder line which = connected to a Johnson Matchbox. In both cases, the antenna worked = well, however I never compared it to a dipole cut for a specific band. = I worked mostly 80 and 40 with it, and was also able to work 160. The = single wire version is prone to RF in the shack, so beware. If you = physical layout dictates a Windom, go for it. de Rick, KN3C From amsoft@epix.net Wed Jun 19 21:11:09 1996 From: w7el@teleport.com (Roy Lewallen) Newsgroups: rec.radio.amateur.antenna Subject: Re: S-Meter values Catalogue Date: Fri, 14 Jun 96 17:50:06 GMT Message-ID: <4ps8mt$lkt@nadine.teleport.com> References: <4pq6pj$4i2@roch.zetnet.co.uk> <31C150F3.41C67EA6@nt.com> In article <31C150F3.41C67EA6@nt.com>, Dave Ward wrote: >Why not just have the S-meter calibrated to an existing, well defined unit >of measurement like dbm? I really don't see the need for a precisely defined >S unit when an an existing unit will work. > >Is there any technical problem with this? How difficult would it be to make a >meter circuit that would read over a range of something like 70 db with an accuracy >of +- 3 db for the frequency ranges of interest, say 1-30 MHz? > >Dave VE3BIP It would require a different approach to amateur receiver design than is taken today. Current receivers have an AGC system whose sensitivity varies more-or-less logarithmically with AGC voltage. The S-meter simply measures the AGC voltage. To make the S-meter truly logarithmic would require redesign of the IF and/or RF section for true logarithmic response to the AGC voltage. Alternatively, the receiver can be designed like a spectrum analyzer which has good wide-range logarithmic response, and the meter can then measure the actual signal strength. In these, the front end is designed to handle an extremely wide range of signal amplitudes with very little distortion, but is not AGC controlled. Then the IF has a true logarithmic response. Either approach would require a lot of development time and a different philosophy on the part of the receiver manufacturers, in addition to increased manufacturing cost. Would amateurs pay enough extra for an accurate S-meter to make it worthwhile for them? I seriously doubt it, and apparently so do the manufacturers. Roy Lewallen, W7EL From amsoft@epix.net Wed Jun 19 21:11:11 1996 From: n7tcf@primenet.com Newsgroups: rec.radio.amateur.antenna Subject: Re: S-Meter values Catalogue Date: 13 Jun 1996 05:50:01 -0700 Message-ID: <4pp2pp$g38@nnrp1.news.primenet.com> References: <4p579c$eki@mark.ucdavis.edu> <4p9qoc$16uo@chnews.ch.intel.com> <4pbgfi$t80@nadine.teleport.com> <4pf7l6$d04@nadine.teleport.com> <31BCDA8A.7D83@chass.utoronto.ca> Reply-To: n7tcf@primenet.com This would provide a useful reference, since the US General class test questio n pool gives credence to S units. Many hams are suprised to find S-units have no scientific reference. I think Collins tried to do this once as well. Jim N7TCF >Roy's comments got me thinking. A list of S-meter to dB conversion >tables for common rigs really would help everyone. We could make it a >list project, for those of us who have access to the equipment. Take >your rig to the lab, run the test, and post it to the list where I or >others will make a web page out of all the results. > >Two questions abide: > >1. Is is safe to assume that all rigs of a certain model exhibit >identical dB between S-meter values? > >2. What is the right way to do this test with tools you might find >around the home/lab ? > >3. Should the test be done for each band? From amsoft@epix.net Wed Jun 19 21:11:11 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: S-Meter values Catalogue Date: 17 Jun 1996 11:08:10 -0400 Message-ID: <4q3scq$61d@newsbf02.news.aol.com> References: <4pr66j$a21@nadine.teleport.com> In article <4pr66j$a21@nadine.teleport.com>, w7el@teleport.com (Roy Lewallen) writes: >Wouldn't it be nice if we could make all our S meters read in uniform 6 dB >increments by defining the S-Unit to be 6 dB? While we're at it, let's >define 1:1 SWR to be any condition with less than 100% reflected power. >Then we can all have 1:1 SWR, too. > >Roy Lewallen, W7EL > > An excellent idea Roy! Perhaps we could define define "gain" as the number and length of conductors in our antenna compared to a reference dipole. A folded dipole would have 3 dB gain, a coaxial dipole 3 dB, a linear loaded antenna with two wl of wire would have 6 dB gain. It even works perfectly for a quad, now it has 3 dB gain in each element over a yagi. 73 Tom From amsoft@epix.net Wed Jun 19 21:11:13 1996 From: Jim Reid Newsgroups: rec.radio.amateur.antenna Subject: Re: S-Meter values Catalogue Date: Mon, 17 Jun 1996 14:57:25 -1000 Message-ID: <31C5FEF5.44B6@aloha.net> References: <4q4fib$lpk@roch.zetnet.co.uk> Reply-To: jreid@aloha.net Frank Dinger wrote: --snip-- > Please also see a response from VE3BIP on this topic . > He proposes to use the 'dbm' as unit of signal strength . > Also the introduction of the dbm for S-meter readings would be a > cultural shock to many hams . Given that 0 dBm is 0.001 watt (1.0 milliwatt, or 1 mW), then one-half microvolts across a 50 ohm resistor is dissipating -113 dBm of power. So, the S-scale conversion would become: S-9 -73 dBm S-8 -79 S-7 -85 and so on down, dropping 6 dB per S-unit, to S-1 -121 dBm. Note that the ARRL labs report that most modern transceivers have CW sensitivities of around -135 on down to -142 dBm, presumably run with the 500 Hz CW filters in place to knock down the thermal noise levels for these numbers to be real. BTW, an excellent book covering this topic is ON4UN's book "Low Band DX'ing". He avers that for an SSB signal, when using 3 kHz bandwidth filters, the reciever noise floor will be at -129 dBm. He says that good operators need about 10 dB signal to noise ratio to read a weak DX signal, or that the input signal level must be about -119 dBm. Just a couple dB stronger than an S-1 signal of -121 dBm. Where did John get -129 dBm? Well he was using a Yaesu FT-1000D, which has an ARRL measured min signal capability of -137 dBm, per the ARRL labs. Now the actual thermal noise in a 500 Hz bandwidth of spectrum is -147 dBm, per the old standby kTB formula. The added 10 dB by the FT-1000D measured by the ARRL is the rigs added noise, or its noise figure. The figure John uses, -129 dBm, is the added lift in the noise floor when the bandwidth is increased from the 500 Hz used by ARRL to the 3 kHz bandwidth of which John is writing; that is 6 x's the bandwidth or, 7.7 dB(pretty close to John's added 8 dB. So, hooray, it all works out, just as it should! It would be nice if our signal strength meters on our affordable rigs could read out with these nice accruacies and absolute dBm figures, but am afraid not many of us could afford the cost of, essentially an hp HF Spectrum Analyzer as part of our rigs front end! 73, Jim, AH6NB From amsoft@epix.net Wed Jun 19 21:11:15 1996 From: frank.dinger@zetnet.co.uk (Frank Dinger) Newsgroups: rec.radio.amateur.antenna Subject: Re: S-Meter values Catalogue Date: Sun, 16 Jun 1996 21:11:02 +0100 Message-ID: <4q4fid$lpk@roch.zetnet.co.uk> In message <31C150F3.41C67EA6@nt.com> Dave Ward writes: > Frank Dinger wrote: > > It is my understanding that at an IARU Zone 1 meeting in Budapest-Hungary, > > in 1977 , 1 S unit was defined as a change of signal strength of 6 dB. > > For frequencies up to 30 MHz an S-9 signal was defined as 50 > > microvolts across 50 Ohms at the receiver input terminals and shown > > on the S-meter at max RF gain. > > > > For frequencies above 30 MHz an S-9 signal was defined as 5 > > microvolts at 50 Ohms across the receiver input terminals, etc. > > > Why not just have the S-meter calibrated to an existing, well defined unit > of measurement like dbm? I really don't see the need for a precisely defined > S unit when an an existing unit will work. > Is there any technical problem with this? How difficult would it be to make a > meter circuit that would read over a range of something like 70 db with an accuracy > of +- 3 db for the frequency ranges of interest, say 1-30 MHz? > Dave VE3BIP ======== coments GM0CSZ / KN6WH Expressing signal strength in dbm would be fine ,like in the IARU scale case ,it is based on a reference which can be reproduced in the shack. De dbm is nowadays a standard unit of measurement for RF signals levels ,hence I would be happy with a signal strength scale in dbm . Its introduction would however be a cultural shock to many hams. Has this at any time been proposed at ARRL level . I would be very happy to support the proposal. Frank Dinger , Inver by Tain , Ross-shire IV20 1RX - Scotland e-mail : gm0csz.kn6wh@ukrs.org Packet : GM0CSZ @ GB7NOS.#76.GBR.EU From amsoft@epix.net Wed Jun 19 21:11:15 1996 From: thompson@atl.mindspring.com (david l. thompson) Newsgroups: rec.radio.amateur.antenna Subject: Re: Stainless Steel wire as Antenna? Date: Fri, 14 Jun 1996 20:20:03 GMT Message-ID: <4pskfi$2gfa@mule2.mindspring.com> References: <4phteg$9c8@dfw-ixnews10.ix.netcom.com> Reply-To: thompson@atl.mindspring.com gsparks@ix.netcom.com(Glenn Sparks) wrote: >I have a beach house near Galveston, Texas, and the environment >destroys my antenna system every year. I have a 80 / 40 meter fan >dipole up about 45 feet. I have been using galvanized wire for the >guys, and copperweld for the antenna and dacron rope. First the guy >wire will rust into, about 8 months, then the copperweld will go, the >Dacron seems to hold up well though. Fritzel Antennas from Germany has used covered stainless steel wire for many years in the FD-4 dipole series. There are well over 30,000 in use worldwide. They would work very well in your type of environment. Dave K4JRB From amsoft@epix.net Wed Jun 19 21:11:16 1996 From: "C.D.Sage" Newsgroups: rec.radio.amateur.antenna Subject: Toroidal Helical Antenna --- Revolutionary New Antenna Date: Sun, 16 Jun 1996 10:42:07 -0700 Message-ID: <31C4476F.4AB2@netaxs.com> IAS Communications Inc.(1-800-668-5499) is developing this revolutionary new radio frequency antenna that is 1/60 the height(length) and weighs 80% less than most conventional applications. The Department of Defense (Navy) is currently testing the (THA) antenna. The company forsees being able to replace a 150 foot tall radio tower with a three(3) foot tall (THA) antenna. The company will provide technical info upon request. (PS) I am not an employee of this company. Regards, C.D.Sage From amsoft@epix.net Wed Jun 19 21:11:17 1996 From: w7el@teleport.com (Roy Lewallen) Newsgroups: rec.radio.amateur.antenna Subject: Re: Toroidal Helical Antenna --- Revolutionary New Antenna Date: Sun, 16 Jun 96 19:14:21 GMT Message-ID: <4q1mcq$3u6@nadine.teleport.com> References: <31C4476F.4AB2@netaxs.com> In article <31C4476F.4AB2@netaxs.com>, "C.D.Sage" wrote: >IAS Communications Inc.(1-800-668-5499) is developing this revolutionary >new radio frequency antenna that is 1/60 the height(length) and weighs >80% less than most conventional applications. The Department of Defense >(Navy) is currently testing the (THA) antenna. The company forsees being >able to replace a 150 foot tall radio tower with a three(3) foot tall >(THA) antenna. The company will provide technical info upon request. > (PS) > I am not an employee of this company. > Regards, > C.D.Sage Sigh. This isn't the same bunch that brought us the "crossed-field" antenna, by any chance? What's your source of information? Do you have any affiliation at all with this company? Roy Lewallen, W7EL From amsoft@epix.net Wed Jun 19 21:11:18 1996 From: n7ws@azstarnet.com (Wes Stewart) Newsgroups: rec.radio.amateur.antenna Subject: Re: Toroidal Helical Antenna --- Revolutionary New Antenna Date: Sun, 16 Jun 1996 16:49:05 LOCAL Message-ID: References: <31C4476F.4AB2@netaxs.com> In article <31C4476F.4AB2@netaxs.com> "C.D.Sage" writes: >From: "C.D.Sage" >Subject: Toroidal Helical Antenna --- Revolutionary New Antenna >Date: Sun, 16 Jun 1996 10:42:07 -0700 >IAS Communications Inc.(1-800-668-5499) is developing this revolutionary >new radio frequency antenna that is 1/60 the height(length) and weighs >80% less than most conventional applications. The Department of Defense >(Navy) is currently testing the (THA) antenna. The company forsees being >able to replace a 150 foot tall radio tower with a three(3) foot tall >(THA) antenna. The company will provide technical info upon request. > (PS) > I am not an employee of this company. Do they sell bridges too? BTW, this is entirely possible if you want .001% efficiency. (I didn't waste time calculating this number, it's just a guess +/-20 dB.) From amsoft@epix.net Wed Jun 19 21:11:19 1996 From: aurelio@esrac.ele.tue.nl (Aurelio Bellussi) Newsgroups: rec.radio.amateur.antenna Subject: Traps for 'BATTLE CREEK' ?? Date: 14 Jun 1996 13:57:22 GMT Message-ID: <4prr42$k28@tuegate.tue.nl> The clubstation at the University of Technology in Eindhoven,PI4TUE-PI5EHV, obtained some sketches from the designer of the BATTLE CREEK SPECIAL LOW BANDS vertical. We built our own version from the sketches using coax for the capacity needed in the two traps. We noticed during our trip to HB0 in 1994 that the tips of the coax were arcing when we applied more than 100 W to the antenna. Is there anyone that built the Battle Creek Special and if so what solution did you use to form the traps ? We intend to take the Battle Creek to HB0 again this year between 7 and 16 july and operate 160-80-40 meters from a mountain top 2010 meters above sea level. 73 de Aurelio-PA3EZL ************************************************************************ * Aurelio M.M. Bellussi, PA3EZL/AA2WH * * E-mail: a.m.m.bellussi@stud.tue.nl OR pa3ezl@esrac.ele.tue.nl * * AX25-mail: pa3ezl@on5vl.#lg.bel.eu * * ------------------------------------------------------------------ * * Eindhoven University of Technology | University of Maastricht * * dept. of Medical Electrical Eng. | dept. of Biofysics/Image Proc. * ************************************************************************ From amsoft@epix.net Wed Jun 19 21:11:20 1996 From: pip@shore.net (GeorgeS) Newsgroups: rec.radio.amateur.antenna Subject: Re: UHF / VHF TV antennas Date: 14 Jun 1996 18:53:04 GMT Message-ID: <4psceg$576@shore.shore.net> References: <4pdah5$70n@news.laser.net> In article <4pdah5$70n@news.laser.net>, a100@fairfax2.laser.net says... > >Hi, folks - sorry to intrude here, but I didn't see any other newsgroups >that discussed antennas. Can someone please point me to a FAQ or >something similar that explains how to choose a roof mounted TV antenna? >You know, the kind you fasten to your chimney with a metal strap? Also, >I do NOT mean a DSS dish or C-band dish. Just a plain-old TV antenna. >I'm sick of paying $40 / month for cable. An inexpensive solution is the top of the line radio shack UHF/VHF antenna wit h a rotor. The antenna should cost about $100, and the rotor about $50. The way an antenna picks up a distant station is to "look" in a narrow beam. Because the beam is narrow, you can often get two or more stations with the same antenna. To get the different stations you use the rotor top point at them. The other reason you need the rotor is the narrow beam makes the antenna difficult to point, and is best done from the comfort of the living room. As to specifics. The VHF (channels 2-13) use a log periodic design. All the tines are wired together, but only certain tines are active for any given frequency. This is the "big" part of the antenna. The "UHF" part uses a folded Yaggi. Only one small dipole is wired. The rest o f the small tines are attached electrically to the mast, and act as reflectors. I live on the Ma/NH border and pull in stations from Providence RI to Portland Me. If you want to read more about it, look up the ARRL and search on the Log periodic and Yaggi words. This will give you more than you want to know. regards george From amsoft@epix.net Wed Jun 19 21:11:21 1996 From: Cecil Moore Newsgroups: rec.radio.amateur.homebrew,rec.radio.amateur.antenna Subject: Re: Variable-length ladderline tuner: implementation issues Date: 17 Jun 1996 09:49:01 -0700 Message-ID: <4q429t$7qt@nnrp1.news.primenet.com> References: <199606171153.HAA10414@comm1.ab.umd.edu> Pete Soper wrote: : I got no responses to my recent posting about how to design the : R/C circuit for damping relay coils as they are de-energized. Hi Pete, I didn't see your posting. What was the subject? Are you sure it got posted? What I have done is drive the relay with double the rated voltage with a resistor in series equal to the coil resistance and a 0.1 pf cap across the coil. : My concern is that each time I flip off a relay as I switch the : tuner a noise spike will be induced into the nearby ladder line, I wouldn't recommend switching the relays with RF on them. What I do is switch the relays without RF on them, then apply RF and write down the results. From then on, simply consult the chart and preset the relay position depending on frequency. : Again, I'll initially simply hook the tuner up and see if I have : RF in the shack, but I'm trying to anticipate how to handle this : if it is an issue. I try not to anticipate problems but solve them as they arrise. Quite often an anticipated problem never occurs. : Oh, another devilish detail came when I tried to connect the ladder : line to the relay wiper contacts. I removed the internal wires : connecting the wipers to the connector pins on the other end of : the relay, figuring this would be hopeless from a balance point of : view. So now the ladder line loops comes in the end of the relay, : in line quite nicely with the two pairs of wiper arms. I cut slots in : the plastic relay covers to allow the ladder line in while expecting : to be able to seal the slot with coax-seal after everthing was : sorted out. But it turned out there still wasn't clearance for : the ladder line to pass through, so I had to abandon the plastic : covers. I kept the covers, brought the common wires out holes in the covers and fastened them to the ladder-line outside the relay cover. I found that trying to solder the ladder-line to the common moving arms caused the relay electro-mechanical sensitivity to change for the worse. I used a glue gun to seal the holes. 73, Cecil, KG7BK (W6RCA soon), OOTC From amsoft@epix.net Wed Jun 19 21:11:23 1996 Newsgroups: rec.radio.amateur.homebrew,rec.radio.amateur.antenna From: psoper@encore.com (Pete Soper) Subject: Variable-length ladderline tuner: implementation issues Date: Mon, 17 Jun 1996 15:17:34 GMT Message-ID: References: <199606171153.HAA10414@comm1.ab.umd.edu> I got no responses to my recent posting about how to design the R/C circuit for damping relay coils as they are de-energized. The Sams' Radio Engineering book rates a series resistor/capacitor circuit as third in effectiveness after a single diode or back to back diode pair for controlling high voltage as the relay coil field collapses. I'm concerned that the diode route might get me into trouble with nearby RF fields (i.e. as a nonlinear element and thus potential RFI source), but 'm not savvy enough to chose the R/C values for my relays (12 volt, 400 ohm coils), thus the posting. My concern is that each time I flip off a relay as I switch the tuner a noise spike will be induced into the nearby ladder line, attempting to break my eardrums. Perhaps this is a non-issue? Anyway, I'll go the empirical route and test for receiver "pops" after wiring up the first relay. This device I'm building is an array of seven relays spaced three inches apart on a strip of lucite. Loops of 300 ohm ladder line of larger and larger dimensions are switched in or out of the transmission line connection between an antenna and the transceiver (via a 4:1 balun and variable capacitor). The initial loops will run out from the end of their relays and be held apart with more bits of lucite or PVC while the longer loops will go up and around the back side of the shack, held in place with insulated standoffs. The goal is to arrange a 200 ohm resistive load at the balun to get an effective match with low losses. This project is my best guess about how to implement the tuner that Cecil Moore dreamed up and has alluded to in frequent postings to the antenna group. But the devil is in the details, and I'm now quite concerned that my chances of maintaining balance with all the interconnects among the relays will be poor. I'm wondering if (assuming imbalance), I might tweak the length of one side of one piece of ladder line to regain proper phase relationships? Would a dual trace scope connected to each side of the line show me lack of balance and allow this adjustment, preventing radiation from the ladder line run from the tuner to the balun (i.e. at the operating postition)? Again, I'll initially simply hook the tuner up and see if I have RF in the shack, but I'm trying to anticipate how to handle this if it is an issue. Oh, another devilish detail came when I tried to connect the ladder line to the relay wiper contacts. I removed the internal wires connecting the wipers to the connector pins on the other end of the relay, figuring this would be hopeless from a balance point of view. So now the ladder line loops comes in the end of the relay, in line quite nicely with the two pairs of wiper arms. I cut slots in the plastic relay covers to allow the ladder line in while expecting to be able to seal the slot with coax-seal after everthing was sorted out. But it turned out there still wasn't clearance for the ladder line to pass through, so I had to abandon the plastic covers. So now I have seven "open frame" relays that are going to be sitting under the floor of the end of my shack, effectively outdoors. I'm now scheming some way to keep dust and insects out of the contacts! A bit of Saran Wrap (cling film) is the only idea I have so far. Pardon me if this sounds idiotic (or IS idiotic!). I knew nothing about RF just a few months back and am learning as quickly as I can. Regards, Pete KS4XG From amsoft@epix.net Wed Jun 19 21:11:24 1996 Newsgroups: rec.radio.amateur.homebrew,rec.radio.amateur.antenna From: psoper@encore.com (Pete Soper) Subject: Re: Variable-length ladderline tuner: implementation issues Date: Tue, 18 Jun 1996 17:12:37 GMT Message-ID: References: <199606171153.HAA10414@comm1.ab.umd.edu> <4q429t$7qt@nnrp1.news.primenet.com> >Cecil Moore writes: >>Pete Soper wrote: >>: I got no responses to my recent posting about how to design the >>: R/C circuit for damping relay coils as they are de-energized. >Hi Pete, I didn't see your posting. What was the subject? Are you >sure it got posted? What I have done is drive the relay with The subject was something like "making relays quiet" and I didn't wait long as I'm running short of time. I'm not sure of anything to do with my Usenet feed. When I get other's postings, in random time order or any order at all I count myself lucky. You and many others can treat Usenet as a conversational device with a few hours or day delay our thereabouts, while for me it's like the Liberian Postal Service. >double the rated voltage with a resistor in series equal to the >coil resistance and a 0.1 pf cap across the coil. Well that's another combination I wasn't aware of. I'll assume you meant .1uf. So the shunt resistor provides snubbing action? I assume the capacitor looks like a short to RF? >>: My concern is that each time I flip off a relay as I switch the >>: tuner a noise spike will be induced into the nearby ladder line, >I wouldn't recommend switching the relays with RF on them. What I >do is switch the relays without RF on them, then apply RF and write I didn't mean to imply I'd be switching the relays with transmit power applied . I'll never do that intentionally. Say I'm listening to my receiver, hooked via the tuner to an antenna. It's time to change bands or whatever, so I deenergize one of the relays of the tuner to switch the length of ladder line present. As the relay coil's field collapses a back EMF potential of a few hundred volts appears and gets coupled into the ladder line path to my receiver via the coil's ground return line and from there ends up in my eardrums. This is my first concern. The second is that I want to replace the mechanical switches controlling the relays with logic operated devices in the future and I'm sure they won't want to see high potentials coming at them. The last concern was RF flowing through a rectifier (either part of a snubber or an indicator LED). If you say all or part of this is a non-issue, fine, that's exactly what I'm looking for. >I try not to anticipate problems but solve them as they arrise. >Quite often an anticipated problem never occurs. Granted, but trying to figure out what could happen and what I would do about it is part of my personality and the way I learn about things in depth. Different strokes, heh? >I kept the covers, brought the common wires out holes in the covers >and fastened them to the ladder-line outside the relay cover. I found >that trying to solder the ladder-line to the common moving arms >caused the relay electro-mechanical sensitivity to change for the worse. >I used a glue gun to seal the holes. This is a key point and has saved me horrible grief. This would have dawned on me (like a load of bricks) as I was finishing the first solder joint (duh). Limber but well-dressed wires of the right gauge and spacing "coming up". I'll put some more lucite supports in place and run the "relay interconnect" ladder line along one side with breaks adjacent to each relay and tie the limber wires across to each side of each break. This should actually be a great deal cleaner than what I was going to do. And it seems that this kind of interconnect would be better for the loops too, as running the ladder line loops right to the relay's end terminals is looking to be very messy. (In my posting I incorrectly described the loops being on the moving arms, which of course they are not). So if I had it to do over again, I'd cut the moving arm wires at the relay connector and thread them through small holes in the end of the relay's cover, sealing them with a little blob of coax-seal (not glue, which is irreversible) . It looks like I should have started with a U-shaped channel of three rectangular lucite strips cemented together. The middle would hold the relays while the others would run on either side of the row, holding the ladder line connections. Power and ground could come in from below the relays to be at right angles to the ladder line and "limber interconnect" wire pairs. Then the whole thing would be mounted on one side so the short loops could hang down. By direct mail Jay (jay123a@ptw.com) suggested a rectifier diode in parallel with a 1000pf cap across the relay coils, saying this should prevent RF from interacting with the relay. And Brian Olliver () suggested .1uf in series with 33 ohms across the coil as a "snubber". Thanks to all. Regards, Pete KS4XG From amsoft@epix.net Wed Jun 19 21:11:25 1996 From: Jay123a Newsgroups: rec.radio.amateur.homebrew,rec.radio.amateur.antenna To: psoper@encore.com Subject: Re: Variable-length ladderline tuner: implementation issues References: <199606171153.HAA10414@comm1.ab.umd.edu> Message-ID: <31c6c09e.0@205.230.56.7> Date: 18 Jun 96 14:43:42 GMT psoper@encore.com (Pete Soper) wrote: >I got no responses to my recent posting about how to design the >R/C circuit for damping relay coils as they are de-energized. >The Sams' Radio Engineering book rates a series resistor/capacitor >circuit as third in effectiveness after a single diode or back to >back diode pair for controlling high voltage as the relay coil field >collapses. I'm concerned that the diode route might get me into >trouble with nearby RF fields (i.e. as a nonlinear element and >thus potential RFI source), but 'm not savvy enough to chose the R/C >values for my relays (12 volt, 400 ohm coils), thus the posting. > >My concern is that each time I flip off a relay as I switch the >tuner a noise spike will be induced into the nearby ladder line, >attempting to break my eardrums. Perhaps this is a non-issue? >Anyway, I'll go the empirical route and test for receiver "pops" >after wiring up the first relay. > >Pete >KS4XG Hello Pete: Just use a diode across the relay coils to attenuate the relays de-energized reverse voltage pulse, and if you think that local RF will effect the relays just add a 1000 pf disc capacitor across the doide, it really shouldn't be bothered by local RF energy if you have a reasonable SWR. Jay From amsoft@epix.net Wed Jun 19 21:11:26 1996 From: n7ws@azstarnet.com (Wes Stewart) Newsgroups: rec.radio.amateur.antenna Subject: Re: What if I trim the dipole to fit Date: Tue, 18 Jun 1996 21:04:30 LOCAL Message-ID: References: In article hmaxwell@netcom.com (Helene Maxwell ) writes: >From: hmaxwell@netcom.com (Helene Maxwell) >Subject: What if I trim the dipole to fit >Date: Mon, 17 Jun 1996 06:37:51 GMT >I'm setting up a 160-10 meter dipole but was a little too optimistic >about the length from one corner of my little city lot to the other. >The wire is now 134' long and about 14' too long to fit comfortably. >My choices seem to be: >1) Erect a pole on the roof of my house to raise the center into an >inverted V and take up the slack that way. It would be a bend of some 30 >degrees, not 90! >2) snip those 14' right off (along with any hope for 160 meter contacts?). >Can you comment on the pros and cons of either approach? You can also >tell me that 160 meters isn't worth trying to bother with 180 watts >and a dipole, and I'll listen to you. Thanks for any tips. Randy >-- Randy: You don't specify how you anticipate using your dipole as a multiband antenna. Traps, open-wire feed, parallel wires? A 120' wire and some open wire line and tuner would work nearly as well as a resonant length wire. The bandwidth of the wire will be very narrow on 160M anyway, so a tuner is probably in order. Of course, if the pole on the house adds height, this might be useful. I don't quite understand the angles you speak of, so maybe this approach is counter-productive. I haven't been on 160 in a while, but at this time of year, you may not be missing much. I have a dual-band 20-80 meter trapped dipole about 35 ft high in the middle and drooping to about 20'. With extension wires on the end which were about 5' off ground, I have used it on 160 and have worked the Far East and Europe (once) from So. AZ running a KW. 73, Wes -- N7WS From amsoft@epix.net Wed Jun 19 21:11:27 1996 Newsgroups: rec.radio.amateur.antenna From: patrick_tatro@stortek.com (Patrick Tatro) Subject: Re: What if I trim the dipole to fit Message-ID: References: Date: Wed, 19 Jun 1996 13:04:04 GMT In article , hmaxwell@netcom.com (Helene Maxwell) wrote: >Newsgroups: rec.radio.amateur.antenna >Path: stortek!csn!nntp-xfer-2.csn.net!symbios.com!southw ind.net!news.sprintlink.net!news-dc-5.sprintlink.n et!news.sprintlink.net!news-dc-9.sprintlink.net!ta nk.news.pipex.net!pipex!lade.news.pipex.net!pipex! news.be.innet.net!INbe.net!news.nl.innet.net!INnl. net!hunter.premier.net!netnews.worldnet.att.net!ix netcom.com!ixnews1.ix.netcom.com!netcom.com!hmaxw ell >From: hmaxwell@netcom.com (Helene Maxwell) >Subject: What if I trim the dipole to fit >Message-ID: >Organization: NETCOM On-line Communication Services (408 261-4700 guest) >X-Newsreader: TIN [version 1.2 PL1] >Date: Mon, 17 Jun 1996 06:37:51 GMT >Lines: 16 >Sender: hmaxwell@netcom20.netcom.com >Status: N > >I'm setting up a 160-10 meter dipole but was a little too optimistic >about the length from one corner of my little city lot to the other. >The wire is now 134' long and about 14' too long to fit comfortably. >My choices seem to be: > >1) Erect a pole on the roof of my house to raise the center into an >inverted V and take up the slack that way. It would be a bend of some 30 >degrees, not 90! > >2) snip those 14' right off (along with any hope for 160 meter contacts?). > >Can you comment on the pros and cons of either approach? You can also >tell me that 160 meters isn't worth trying to bother with 180 watts >and a dipole, and I'll listen to you. Thanks for any tips. Randy Randy I have an 80-40 dipole on a 40'x90' lot. I asked my neighbors if I could run my dipole over their lot and then I asked their neighbors if I could tie the ends in their trees. It's been working fine now for almost 2 years. I have a snow blower and show my appreciation by clearing their sidewalks in the winter. Good Luck 73's Pat N0WCG From amsoft@epix.net Wed Jun 19 21:11:28 1996 From: pacrimgolf@kuentos.guam.net (Jim Kehler) Newsgroups: rec.radio.amateur.antenna Subject: Re: What's the best height for an R-7 Date: Thu, 13 Jun 1996 05:58:10 GMT Message-ID: <4poe26$hu0@lehi.kuentos.guam.net> References: <4ovt9k$os0@oskgw.osk.sony.co.jp> <4ph7pr$1ki8@ausnews.austin.ibm.com> <4pm8gr$nkm@castle.nando.net> Reply-To: pacrimgolf@kuentos.guam.net K5ESW@nando.net (Paul Ferguson) wrote: >>The manual specifies 8 feet off the ground is best. >My R-7 Manual says the dimensions recommended are based on the R7 >approx. 8 feet above ground and 25 feet from surrounding objects. It >does not say 8 feet is the optimum height. I assume they are saying >the dimensions may change as you tune the antenna for min SWR. >I do not have the answer as to optimum height. Maybe someone has >modeled the antenna? We have not not done any computer modeling or specific analysis with elaborate test equipment, but pratical field testing of the R7 antenna by several hams has here shown the optimum height for the antenna is about one foot above a large trash can, right before you drop it in. 73, Jim KH2D From amsoft@epix.net Wed Jun 19 21:11:31 1996 From: hturn@pelican.davlin.net (Hank Turner) Newsgroups: rec.radio.amateur.antenna Subject: Re: What's the best height for an R-7 Date: Thu, 13 Jun 1996 07:44:10 GMT Message-ID: <31bfc54a.10927678@news.davlin.net> References: <4ovt9k$os0@oskgw.osk.sony.co.jp> <4ph7pr$1ki8@ausnews.austin.ibm.com> Reply-To: hturn@pelican.davlin.net On 10 Jun 1996 13:26:19 GMT, phertler@ (Peter Hertler) wrote: >In <4ovt9k$os0@oskgw.osk.sony.co.jp>, Peter Shintani writes: >>Hi: >> I have an R-7 mounted on the side of my house. The base of the antenna is adjacent >>to the eaves trough. The eaves trough is about 6m above the ground. It seems to work, >>but QRN trash is about s-9 anytime of the day. 40 m performance seems ok, bu t >>20 and 15 m is too quiet, perhaps the antenna is not working well. >> >>I am considering remounting the antenna on to the peak of the roof on top o f a 4m >>mast. Would the additional 4m of height be significant ? >>I know that higher is better for most antenna's but in the case of a vertica l, and >>specifically the halfwave R-7 vertical does the low angle radiation worsen ? >>For example do strange lobes appear when the antenna is raised to far above the ground ? >> >>Peter >> I have an R-5. I needed a antenna that covers many bands, and since I live in one of those subdivisions where the folks hate antennas I picked this one. At first had it mounted at 10', it worked well. I know have it mounted 25'. Only noticible difference is working local 10m. If one just mounts the thing in the clear it will work. KC5FLJ From amsoft@epix.net Wed Jun 19 21:11:32 1996 From: anthonys@ix.netcom.com(Anthony Severdia) Newsgroups: rec.radio.amateur.antenna Subject: Re: What's the best height for an R-7 Date: 13 Jun 1996 07:44:16 GMT Message-ID: <4pogsg$b8e@sjx-ixn2.ix.netcom.com> References: <4ovt9k$os0@oskgw.osk.sony.co.jp> <4ph7pr$1ki8@ausnews.austin.ibm.com> <4pm8gr$nkm@castle.nando.net> <4poe26$hu0@lehi.kuentos.guam.net> In <4poe26$hu0@lehi.kuentos.guam.net> pacrimgolf@kuentos.guam.net (Jim Kehler) writes: (in part): >We have not not done any computer modeling or specific analysis with >elaborate test equipment, but pratical field testing of the R7 antenna >by several hams has here shown the optimum height for the antenna is >about one foot above a large trash can, right before you drop it in. > >73, Jim KH2D > A CLASSIC come-back if I every heard one! Many, many chuckles at this QTH. Thanks. -=Tony=- W6ANV From amsoft@epix.net Wed Jun 19 21:11:33 1996 Newsgroups: rec.radio.amateur.antenna From: webbte Subject: Re: What's the best height for an R-7 Message-ID: Reply-To: ted.webb@columbiasc.ncr.com (webbte) References: <4pm8gr$nkm@castle.nando.net> Date: Thu, 13 Jun 1996 17:11:50 GMT My two cents worth as a very satisfied user of the R-7. I have mine mounted on the chimney at the 2nd story roof line level. It is elevated from the RS chimney mount using a 5 foot piece of chain link fence post. The ground plane clears the top of the chimney by about 4 feet. So my estimate is that the base is about 35' up. It has worked great for the past 2 years, working a lot of 20/40 meter dx, usually from dxpeditions. The SWR readings did change after adjusting for best match at ground level. When mounted, the swr readings gave me diff. resonant feed points, but not enough to risk climbing up and fixing. Had no noticable change in noise level from alternate inverted V when comparing the receive function. ted / ac4cs >==========Paul Ferguson, 6/12/96========== > > >>> >>>I am considering remounting the antenna on to the peak of the >roof on top of a 4m >>>mast. Would the additional 4m of height be significant ? >>>I know that higher is better for most antenna's but in the >case of a vertical, and >>>specifically the halfwave R-7 vertical does the low angle >radiation worsen ? >>>For example do strange lobes appear when the antenna is >raised to far above the ground ? >>> >>>Peter >>> >>> > > >>The manual specifies 8 feet off the ground is best. >> > >My R-7 Manual says the dimensions recommended are based on the R7 >approx. 8 feet above ground and 25 feet from surrounding objects. It >does not say 8 feet is the optimum height. I assume they are saying >the dimensions may change as you tune the antenna for min SWR. > >I do not have the answer as to optimum height. Maybe someone has >modeled the antenna? > >73, > >Paul Ferguson >K5ESW@nando.net > From amsoft@epix.net Wed Jun 19 21:11:34 1996 Newsgroups: rec.radio.amateur.antenna From: n4lq@iglou.com (Steve Ellington) Subject: Re: What's the best height for an R-7 Message-ID: References: <4ovt9k$os0@oskgw.osk.sony.co.jp> <4ph7pr$1ki8@ausnews.austin.ibm.com> <4pm8gr$nkm@castle.nando.net> Date: Wed, 12 Jun 1996 15:50:40 GMT The optimum height varies per band. I got the best results on 40 meters at a height of 5ft but performance on 20 and above was terrible until I raised it to the top of my 60ft tower. Really, the thing is too flimbsey to stick on a tower anyway! This finding agrees with antenna theory. Changing the wavelength of any antenna above ground will affect the angle of radiation. Since each band has different charateristics and you want to work various distances etc. Then there is no such thing as an Optimum height for a multiband antenna. Everything about them is a compromise. I suggest you just stick with the 8ft height. If you decide to put it up heigher, sell it and put an inverted vee on the support fed with tuned feeders. It will outperform the vertical, hands down. : >> : >>I am considering remounting the antenna on to the peak of the roof on top of a 4m : >>mast. Would the additional 4m of height be significant ? : >>I know that higher is better for most antenna's but in the case of a verti cal, and : >>specifically the halfwave R-7 vertical does the low angle radiation worsen ? : >>For example do strange lobes appear when the antenna is raised to far abo ve the ground ? : >> : >>Peter : >> : >> : >The manual specifies 8 feet off the ground is best. : > : My R-7 Manual says the dimensions recommended are based on the R7 : approx. 8 feet above ground and 25 feet from surrounding objects. It : does not say 8 feet is the optimum height. I assume they are saying : the dimensions may change as you tune the antenna for min SWR. : I do not have the answer as to optimum height. Maybe someone has : modeled the antenna? : 73, : Paul Ferguson : K5ESW@nando.net -- Steve Ellington N4LQ@IGLOU.COM Louisville, Ky From amsoft@epix.net Wed Jun 19 21:11:35 1996 From: thompson@atl.mindspring.com (david l. thompson) Newsgroups: rec.radio.amateur.antenna Subject: Re: Wire antennas in salty environment Date: Fri, 14 Jun 1996 20:39:17 GMT Message-ID: <4pslji$1l02@mule1.mindspring.com> References: <4pn1bk$fk@doc.zippo.com> Reply-To: thompson@atl.mindspring.com S.Y.Stroobandt@e-eng.hull.ac.uk wrote: >I've been following the postings on stainless steel antennas and I wonder >if somebody can conclude on which type of wire is best for antennas in >a salty environment. >I used to live in Ostend, Belgium at 50m from the shore, which was >great for low take off angles. >But it also had its disadvantages... > You should give the Fritzel FD-4 a try...its stainless, coated and gives a good account of itself on 80, 40, 20, 17, 12, and 10. You need a tuner for 30 and 15. Dave K4JRB From amsoft@epix.net Wed Jun 19 21:11:35 1996 From: Pam Scott Newsgroups: rec.radio.amateur.antenna Subject: WTB: Butternut HF6V Vertical Date: 13 Jun 1996 12:39:01 -0700 Message-ID: <4ppqol$7q9@doc.zippo.com> If you have one for sale please e-mail me the price and if includes instructions and/or radials. Thanks, Pam. petsits@surf.galacticis.com From amsoft@epix.net Wed Jun 19 21:11:36 1996 From: asperges@innotts.co.uk (Jeremy Boot) Newsgroups: rec.radio.amateur.antenna Subject: WWW Pages Date: Tue, 18 Jun 1996 17:06:22 GMT Message-ID: <31c6ce34.1160341@news.innotts.co.uk> Reply-To: asperges@innotts.co.uk ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The Ham Radio Page - nearly 12,000 visitors to date http://www.innotts.co.uk/~asperges/ Already reviewed by several magazines and review of the SWL pages will appear in the July Edition of RadCom. ~~~~~~~~~~~~~~~~~~~~~~~~~~ If you haven't yet seen it, come and see it now: If you have, see the latest updates: * Extensive variety of subjects; * SWL Pages (including scanners); * Questions and Answers; * Links to all the major ham pages; * The new UK Radio Society; * Friends on the Net Plus: Non-ham subjects including historic Wollaton Park, Burns and his Works in his bicentenary year St George and the Dragon. Thanks to all friend and visitors who have supported the pages since they were launched late 1995 to date. 73 de Jeremy G4NJH June 96 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ From amsoft@epix.net Mon Jun 24 21:12:00 1996 From: jim@jimmimna.demon.co.uk (James Mimna) Newsgroups: rec.radio.amateur.antenna Subject: V.H.F. & U.H.F. RHOMBICS Date: Sat, 15 Jun 1996 12:45:49 GMT Message-ID: <31c2af5a.1862557@news.demon.co.uk> I wonder if there is any designs for an antenna for the VHF or th UHF amatuer bands.Any information on the above would be greatly appreciated. Many thanks in anticipation. Jim@Jimmimna.demon co.uk From amsoft@epix.net Mon Jun 24 21:12:00 1996 From: pmarkham@sun.lssu.EDU (Peter Markham) Newsgroups: rec.radio.amateur.antenna Subject: Tnx, 1/4 wave z xfmr info Date: 21 Jun 96 17:02:54 GMT Message-ID: <199606211703.NAA00411@sun.lssu.edu> Thanks for the many responses, public and private. Pete/wa4hei From amsoft@epix.net Mon Jun 24 21:12:01 1996 From: allshous@pacbell.net Newsgroups: rec.radio.amateur.antenna Subject: Unknown Balun Date: Thu, 20 Jun 1996 18:59:35 -0700 Message-ID: <31CA0207.1A63@pacbell.net> I've come into possession of a "The Big Signal W2AU BALUN and lightning arrestor Model 4-1" made by Unadilla Radioation Products Divison of Microwave Filter Co, Inc, East Syracuse NY. Anybody know of this product/company? Might it be a 4:1 Balun? From amsoft@epix.net Mon Jun 24 21:12:02 1996 From: pflautt@freenet.columbus.oh.us (Paul Flautt) Newsgroups: rec.radio.amateur.antenna Subject: diamond sg-2000 tuning Date: 21 Jun 1996 06:42:37 -0400 Message-ID: <4qduat$rks@acme.freenet.columbus.oh.us> -- pflautt@freenet.columbus.oh.us KB8CMW @ W8CQK.CMH.USA.NOAM KB8CMW @ N8JYV.#CMH.USA.NOAM paul.j.flautt@ameritech.com From amsoft@epix.net Mon Jun 24 21:12:03 1996 From: shaner@postoffice.ptd.net (shane) Newsgroups: rec.radio.amateur.antenna Subject: Wanted: 6-Meter Antenna For SSB Operation Date: 18 Jun 1996 17:04:04 GMT Message-ID: <4q6ni4$ps0@ns2.ptd.net> Wanted: 6-Meter Antenna for Sideband operation. Please e-mail me if you have an antenna you would like to sell. n3wdm@prolog.net 73, Shane Reichenbach From amsoft@epix.net Mon Jun 24 21:12:04 1996 From: decibel7@aol.com (Decibel7) Newsgroups: rec.radio.amateur.antenna Subject: Help! build a loop antenna Date: 21 Jun 1996 20:49:52 -0400 Message-ID: <4qffvg$qjp@newsbf02.news.aol.com> Reply-To: decibel7@aol.com (Decibel7) Greetings, I have heard of a directional antenna that I can use for CB band that is a "loop" antenna. Can anyone tell me how to build this? Good speed to your modem Decibel7 From amsoft@epix.net Mon Jun 24 21:12:05 1996 From: Jeff Hutchinson Newsgroups: rec.radio.amateur.antenna Subject: Phased B-nuts Date: Mon, 17 Jun 1996 15:39:45 -0300 Message-ID: <31C5A671.138B@digital.net> Does anyone have experience with phased Butternut HF6-V vertical antennas? I have installed two of them, spaced 16.5 ft apart (1/4 u @ 14mHZ,) and am using a 3/4 u phasing line between them. My objective is to enhance signal propogation to Europe from my east coastal Florida QTH.I have a bunch of questions that would make sense only to a fellow HF6 user. Any comments? From amsoft@epix.net Mon Jun 24 21:12:05 1996 From: James Prentice Newsgroups: rec.radio.amateur.antenna Subject: Re: screwdriver antenna for sale Date: 18 Jun 1996 01:05:29 GMT Message-ID: <4q4vcp$ejq@mtinsc01-mgt.ops.worldnet.att.net> References: <4pvebu$oml@clark.zippo.com> To: marshall@hilconet.com How much are you asking for ant ? has it been used etc etc.. more details please. tj ant hi sierra etc.. pse send reply to prentice@scanva.canton.edu tks From amsoft@epix.net Mon Jun 24 21:12:06 1996 From: S.Y.Stroobandt@e-eng.hull.ac.uk Newsgroups: rec.radio.amateur.antenna Subject: Buried radials: Insulated or bare? Date: 24 Jun 1996 03:25:29 -0700 Message-ID: <4qlqep$5j6@doc.zippo.com> Hi there, Can anybody tell me what is best: insulated or buried radials? My guess is that the performance level of both should be about the same, except that insulated radials will last longer. 73 de Serge, G/ON4BAA From amsoft@epix.net Mon Jun 24 21:12:08 1996 From: mcfadden@ro.com Newsgroups: rec.radio.amateur.antenna Subject: Help: tranmission lines equations Date: Wed, 19 Jun 96 09:59:49 GMT Message-ID: To anyone out there who might be able to help me out. I am after a reference that will: a) give me the appropriate transmission line equations for a shielded twisted pair line and b) show how these equations are derived. Specifically I'm interested in how the number of turns per unit length affects the equations. I'm an engineer, but electromagnetics is not my area, so I woul d appreciate anyone sending me a reference or giving me some idea of how to get to what I'm after. Thank you. If you wish, you can send a note to my e-mail address: mcfadden@ro.com From amsoft@epix.net Mon Jun 24 21:12:08 1996 From: linville@freenet.edmonton.ab.ca () Newsgroups: rec.radio.amateur.antenna Subject: Re: Butternut HF6V Vertical: Opinions? Date: 24 Jun 1996 18:55:20 GMT Message-ID: <4qmoao$e1e@news.sas.ab.ca> References: <960619204416_138681690@emout12.mail.aol.com> I agree, the Butternut vertical is a strong, well designed atenna. I have mine at ground level with 4 radials. The antenna has been up for 10 years with not a problem. It has withstood many prairie blizzards, two near misses by tornados and still works great. The band width isn't anything special on 80, but with any tuner, the bandedges are workable. Mine went up within 2 hours from box to tuneup. Allen VE6BEQ From amsoft@epix.net Mon Jun 24 21:12:09 1996 From: fsimonds@icanect.net (Terry Simonds) Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.misc Subject: GROUNDING AND LIGHTNING PROTECTION Date: Wed, 19 Jun 96 14:10:51 GMT Message-ID: <4q92l4$nr8@news.icanect.net> Here are two sites that contain quite a lot of good information on grounding and lightning protection. http://www.powerclinic.com/examlist.htm (mostly grounding) http://www.polyphaser.com (grounding and protection. Read the newsletter issues that pertain to ham antenna/station protection) Good stuff--73 Terry/WB4FXD From amsoft@epix.net Mon Jun 24 21:12:10 1996 From: wilson@afn.org (Jim B. Wilson) Newsgroups: rec.radio.amateur.antenna Subject: NEC Ford Broncho? Date: 19 Jun 1996 14:59:55 GMT Message-ID: <4q94lb$ks7@huron.eel.ufl.edu> Keywords: NEC model Broncho I saw it, but now I can't find it to save me. Someone posted the URL or ftp location of a NEC patch or grid model of a Ford Broncho or Explorer (as I recall). Can someone redirect me to this model so I can avoid a tedious measuring job? Jim Wilson WA5BRB From amsoft@epix.net Mon Jun 24 21:12:11 1996 Newsgroups: rec.radio.amateur.antenna From: x Subject: Antenna Design Information, Need Technical Information Message-ID: <31C71400.1505@fgi.net> Date: Tue, 18 Jun 1996 15:39:29 -0500 Reply-To: mmason@fgi.net I am looking for recent technical information on antennas for receiving all frequencies. If you know of any books or other resources that spell out theories of designs and materials please mail me. mmason@fgi.net Thank you, Mark Mason From amsoft@epix.net Mon Jun 24 21:12:12 1996 From: bat@gateway.grumman.com (Pat Masterson) Newsgroups: rec.radio.amateur.antenna Subject: cheap 440 beam ? Date: 21 Jun 1996 11:54:37 -0400 Message-ID: <4qegjt$g28@gateway.grumman.com> I need a cheap, 3 or 4 element beam for 441. It's going to be an indoor antenna, so ruggedness is not necessary. Are there plans anywhere for a simple beam that doesn't need any special feeds or baluns, matches 50 ohms easily? I can use a wooden boom, and 12 guage copper for elements. Thanks. -- * Pat Masterson B38-111, Northrop Grumman Corp.* Ham:KE2LJ * 1111 Stewart Ave., Bethpage NY 11714 * Packet: KE2LJ@KC2FD.NY * 516-346-6316 * President Grumman Amateur * email: bat@grumman.com * Radio Club WA2LQO From amsoft@epix.net Mon Jun 24 21:12:13 1996 From: thompson@atl.mindspring.com (david l. thompson) Newsgroups: rec.radio.amateur.antenna Subject: Re: Magic Raibeam 2 el array Date: Fri, 14 Jun 1996 20:13:43 GMT Message-ID: <4psk3l$2gfa@mule2.mindspring.com> References: <8C24317.02CF0013DB.uuout@cencore.com> Reply-To: thompson@atl.mindspring.com I talked the the ZL listed in their ads. He had a good signal (4el version on 10) but was about 6 to 10DB below ZL2APW and ZL4BO. Reminds me of the W3 two letter guy with a VK call sign too who came to Atlanta several years ago claiming his short boom 3el yagis had 12DBD gain! Guess there is a sucker born every minute.... Dave K4JRB From amsoft@epix.net Mon Jun 24 21:12:14 1996 From: kj4uo@aol.com (KJ4UO) Newsgroups: rec.radio.amateur.antenna Subject: multiband folded dipoles (?) Date: 23 Jun 1996 13:09:57 -0400 Message-ID: <4qjtp5$fiu@newsbf02.news.aol.com> Reply-To: kj4uo@aol.com (KJ4UO) I would like to create a multiband folded dipole by doing the following. Cut it for 30 meters lenght and then short across the folded dipole at the 20m, 17m, 15m, 12m, and 10m locations, thus have a multiband folded dipole. I have never seen this done so I assume that it will not work. Anyone know for sure? Paul KJ4UO P.S. Anyone know Bill Orr's e-mail address? From amsoft@epix.net Mon Jun 24 21:12:15 1996 From: malferman@aol.com (MAlferman) Newsgroups: rec.radio.amateur.antenna Subject: any info on Human Body acting as an antenna? Date: 20 Jun 1996 00:50:42 -0400 Message-ID: <4qalb2$332@newsbf02.news.aol.com> Reply-To: malferman@aol.com (MAlferman) I am looking for any information - research, etc - on how a human body could act as a receiving antenna in the UHF range. This may not actually be Ham Radio related, but I know lots of Hams who have been involved with pretty interesting research. Everyone has seen the effect - touching a TV antenna can improve the signal. Touch your finger to the connector on your HT and you can hear stations. It should be possible for the body to improve reception for a low-power wireless application. Any ideas? From amsoft@epix.net Mon Jun 24 21:12:16 1996 From: Maude Schyffert Newsgroups: rec.radio.amateur.antenna Subject: Re: 916 mhz yagi design ....help please Date: Thu, 20 Jun 1996 14:22:43 -0700 Message-ID: <31C9C123.77E1@mailbox.swipnet.se> References: <4q769j$juo@makai.maui.net> Reply-To: maude.schyffert@mailbox.swipnet.se MS wrote: > > Looking for a simple and inexpensive 916 mhz. yagi design. Possibly a > 6 or 10 element. I have a design for 902-903mhz, but I don't know how > to modify specs for higher freq. I know basically nothing, so please > include where coax is hooked to driven element. Is shield also > attached? I am trying to increase range of video reception, and is > there any type of inexpensive signal booster available? All info will > be greatly appreciated. > Thanks so much. Michael Use the design you have for 916, it is only 2 per cent off.... SM0BKZ From amsoft@epix.net Mon Jun 24 21:12:16 1996 From: hamop@aztec.asu.edu (CHARLES J. MICHAELS) Newsgroups: rec.radio.amateur.antenna Subject: Re: Ladder line variability questions Date: 22 Jun 1996 04:16:14 GMT Message-ID: <4qfs2e$fka@news.asu.edu> Pete said about ladder line - I'd thought about it, but dismissed it. So this is the missing factor? Ladder line with thicker conductors have different insulation characteristics to get the impedance back to the target? No, Pete; The insulation is to hold the line together , the conductor diameter is then selected to provide the specific impedance in the environment of the insulation. Charlie, W7XC -- From amsoft@epix.net Mon Jun 24 21:12:18 1996 From: Cecil Moore Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Hopeless to run HF voice at 100 watts? Date: 18 Jun 1996 13:48:29 GMT Message-ID: <4q6c3e$qih@itnews.sc.intel.com> References: charles1@netcom.com (charles copeland) wrote: > and a 64 foot folded dipole at 7' in my first floor apartment > My luck has been rotten, Hi Charles, this is not luck. This is a system designed to fail. The percentage of energy not making it up out of your house has to be in the 90s, probably in the high 90s. By all means get that antenna up to 40 ft or higher. I regularly talk to New Zealand on 100w and a 102 ft dipole at 30 ft. 73, Cecil, KG7BK, OOTC (not speaking for my employer) From amsoft@epix.net Mon Jun 24 21:12:19 1996 Newsgroups: rec.radio.amateur.antenna From: bart@wb6hqk.ampr.org (Bart Rowlett) Subject: Re: black twin-lead phone line; How many Ohms? Message-ID: References: <6c7cc$1622f.206@news.linknet.net> Date: Thu, 20 Jun 1996 02:29:57 GMT In article <6c7cc$1622f.206@news.linknet.net>, Russ wrote: > >Does anyone know anything about using the black 2-wire out-door >telephone line as a feed line? Wonder what the feedline impedance on >this stuff would be? At any rate, it looks like it would make good >dipole and longwire stock. Anyone used this stuff before? > It depends on the actual insulation material. Some of it is polyethelene insulation over copperweld conductors with reasonable loss at HF. Others are very lossy at 7 MHz, apparently due to the material added to inhibit UV deterioration. Some is some sort of rubber and is several dB per half wavelength at 7 MHz. Zo tends to be about 175 - 250 ohms. bart wb6hqk From amsoft@epix.net Mon Jun 24 21:12:20 1996 From: pip@shore.net (GeorgeS) Newsgroups: rec.radio.amateur.antenna Subject: Re: Looking for surplus microwave reciver, for radio astronomy Date: 19 Jun 1996 14:50:42 GMT Message-ID: <4q9442$i3i@shore.shore.net> References: In article , stargazr@mindspring.com says... > >I am building a radio telescope on a shoestring. I have a dish and converter >and motor. I don't need or want anything new or fancy. All I need to do is >to measure signal strength. Feed that to a A/D and keep track of 24 hours a >day on my p.c. You could use an LNB that the tvro people use C 4 GHz Ku 12 GHz The noise tempereature of the LNB is about 17 - 20 degrees Kelvin. See http://www.nmia.com/~roberts/robert.html for references to vendors From amsoft@epix.net Mon Jun 24 21:12:20 1996 From: w7el@teleport.com (Roy Lewallen) Newsgroups: rec.radio.amateur.antenna Subject: Re: Help in modelling this antenna Date: Thu, 20 Jun 96 07:47:05 GMT Message-ID: <4qavm5$c9u@nadine.teleport.com> References: <4q9s6h$8ug@news.asu.edu> In article <4q9s6h$8ug@news.asu.edu>, hamop@aztec.asu.edu (CHARLES J. MICHAELS) wrote: >. . . >I assumed 300 ohm line was tubular transmitting type and antenna >of #12 wire at height of about 30 feet since seems unlikely that line >is perfectly straight down and had to select a frequency in each >band. > >. . . Charlie also made another assumption he didn't mention: that the currents on the feedline are balanced, that is, equal and opposite. This can be hard to accomplish. If it isn't true, the feedline becomes part of the antenna and the impedances can be quite different. Roy Lewallen, W7EL From amsoft@epix.net Mon Jun 24 21:12:22 1996 From: Will Flor Newsgroups: rec.radio.amateur.antenna Subject: Re: Directional Antenna- help please Date: Wed, 19 Jun 1996 11:51:16 -0500 Message-ID: <31C83004.763A@rrgroup.com> References: <4q8jk8$62f@newsbf02.news.aol.com> Decibel7 wrote: > > Greetings, > > How can I build an antenna that is directional as far as Recieving is > concerned?, > > Good speed to your modem > Decibel7 Any of the "standard" directional antennas like yagis, quads, etc. are directional in both receive and transmit; there are lots of plans available in the ARRL handbook, etc. and lots of other publications available from ARRL and many other places. 73 de KB9JTT From amsoft@epix.net Mon Jun 24 21:12:22 1996 From: Gareth Crispell Newsgroups: rec.radio.amateur.antenna Subject: Is a Balun Necessary? Date: 21 Jun 1996 02:02:32 GMT Message-ID: <4qcvro$f3j@alterdial.UU.NET> I am going to put up a yagi monobander and am wondering if a 1:1 is at all necessary? Any and all opinions will be appreciated. -- Gareth Crispell /\ /\ * / / / N1MSV / \/ \/\ -----/\------ stranger@ccsnet.com /\ \ \ \ / / || / N1MSV@KC1KM / \ \ \ \ || 10X International || # 63961 ... and in the time of their visitation they shall shine, and run to and fro like sparks among the stubble. From amsoft@epix.net Mon Jun 24 21:12:23 1996 From: Date: Fri, 21 Jun 96 07:48:52 -0500 Newsgroups: rec.radio.amateur.antenna Subject: Re: 6m antenna Message-ID: > In article <4p709v$11s@omnifest.uwm.edu>, ------------clip-------------- > Do the packet DX clusters also report 6 meter (and other VHF) band openings? > Yes ! Hugh Duff VA3TO Toronto --- ţ NFX v1.3 [000] From amsoft@epix.net Mon Jun 24 21:12:24 1996 From: USCG TELECOMMS Newsgroups: rec.radio.amateur.antenna Subject: Re: HAARP info requested Date: Mon, 24 Jun 1996 08:09:14 -0400 Message-ID: References: <4q6th0$9rn@newsbf02.news.aol.com> <4qgrlv$ctt@newsbf02.news.aol.com> To: W8JI Tom When HAARP was proposed a couple of years ago, I objected to it on behalf of the US Coast Guard. Three sites were originally proposed, one in Texas, one in California and one in Alaska. After meeting with Air Force officials and its contractor, they convinced us our circuits would not be impacted by this. Subsequently, they dropped the proposed California site. I believe they did same with the Texas site. The Alaskan hams and other communicators have been battling the Alaskan HAARP operation via their politial representatives, but have not had much success to date. What appeared to be disruption in communications by HAARP in the intial stages of the game has turned into more of an environmental impact issue. From our meetings with the HAARP proponents, bombarding the ionosphere with such huge amounts of power does cause disruption, but the ionosphere quickly goes back to normal after the power is cut off. W4VR From amsoft@epix.net Mon Jun 24 21:12:25 1996 From: rmd@ka4ybr.netmha.com (Bob Duckworth) Newsgroups: rec.radio.amateur.homebrew,rec.radio.amateur.antenna Subject: Re: Variable-length ladderline tuner: implementation issues Date: 20 Jun 1996 08:42:32 -0400 Message-ID: <4qbgvo$qvu@ka4ybr.netmha.com> References: <199606171153.HAA10414@comm1.ab.umd.edu> <31c6c09e.0@205.230.56.7> Has anyone considered using stepping relays for switching the line segments? 4 x SPNT (N=# of segments + 1 for indexing) A microcontroller could step until the index is found and then step to the appropriate segment based on your lookup table. Heck, you could generate a signal to crank the RF down while stepping. If anyone knows of some suitable relays..... -bob -- Bob Duckworth Consulting, 960 Ralph McGill Blvd. Atlanta GA 30306-4447 bobs' address is rmd@ka4ybr.netmha.com 404-888-0389(V) 892-2301(FAX) Buy Sell Trade Surplus Computer Electronics Datacom Telecom since 1981. Fax or email your list for a fast cash offer. Watch for listserv catalog. From amsoft@epix.net Mon Jun 24 21:12:26 1996 From: "Earl Needham" Newsgroups: rec.radio.amateur.antenna Subject: Homebuilt mobile 6 meter / 2 meter antenna? Date: Fri, 21 Jun 1996 17:57:01 -0600 Message-ID: <01bb5fcd.56bd46c0$f31865ce@SNeedha.3lefties.com> I'm interested in a combination 6 meter and 2 meter mobile antenna. However, at the price for commercially available gear, I'd end up spending about $80 US for the antenna, $70 US for the mount, and probably $80 US for the duplexer. Has anyone ever homebuilt an antenna for these two bands, perhaps using a trap? If so, would you mind giving me some pointers / ideas for doing so? Thanks! -- Earl Needham, KD5XB, in Clovis, NM Phi Mu Alpha Sinfonia, Pi Chi '76 Have you really jumped ROUND PARACHUTES? (Overheard at the Clovis Parachute Center) From amsoft@epix.net Mon Jun 24 21:12:27 1996 From: gfoley@freenet.columbus.oh.us (Gerard Foley) Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Hopeless to run HF voice at 100 watts? Date: 20 Jun 1996 13:50:29 -0400 Message-ID: <4qc315$6l5@acme.freenet.columbus.oh.us> References: <31C618E5.3567@ix.netcom.com> charles copeland (charles1@netcom.com) wrote: : Yes, I've gotten a tremendous amount of e-mail (30!) on this and all agree : that 100 watts is sufficient. All replies have focused on my antenna ... : or lack of an adequate antenna. : Thanks to all who replied! Its good to know that is hope at 100 watts. In case noone else has mentioned it, DO NOT ATTEMPT TO IMPROVE YOUR RESULTS BY GETTING AN AMPLIFIER!. Putting 100 Watts into the antenna you describe is risky enough. More power might endanger your health, or start a fire somewhere that you won't see it for a while. K8EF -- Gerry From amsoft@epix.net Mon Jun 24 21:12:28 1996 From: glenne@sr.hp.com (Glenn Elmore) Newsgroups: rec.radio.amateur.antenna Subject: Re: 916 mhz yagi design ....help please Date: 20 Jun 1996 18:52:31 GMT Message-ID: <4qc6lf$fnn@canyon.sr.hp.com> References: <4q769j$juo@makai.maui.net> MS (bestmaui@maui.net) wrote: : Looking for a simple and inexpensive 916 mhz. yagi design. Possibly a : 6 or 10 element. I have a design for 902-903mhz, but I don't know how : to modify specs for higher freq. I know basically nothing, so please You might be interested in the design on the web page listed below under "Antenna Designs". Glenn Elmore n6gn amateur IP: glenn@SantaRosa.ampr.org Internet: glenne@sr.hp.com |--------------- N6GN's Higher Speed Packet WWW Page -------------------| | | | http://www.tapr.org/~n6gn/index.html | | | |-----------------------------------------------------------------------| From amsoft@epix.net Mon Jun 24 21:12:29 1996 Newsgroups: rec.radio.amateur.antenna From: n4lq@iglou.com (Steve Ellington) Subject: Re: multiband folded dipoles (?) Message-ID: References: <4qjtp5$fiu@newsbf02.news.aol.com> Date: Sun, 23 Jun 1996 19:21:18 GMT You are quite correct Paul. KJ4UO (kj4uo@aol.com) wrote: : I would like to create a multiband folded dipole by doing the following. : Cut it for 30 meters lenght and then short across the folded dipole at the : 20m, 17m, 15m, 12m, and 10m locations, thus have a multiband folded : dipole. I have never seen this done so I assume that it will not work. : Anyone know for sure? : Paul : KJ4UO : P.S. Anyone know Bill Orr's e-mail address? -- Steve Ellington N4LQ@IGLOU.COM Louisville, Ky From amsoft@epix.net Mon Jun 24 21:12:30 1996 From: fsimonds@icanect.net (Terry Simonds) Newsgroups: rec.radio.amateur.antenna Subject: Re: Exceptional grounding for an antenna, does it work? Date: Wed, 19 Jun 96 14:10:39 GMT Message-ID: <4q92kp$nr8@news.icanect.net> References: In article , stargazr@mindspring.com (Robert Miller) wrote: >When I had a C.B. radio years ago I dug a hole were I put my grounding rod. >I layered charcoal and rock salt does this do anything I did it as I >installed my antenna so I couldn't notice better gain. >What effect does this have in transmissions or reciveing? > Robert--You don't say what type of antenna you are using (or want to use). Connecting an antenna to a grounding rod is not a very good idea! Perhaps grounding the antenna-support structure is a prudent move (particularly here in Southeast Florida--the lightning capital of the world). But, this will have very little, if any, effect on antenna performance. Ground rods do an admirable job of trying to keep "free electricity" out of the shack, but I doubt you will notice any difference at all in your received and/or transmitted signal. gl 73--Terry/WB4FXD From amsoft@epix.net Mon Jun 24 21:12:31 1996 From: nts@nortech.com (Dean Heinen) Newsgroups: rec.radio.amateur.misc,rec.radio.amateur.antenna Subject: Re: Belden 9913 Connector Source?? Date: Wed, 19 Jun 1996 08:16:49 LOCAL Message-ID: References: <4q12ko$jhc@news.icanect.net> <4q52gk$60j@dilbert.whoi.edu> In article <4q52gk$60j@dilbert.whoi.edu> jvaldes@whoi.edu writes: >From: jvaldes@whoi.edu >Subject: Re: Belden 9913 Connector Source?? >Date: 18 Jun 1996 01:58:44 GMT >Terry... take a look at 9914, I've not had good luck with 9913 here on >the Cape. The spiral wound center conductor tends to "suck up" moisture >then it gets cold and the water condenses in the cable. I've had water >run out of the coax connectors. 9914 uses a foam core, it's a little more >lossey than the 9913 but it stays dry!!! >Jim Then you are most certainly installing it incorrectly. Dean N7ZRS From amsoft@epix.net Mon Jun 24 21:12:32 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: DDRR antenna -reply to comments Date: 22 Jun 1996 11:08:54 -0400 Message-ID: <4qh2a6$fic@newsbf02.news.aol.com> References: <4qbio5$vkp@ganesh.mc.ti.com> Hi Jim, In article <4qbio5$vkp@ganesh.mc.ti.com>, jafl@msg.ti.com (Jim Flanders) writes: >Yes - The baulb lit on only the horizontal sections - The vertical >section is like this: > > /----- > | ^ > | feed (5.5" from vert. section) > ground So are you saying the bulb lights anywhere along the top ring, but no where on the vertical section? Does it light evenly along the whole ring? 73 Tom From amsoft@epix.net Mon Jun 24 21:12:33 1996 From: kebsch@pdb.sni.de (Kebsch) Newsgroups: rec.radio.amateur.antenna Subject: Re: What's the best height for an R-7 Date: 21 Jun 1996 07:06:07 GMT Message-ID: <4qdhkv$13q@nervous.pdb.sni.de> References: <4pm8gr$nkm@castle.nando.net> Reply-To: Waldemar Kebsch In webbte writes: > ... > ... When mounted, the swr readings gave me diff. resonant > feed points, but not enough to risk climbing up and fixing. > .... Sorry Ted, the frequency, where you find the best (lowest) VSWR is the frequency where your antenna has a radiation resistance close to 50 Ohms, which is the output impedance of your tranceiver and the wave resistance of your feeding coax cable, usually. But in allmost all cases it is *not* the resonance frequency from your antenna. Sorry for my English, but I hope I could make is clear enough ..? 73 de Waldemar, DK3VN -- E-Mail: wkebsch.pad@sni.de .. or .. Packet Radio: DK3VN @ DB0NOS.#NRW.DEU.EU Big antennas, high in the sky, are better than small ones, low! [adh] From amsoft@epix.net Mon Jun 24 21:12:34 1996 From: hamop@aztec.asu.edu (CHARLES J. MICHAELS) Newsgroups: rec.radio.amateur.antenna Subject: Re: Help in modelling this antenna Date: 19 Jun 1996 21:41:37 GMT Message-ID: <4q9s6h$8ug@news.asu.edu> Peter, G4BVH Wanted input impedance to 40 foot 300 ohm line feeding center of 260 foot antenna over average earth on 160, 80, 40, 20,15 and 10 meter bands. I assumed 300 ohm line was tubular transmitting type and antenna of #12 wire at height of about 30 feet since seems unlikely that line is perfectly straight down and had to select a frequency in each band. Band Freq (MHz) Z at antenna Z at input to line 160 1.85 52.409 + j 18.846 86.07 + j 219.14 80 3.8 6114 - j 4804.2 12.36 - j 103.85 40 7.1 1584 + j 2176.1 34.86 + j 206.13 20 14.2 445.28 + j882.15 52.02 - j 140.15 15 21.2 199.45 + j 382.82 1059.12 + j 392.82 10 28.5 191.3 + j 193.32 146.22 + j 98.32 Charlie, W7XC -- From amsoft@epix.net Mon Jun 24 21:12:35 1996 From: hamop@aztec.asu.edu (CHARLES J. MICHAELS) Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line Date: 24 Jun 1996 07:16:16 GMT Message-ID: <4qlfc0$5ep@news.asu.edu> Stan said - Charlie you are exactly right. What is needed is "link coupling". It is nothing more than a transformer. I do disagree on your statement, "It is even worse if the transmitter end of the line is fed from a balun with a grounded center tap. Then the grounded center tap is connected to ground....". No it's not. The grounded center tap is ground to DC but not to RF. Stan, If it is grounded, it's grounded! And if it is grounded, and the antenna end is grounded , then - 1. the end of the balun connected to the side of the line which is grounded at the antenna has the earth loss of whaterver current flows between the two grouded points. 2. With one side of a "balanced" (it won't be balanced anylonger) is connected to ground we no longer can even estimate its impedance. 3. Ther3 is also the problem of how to keep this line out orf the local induction field and radiated field of the antenna. Charlie, W7XC -- From amsoft@epix.net Mon Jun 24 21:12:35 1996 From: crs1026@inforamp.net (Paul Cordingley) Newsgroups: rec.radio.amateur.antenna Subject: Need help with 2-meter mobile suggestions Date: Sat, 22 Jun 1996 15:36:18 GMT Message-ID: <4qh7b1$av@news.inforamp.net> I'm looking for ideas for a quickly-detachable, easy-to-carry mobile antenna for 2 meters. My two constraints: - it must be a quick-on, quick-off affair, no permanent attachment - no magnets I drive a lot in my job, but always in company or rented vehicles, seldom the same vehicle two days in a row. I need something compact I can throw in my bag, with my handleld. I haul around a laptop and lots of floppy disks - hence the no-magnet constraint. I was thinking of fashioning a clamp out of sturdy plastic to fit over the top of a window or door. I'd attach a homemade quarter-wave vertical. The problem I came to was, what about the ground plane? I could add a couple of horizontal elements, which would fit flat against the window , the problem is they'd be coupled to the car body but not directly connected. Any suggestions would be appreciated. 73 Paul VA3MLW From amsoft@epix.net Mon Jun 24 21:12:36 1996 From: Burt Fisher Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: They do not come any phoneyer Date: Sun, 23 Jun 1996 17:29:19 -0400 Message-ID: <31CDB72F.2D72@ccsnet.com> References: <31C618E5.3567@ix.netcom.com> <1996Jun20.133842.10513@ke4zv.atl.ga.us> <31CBCD4B.751C@ccsnet.com> <4qgvrf$5cc@lehi.kuentos.guam.net> Jim Kehler wrote: > Come back and tell us when YOU are dying Burt, that's > something we'd all like to hear. > > 73, Jim KH2D So typical of a phoney ham, wish someone death and best regards in the same message. You speak for all? What is dying is hihi ham radio. #================#=====================================================# | Burt Fisher | Teacher of video, broadcasting and electronics | | Amateur call | South Dennis, Ma. (Cape Cod) | | K1OIK | The less you say, the more people will remember | #================#=====================================================# | k1oik@ccsnet.com | #======================================================================# http://www.qrz.com/cgi-bin/qrz_gifs?k1oik.gif From amsoft@epix.net Mon Jun 24 21:12:37 1996 Newsgroups: rec.radio.amateur.antenna From: kingbp@ka1fqt.mv.com (Bryan King) Subject: HF multiband sloper Message-ID: Date: Mon, 24 Jun 1996 03:44:06 GMT I recently bought an Alpha-Delta DX-B 1/4 wave sloper that covers 160 - 30 meters. I've been having alot of trouble getting it to perform satisfactorily on all of the bands, except for 30 meters. I currently have this antenna fed by a 120' run of RG8-X. The feedpoint is at the top of a 30' aluminum mast and I've attached an aluminum ground wire to it that acts as counterpoise. This is grounded from the feedpoint to a 4' ground rod at the base of the mast. I have very high swr with this particular antenna and thus use an antenna tuner to match the xcvr to the antenna system. On 160, I cannot tune up properly, unless I attach a capcitance hat at the end of the antenna closest to the ground. That is approximately 10' off the ground. The guy wires for the mast are dacron rope. There is a 6 meter vertical on top of the mast. To date this is perhaps the best configuration of the antenna. I've run out of ideas on how to get this antenna to perform properly. Any ideas from the ham community would be greatly appreciated! Thanks & 73, Bryan From amsoft@epix.net Mon Jun 24 21:12:39 1996 From: cphillips@interpath.com (Curt Phillips) Newsgroups: rec.radio.amateur.antenna Subject: Re: Spider antenna Date: Fri, 21 Jun 96 16:11:31 GMT Message-ID: <4qeh8u$hjl@news.interpath.net> References: <4pjk39$9jj@news.fwi.com> In article , Bill Starkgraf wrote: [snip] >I wonder how that happened. I attach the coax to the downspout >and the ground side to the air conditioner copper tubing. From the >LA area I get out well 599 to Northern California. The mesh in the >stucco of my building prevents me from transmitting to the east. [snip] >part. This now allows me to go way up into the state of Washington. >Still the mesh in the building make this one very directional also. >Now how do I place my apartment building on a rotor so that I >can turn it? Better yet, maybe I should find a place to live that Hey, you're in California dude! Just tell'em you want to rotate the building so your solar cells will work better and help the environment. :-) ============ Opinions expressed are solely those of the author ============ Curt Phillips KD4YU (ex-WB4LHI) | Motto of the Chairman, Tarheel Scanner/SWL Grp | Tarheel Scanner/SWL Group: ARRL Life; QCWA; Raleigh ARS; NRA | #2) The more they don't want you to Energy/Recycling BBS 704-547-3114 | listen, the more interesting it must be. ==== cphillips@interpath.com === [Copyright 1996 All rights reserved]====== From amsoft@epix.net Mon Jun 24 21:12:40 1996 From: Jake Brodsky Newsgroups: rec.radio.amateur.antenna Subject: Re: Toroidal Helical Antenna --- Revolutionary New Antenna Date: Thu, 20 Jun 1996 10:35:20 -0700 Message-ID: <31C98BD8.3533@erols.com> References: <31C4476F.4AB2@netaxs.com> <4q712o$b9a@newsbf02.news.aol.com> <4qa0q9$i3o@nadine.teleport.com> Roy Lewallen wrote: > [lots of good criticism and claim debunking] > In general, the claims were pretty vague (although you admittedly can't get > much detail into six paragraphs), and some seem mutually exclusive. The > announcement sounds pretty preliminary, with lots of "could be", "it is > anticipated that", "is possible" type qualifiers. It sounds like an > innovative antenna design with potential advantages in some applications, > but not magic. Roy I think the web page was written by someone who had little or no idea of what s/he was writing about. If this was indeed written by the antenna developers, I'd dismiss the whole thing as just another load of balderdash. Stating antenna gain in percent seems too much like salesmanship. The impression I got was that they have made a helically wound loop antenna. I don't see how it could outperform anything. And the claims about being smaller so that it wouldn't be as much of a problem for low-flying aircraft was a bit too much. Jake Brodsky, AB3A "Beware of the massive impossible!" From amsoft@epix.net Mon Jun 24 21:12:41 1996 From: rmd@ka4ybr.netmha.com (Bob Duckworth) Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Hopeless to run HF voice at 100 watts? Date: 19 Jun 1996 10:53:43 -0400 Message-ID: <4q949n$l3t@ka4ybr.netmha.com> References: <31C64BB7.D06@ix.netcom.com> <31C78A22.690B@netvision.net.il> My advice for what it's worth. Listen a lot. If the signal your receiving is strong then they should be able to hear you even with an inefficient antenna at your end. Listen a lot and learn what band is open when. Sunspot low now so 40m will be dead sometimes. Try CW on 40m. Think about better antennas. I've worked into North Africa from the South Pacific on 75 phone with a measured 30Watts PEP output. THis is halfway around the world. It's all in the antenna. -bob -- Bob Duckworth Consulting, 960 Ralph McGill Blvd. Atlanta GA 30306-4447 bobs' address is rmd@ka4ybr.netmha.com 404-888-0389(V) 892-2301(FAX) Buy Sell Trade Surplus Computer Electronics Datacom Telecom since 1981. Fax or email your list for a fast cash offer. Watch for listserv catalog. From amsoft@epix.net Mon Jun 24 21:12:42 1996 From: kevin@mailbag.com (Kevin Shea) Newsgroups: rec.radio.amateur.antenna Subject: ?Measuring Axial Ratio? Date: Sat, 15 Jun 96 14:43:00 GMT Message-ID: <4pui8u$rks@grandcanyon.binc.net> In an attempt to build a circular polarized antenna (a 1.7 GHz axial mode backfire helical antenna to feed a parabolic reflector ( a 1 meter dish)) it would be great if I could measure the cicularity i.e. the axial ratio of the antenna. I haven't found any "how to" references. I've heard that one can do it with a network analyser. I don't have access to one. but I do have access to signal generator, a sweeper and a spectrum analyser. Any ideas or pointers would be greatly appreciated. BTW the antenna is for receiving RHCP signals from polar orbiting weather satellites. Kevin N9JKP . **************************************** * Kevin G. Shea N9JKP * * 4460 Dahmen Pass * * Cross Plains, WI 53528 USA * * 608.789.4326,voice; 608.798.1747,fax * **************************************** From amsoft@epix.net Mon Jun 24 21:12:43 1996 Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc From: gary@ke4zv.atl.ga.us (Gary Coffman) Subject: Re: Hopeless to run HF voice at 100 watts? Message-ID: <1996Jun20.133842.10513@ke4zv.atl.ga.us> Reply-To: gary@ke4zv.atl.ga.us (Gary Coffman) References: <31C618E5.3567@ix.netcom.com> Date: Thu, 20 Jun 1996 13:38:42 GMT In article charles1@netcom.com (charles copela nd) writes: > >Thanks to all who replied! Its good to know that is hope at 100 watts. > >I'll have to work in this, as it is quit hard being on the first floor >and surrounded by neighbors on all sides and above. When my lease is >up, I'll have to do some serious prospecting on a more suitable apartment. As Carlton Sheets would say, "Why pay the other fellow's mortgage?" Forget apartments, buy a house. It has tax advantages, it builds equity, and if you work the deal right you can put cash in your pocket at the closing. But most important from an amateur point of view, you can put up good antennas. If you're really slick, you'll buy an apartment building. Then you can put up whatever antennas you want, and your other tenants pay the mortgage. In fact, talk to the owner of your current apartment building. You might not even have to move. Gary -- Gary Coffman KE4ZV | You make it, | Due to provider problems Destructive Testing Systems | we break it. | with previous uucp address es 534 Shannon Way | Guaranteed! | Email to ke4zv@radio.org Lawrenceville, GA 30244 | | From amsoft@epix.net Mon Jun 24 21:12:45 1996 From: cphillips@interpath.com (Curt Phillips) Newsgroups: rec.radio.amateur.antenna Subject: Re: Ladder Line Quick-Disconnect Date: Fri, 21 Jun 96 16:01:24 GMT Message-ID: <4qeglv$hjl@news.interpath.net> References: <4pah1t$sl0@crash.microserve.net> <4phstp$qp5@sjx-ixn4.ix.netcom.com> In article <4phstp$qp5@sjx-ixn4.ix.netcom.com>, gsparks@ix.netcom.com(Glenn Sparks) wrote: >I use a ceramic and copper double throw, double pole knife switch that >I found in my grandmothers basement. It is heavy stuff with the blades >about 2 1/2" apart, and the knife portion about 3" long. Believe it or >not she was using it for the basement light. I have the other throw >connected to my ground. Though no doubt not as nice as the switch you got from your grandmother, Radio Shack sells a knife switch which works well enough for my purposes. >I recently was in a customers office and he had a double throw six pole >knife switch, where the knife portion rotated to each of the poles, >anyone else ever seen one of these, looked like a great antenna select >switch for multiple ladder line, but I couldn't talk him out of it. That DOES sound interesting... do you know what this type of switch was originally used for? ========== Opinions expressed are solely those of the author ========= Curt Phillips, CEM KD4YU (ex-WB4LHI) | Motto of the Chairman, Tarheel Scanner/SWL Group | Tarheel Scanner/SWL Group: ARRL Life; QCWA; Raleigh ARS; NRA; AEE| #1) If it's expensive and Energy/Recycling BBS 704-547-3114 | electronic, we like it. == cphillips@interpath.com === [Copyright 1996 All rights reserved]=== From amsoft@epix.net Mon Jun 24 21:12:46 1996 From: moritz@ipers1.e-technik.uni-stuttgart.de () Newsgroups: rec.radio.amateur.antenna Subject: Re: Toroidal Helical Antenna --- Revolutionary New Antenna Date: 20 Jun 1996 16:47:07 GMT Message-ID: <4qbvab$1im4@info4.rus.uni-stuttgart.de> References: <31C4476F.4AB2@netaxs.com> <4q712o$b9a@newsbf02.news.aol.com> <4qa0q9$i3o@nadine.teleport.com> <31C98BD8.3533@erols.com> >Roy I think the web page was written by someone who had little or no >idea of what s/he was writing about. Indeed it looks like written by someone trying to explain the advantages to some one with no knowledge about antennas. But that's policy. I think the concept can ba challenged on simple grounds: Why should the antenna have a high radiation resistance? Although full wave, it is just a magnetic loop. (Think about the combined merits of a rubber duck and an Isoloop). 73, Moritz DL5UH If this was indeed written by >the antenna developers, I'd dismiss the whole thing as just another >load of balderdash. Stating antenna gain in percent seems too much >like salesmanship. > >The impression I got was that they have made a helically wound loop >antenna. I don't see how it could outperform anything. > >And the claims about being smaller so that it wouldn't be as much of >a problem for low-flying aircraft was a bit too much. > >Jake Brodsky, AB3A >"Beware of the massive impossible!" From amsoft@epix.net Mon Jun 24 21:12:47 1996 From: pef@sni.dk (Peter Frenning) Newsgroups: rec.radio.amateur.antenna Subject: Re: Multiband-dipole HELP needed! Date: Mon, 24 Jun 1996 12:43:31 GMT Message-ID: <4qm2hj$bgb@news.dknet.dk> References: <4qjcvr$6f9@perjantai.hit.fi> Reply-To: pef@sni.dk mjappine@news.hit.fi (Mika Antero Jäppinen) wrote: >Hi, > I am looking for multiband dipole antenna for HF which would > cover 80-40-20-15-10 meter bands. > Biggest promblem is that I had to hang it over metal-roof approx > 6-7 feet high from it and this is same as put it inna ground level.. > > So is there any antennas (dipole-horixzontal no yagis) which might > perform atleast well on these kind of circumtanses? > I guess I had to go and buy vertical 8( You lucky bastard you - you actually have the perfect ground-plane for erecting a multitude of verticals! Us poor suckers have to try to string spools and spool of wire to get something useful. /peter ****************************** OZ1PIF ************************** Peter Frenning, UNIX Product Mgr., Siemens-Nixdorf DK, Ph.: +45 4477 4924 Snailmail: Dybendalsvaenget 3, 2630 Taastrup, Denmark, Fax: +45 4477 4977 Email: pef@sni.dk(...!dkuug!sni.dk!pef)(NERV: pfrenning.cph) X400:C=DK; A=400NET; P=SCN; O=SNI; S=Frenning; G=Peter; OU1=CPH1; OU2=CC Private connection: Peter_Frenning@online.pol.dk ****** Come visit us on the web; URL http://www.sni.dk ****** From amsoft@epix.net Mon Jun 24 21:12:48 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: NEWBIE: impedance of 2m 5/8 wave ground plane Date: 24 Jun 1996 09:52:24 -0400 Message-ID: <4qm6io$av8@newsbf02.news.aol.com> References: <4qm5bl$an0@newsbf02.news.aol.com> In article <4qm5bl$an0@newsbf02.news.aol.com>, kenmccoy@aol.com (Ken McCoy) writes: > >Forgive me if this question has an obvious answer; I haven't been able to >find it anywhere. Is the angle of the ground plane segments for a 5/8 wave >vertical the same as that for a 1/4 wave for 50 ohms (i.e., 45 degrees). > >Or, what is the impedance for a 90 degree angle? > >Thanks and 73, >Ken KF4BQF Hi Ken, The 5/8 wl antenna requires a very large flat groundplane in order to have gain over a smaller antenna (like a 1/2 wl antenna). If the groundplane is less than several wl long in each direction, the antenna won't have the gain most people claim. If the groundplane is angled down, a 5/8 wl antenna can actually have less gain along the horizion than a 1/4 or 1/2 wl antenna. Whatever you do, don't slope the radials down on a 5/8 w antenna!!! The impedance will vary wildly with the l/d ratio and length of the antenna. It is reactive as well as resistive, and needs some form of matching at the base. 73 Tom From amsoft@epix.net Mon Jun 24 21:12:49 1996 From: Madjid SuperUser Newsgroups: rec.radio.amateur.antenna Subject: Re: HAARP info requested Date: Sun, 23 Jun 1996 17:23:14 -0700 Message-ID: <31CDDFF2.61E9@odyssee.net> References: <4q6th0$9rn@newsbf02.news.aol.com> <4qgrlv$ctt@newsbf02.news.aol.com> W8JI Tom wrote: > Someone is making a lot of money getting people all worked up over this. > It's because they are either ignorant or playing with numbers. In any > event, they are making things look much worse than they are (for a tidy > profit). > > The total power radiated is simply the transmitter power less any system > inefficiencies. Antenna gain doesn NOT increase the real power radiated, > so we are NOT bombing the ionosphere with the power that would run a small > city. > > The antenna is NOT focusing RF on one tiny point in the ionosphere, as > books by Dr. "Quack" suggest. Tom, You should go and read the USNavy HAARP info http://server5550.itd.nrl.navy.mil/projects/haarp/haarpIndex.html They themselves say that they will punch holes in the ionosphere and that the final power is in the GigaWatt range. If punching holes in the Ionosphere is not bombing, then what is? VE2GMI -- And God said, "Let there be light." And there was light, but Hydro Quebec said he would have to wait until Thursday to be connected. And God saw the light and it was good. Then he saw the quarterly bill and that was not good. From amsoft@epix.net Mon Jun 24 21:12:50 1996 From: mcduffie@hannibal.wncc.cc.ne.us (Gary McDuffie, Sr.) Newsgroups: rec.radio.amateur.antenna Subject: Re: black twin-lead phone line; How many Ohms? Date: Fri, 14 Jun 1996 22:22:03 GMT Message-ID: <31c1e5e8.31805474@164.119.101.2> References: <6c7cc$1622f.206@news.linknet.net> On Thu, 13 Jun 1996 11:20:58 -0400, Siegfried Rambaum wrote: > > Does anyone know anything about using the black 2-wire out-door > > telephone line as a feed line? Wonder what the feedline impedance on > > this stuff would be? At any rate, it looks like it would make good > > dipole and longwire stock. Anyone used this stuff before? > I would propose, that you read the ARRL Handbook. This stuff has an > impedance, if used for the intended use. But this impedance might be of > no concern to you, when you use it differently. If you cut that stuff > into dipole segments, and use all the wires inside the plastic jacket, > then the dipole resulting from it will have the impedance any other > dipole of the same geometrical arrangement will have too. However, I am > not sure, if you would have to adjust the dipole elements' lengths to > adjust for operating not with a single wire dipole but a multiwire dipole. > A good thing to have, when building antennas, is a noise bridge anyway. > So get yourself one, ghood used ones should be around for 40...50 bucks, > and less if they were homebrew... Reread the question... He is asking about the black drop line that is a two conductor cable, used for many years in the telephone industry. 30+ years ago, I was told this stuff was "close to" 75 ohms, and I used it for years to feed various antennas when I was a kid. Worked good. How it would compare to "real" feedline today, I don't know. We have much better equipment to measure such things today than we had then. Gary From amsoft@epix.net Mon Jun 24 21:12:52 1996 Newsgroups: rec.radio.amateur.antenna Subject: Re: Heavy Duty Install Message-ID: <1996Jun19.080852.81888@cc.usu.edu> From: tlzollinger@mae.usu.edu (Terry Zollinger) Date: Wed, 19 Jun 1996 14:11:23 GMT References: <31C79F8B.23C2@4dcomm.com> Alex Groza wrote: >I'm looking for some input in regards to installing antennas in areas >prone to ice, snow, wind, and all those fine things! >I'm planning on installing a VHF and UHF repeater system at approximately >9,000 ft. AMSL. The hilltop is in Southern California. During the >winter months it is unaccessable due to snow! Winds reach the 100 mph >mark. Ice forms on antennas as well as chunks of flying ice that hit >antennas. Last winter we lost a Stationmaster UHF antenna. >One antenna recommended by a ham in Colorado is the AEA IsoPole. He uses >a thick wall aluminum 1 1/4 inch mast. >Any other suggestions or hints? The antennas will be mounted on a >commercial tower. I definately don't want to use fiberglass. However, a >Comet 5 foot tri-band antenna that was mounted and center supported off >the side of a tower did last through the winter! We gave it a 25% chance >and the supported stationmaster a 50 / 50 chance! >Thanks.... >73's >Alex WB6DTR We have used super station masters in the past on our 10,000 ft. site they last thru maybe one or two winters then the insides break due to flexing from ice load. We are now useing a celwave exposed dipole and it seems to survive quite well. Terry N7PEG From amsoft@epix.net Mon Jun 24 21:12:54 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: HF multiband sloper Date: 24 Jun 1996 13:21:03 -0400 Message-ID: <4qmipv$f6j@newsbf02.news.aol.com> References: <4ql9pf$57c@nnrp1.news.primenet.com> In article , kingbp@ka1fqt.mv.com (Bryan King) writes: > >I've run out of ideas on how to get this antenna to perform properly. >Any ideas from the ham community would be greatly appreciated! > > >Thanks & 73, > > >Bryan 1/4 wl slopers are more appropriately called "sloppers". It's just blind sloppy luck that let's them work in most installations. Usually, the amateur has a large beam antenna above the slopper connection point, and that large electrical mass acts like a ground. In your case, you have a skinny little mast grounded (poorly) at the bottom. Even if it was perfectly grounded, the system would have almost no ground at all at the top on bands like 40 and 15 meters. That's because odd quarter waves invert impedance at each end. On 160, you have a 30 foot ground lead to a pathetic ground. On 80, the same. On 40, virtually no ground at all (it would work better with the base of the mast insulated). On 20, a half wave vertical mast radiator grounded at the bottom end, and so on.. Your best bet would be to install a second slopper and use it as the ground or counterpoise. This type of double slopper is sometimes called an inverted V...it works and looks like a dipole. 73 Tom From amsoft@epix.net Mon Jun 24 21:12:55 1996 From: n7ws@azstarnet.com (Wes Stewart) Newsgroups: rec.radio.amateur.antenna Subject: Re: Towers for beginner Date: Sat, 22 Jun 1996 15:51:28 LOCAL Message-ID: References: <31C643AF.39AD@redrose.net> In article <31C643AF.39AD@redrose.net> Mike Warner writes : >From: Mike Warner >Subject: Towers for beginner >Date: Mon, 17 Jun 1996 22:50:39 -0700 >Hello all, > Does anyone have a sugguestion concerning a good antenna tower for a new >ham on a 1/4 acre suburban lot. I am located in a valley and feel the >need to elevate my antennas, but don't really want to do alot of climbing >on my roof. I would like something that is safe, very easy to install and >operate. ie, crank down or tilt down? I think about the tallest tower I >can reasonably put on my lot would be about 40'. >Thanks, Mike N3XPD :) I love having that call sign after my name! Mike: First of all, congratulations on your new license. The US Tower MA-40 tubular crankup mast is probably the cleanest looking support you can find for a modest antenna. They are not inexpensive (IMHO). The going price seems to be $679. This will crank down to about 20' and up to 40'. They make a tiltover base, a rotating tiltover base and a raising fixture but these run into (many) more $$. Unfortunately, there is no good way to climb these, so your antenna is still 20' above ground without the tilt over options. If you located it near the house, you may be able to reach the top OK. Otherwise, 40' of Rohn 25 is probably your best bet. Properly installed and bracketed to your house, you wouldn't need guys for a modest antenna wind load. They aren't as pretty as the tubular thing, but it depends on your wallet. 73, Wes -- N7WS From amsoft@epix.net Mon Jun 24 21:12:57 1996 From: jgarver@ichips.intel.com (Jim Garver) Newsgroups: rec.radio.amateur.antenna Subject: Re: Help! 6 mtr antenna problem Date: 20 Jun 1996 17:38:41 GMT Message-ID: <4qc2b1$2vt@news.jf.intel.com> References: <4piadd$ccu@nnrp1.news.primenet.com> <4pr55u$2ab@infa.central.susx.ac.uk> In article , Marv Uphaus wrote: >>Matt Strandberg wrote: >>I recently tried to make a 6 mtr vertical antenna. I made a normal >>coaxial-fed dipole... >>The SWR is 4:1, and I am sure that the lengths are correct. >I recently tried the same thing for my IC-706 and got exactly the same >results... I had an old balun around and so I added that in the center and >voila, VSWR down to 1.5:1... Then I realized that the balun was a 4:1 >voltage balun... Never the less, it solved the problem... Ten turns on a >1.5" od toroid of some nebulous material... Tuning the rig across the band >and watching the SWR display shows a minimum at about 51 Mhz... The length >of the dipole is about 110"... The balun seems to have made the >difference... Alternatively, I would make a folded dipole out of the plastic 450 ohm ladder line and use a 1/2 wave coax balun to feed it. Broader bandwidth and a better match should result. Either way, I've found that the height of an end fed or center fed vertical dipole above the ground will significantly change the match. Best pattern is with the bottom end about one wavelength above the ground, or about 20 feet high for 51 Mhz. Move up or down to change pattern and, to some extend, impedance. Practically, I think a horizontal dipole works best in the lower part of the 6 meter band. Verticals for 52.525 Mhz FM maybe. 73, Jim WA7LDV -- jgarver@ichips.intel.com WA7LDV I don't speak for Intel From amsoft@epix.net Mon Jun 24 21:12:58 1996 From: rogerjb@earthlink.net (Roger J. Buffington; AB6WR) Newsgroups: rec.radio.amateur.antenna Subject: Antenna suggestions wanted Date: 21 Jun 1996 11:38:55 GMT Message-ID: <4qe1kf$p5t@paraguay.it.earthlink.net> Reply-To: rogerjb@earthlink.net (Roger J. Buffington) I am presently in the process of installing amateur radio on my 25 foot motorboat. I'd appreciate any suggestions re: the following. The radio I'm using is the Yaesu FT900AT. I am presently experimenting with the Spider antenna, and the Hustler mobile antenna. The boat has a metal railing (stainless steel) that goes halfway around the bo at. I have clamped (using a metal, stainless steel clamp) the antenna to this railing, using it as a ground (imperfect, but hopefully better than nothing). The SWR at its most resonant point, for both antennas, is about 2.5 to 1. The good news is that the Yaesu's antenna tuner is brawny enough to match this SWR, and therefore I can pump 100 watts into the antenna. I have made numerous contacts on both 40 and 20 using both the Spider and the Hustler. I would be interested in any suggestions regarding how I might be able to get the antennas resonant points to go below 2.5/1. Is this a reasonable objective? The losses at 2.5/1 are not that bad, especially since I'm only using 12 foot coax. Of course, with the poor ground I'm using, I realize that I'm probably only radiating a small percentage of the 100 watts (is this right ?) Incidentally, the above has occurred while the boat is still on dry land, bein g prepped by the boat dealer. Perhaps things will improve when it is actually in the water? All suggestions welcome. Roger J. Buffington AB6WR USC Law School Class of '97 rogerjb@earthlink.net "I want to die peacefully, in my sleep, like my grandfather. Not screaming, and in terror, like his passengers." From amsoft@epix.net Mon Jun 24 21:12:59 1996 From: Gene Marcus Newsgroups: rec.radio.amateur.antenna Subject: Re: ?Measuring Axial Ratio? Date: Mon, 17 Jun 1996 17:03:32 -0500 Message-ID: <31C5D633.749F@hiwaay.net> References: <4pui8u$rks@grandcanyon.binc.net> Reply-To: mmarcus@hiwaay.net To: Kevin Shea Kevin Shea wrote: > > In an attempt to build a circular polarized antenna (a > 1.7 GHz axial mode backfire helical antenna to feed a > parabolic reflector ( a 1 meter dish)) it would be great > if I could measure the cicularity i.e. the axial ratio of > the antenna. I haven't found any "how to" references. > I've heard that one can do it with a network analyser. I > don't have access to one. but I do have access to signal > generator, a sweeper and a spectrum analyser. > > Any ideas or pointers would be greatly appreciated. > > Hi Kevin, The axial ratio of your antenna may be measured by rotating a linearly polarized antenna excited with a signal generator or other low level source at the frequency of interest. The test must be performed in the far field with steps taken to minimize any reflection. Ideally, a step attenuator is connected in series with the antenna under test to a receiver with some means of indicating signal strength (s-meter). With the linearly polarized excitation antenna held stationary, a signal level reference point is recorded. As the excitation antenna is rotated around it's axis, the step attenuator is adjusted to set the signal strength indicator to the reference point. The difference in step attenuator reading is the axial ratio expressed in dB. Assuming your backfire helix is constructed properly, you should realize an axial ratio of less than 1 dB. The reciprocity theorem may be applied here by swapping the excitation antenna and the antenna under test. Hope this helps, Gene Marcus W3PM GM4YRE Huntsville, AL w3pm@amsat.org From amsoft@epix.net Mon Jun 24 21:13:01 1996 From: "Michael G. Katzmann" Newsgroups: rec.radio.amateur.antenna Subject: Re: Mosley PRO Date: Sat, 15 Jun 1996 20:53:11 -0400 Message-ID: <31C35AF7.9E910DA@access.digex.net> References: <4pnfjq$fb1@everest.vol.it> <31C2D522.3F96@freemark.com> Bruce Burke wrote: > > Marco Magnano wrote: > > > > Hallo to all the hams in this newsgroup. > > Is there anybody who owns a Mosley PRO-95 or PRO-96 ? > > I am looking for a multiband rugged and full performance > > yagi and I believe that these could be what I'm looking > > for. > > Infos and on air impressions are wanted > > 73, Marco > > IT9WPO > > Marco, > > Our radio club has a PRO-96. It performs very well > with one exception. Our minimum SWR occurs > below the band on 15 and 20 meters. All attempts to raise it > have not yet worked. Mosley insists it is the environment, > but I would tend to think we would see some variation in > SWR as the antenna was turned. It is on a 45 foot tower > atop a building with many, many other antennas! > (Total height is about 100 feet, or 30 meters) > I have exactly the same problem on my Mosely 57B. The people at Mosely are of f with the pixeys! First they gave me the stuff about other the environment, then they gave me a cock and bull story about my Heliax coax having too much capacitance (I don't know which physics b ook they are working from but 50 ohms through a 50 ohm coax cable gives 50 ohms at the other end in my book!). I have no confidence in that company what so ever and would not waste my time putting up one of their antennas, even if it came free!! BTW, the difference in minimum return loss (VSWR) would not be a problem by it self, but the Back to Front ratios are much poorer than advertised. -- |\ _,,,---,,_ Michael Katzmann ( NV3Z / VK2BEA / G4NYV ) /,`.-'`' -. ;-;;,_ - Broadcast Sports Technology Inc. |,4- ) )-,_. ,\ ( `'-' - Odenton, Maryland. U.S.A. '---''(_/--' `-'\_) michaelk@digex.NET (finger for PGP public key) From amsoft@epix.net Mon Jun 24 21:13:03 1996 From: D.N.Muir@massey.ac.NZ (Dexter N. Muir) Newsgroups: rec.radio.amateur.antenna Subject: Missing back-issues Date: 20 Jun 96 10:57:01 GMT Message-ID: <199606201057.DAA19439@UCSD.EDU> Greetings, again, from New Zealand! I sent this a few days ago, but have not had any replies: > I keep an archive of this Digest on my 24-hrs Packet station >for local Hams who have no Internet. Occasionally (though rarely), >either UCSD or my (Massey) mail server hiccups, and I lose one or >two issues. I would like to keep the archive complete, so am >seeking issue: > >V96 #300 (27 May) > > If any kind soul has kept this, I would appreciate a copy >(to email address below). > > Meanwhile, many thanks to Brian, and to all contributors. Since then, I have had another couple of hiccups, and am missing V96 #352 V96 #357 A further note: Yes, I have looked in the Archive, and occasionally manage to avoid posting like this by getting back-issues there. These ones, however, are not present: it seems the Digestifier only archives one Digest each day, though it can post more than one. Much valuable information is lost :-( Brian says there is a re-organisation in the wind, and hopefully this will improve the situation :-) I also archive Ham-Digital and TCP-Group from UCSD, and NOS-BBS from hydra.carleton.ca 's listproc (UCSD is a listserv), and similar problems occur there, too, though not so seriously as they usually only Digest once per day. Thanks in advance, and 73 de Dexter, ZL3LH -------------------------------------------------------------------------- | Dexter N. Muir Manufacturing Pilot Plant Technician | | D.N.Muir@massey.ac.nz Department of Production Technology | | Massey University, Palmerston North, New Zealand | | http://www.massey.ac.nz/~DNMuir/ | | "Honesty pays --- but not enough." "Modesty pays --- but even less!! " | -------------------------------------------------------------------------- From amsoft@epix.net Mon Jun 24 21:13:04 1996 From: Corporate1@notes.techni-source.com (Technisource) Newsgroups: rec.radio.amateur.antenna Subject: Antenna Engineer Date: 20 Jun 1996 22:51:03 GMT Message-ID: <4qckkn$5tf@comet2.magicnet.net> Reply-To: corporate1@notes.techni-source.com TECHNISOURCE JOB TITLE : Antenna Engineer JOB LOCATION: Melbourne For a continuously updated list of opportunities please visit our Web Page... http://www.techni-source.com ************************************************************************* TECHNISOURCE has the following opportunity out of its ORLANDO office. TECHNISOURCE REQUIREMENT NUMBER FOR REFERENCE: OR20017 JOB DESCRIPTION: Please reference requirement # with response. ------------------------------ Antenna Engineer REQUIRED SKILLS: ----------------------------- Antenna Engineer, RF, Design, test Feed's waveguide and forward reflector antenna. They must know how to setup and shoot antenna patterns.(This is key!!!) Technisource, one of the fastest growing and most respected suppliers of Technical expertise to the nation has opportunities both locally and nationwide. TechniSource has positions open for both consultants and members of our Technical Staff. Please Reply To: Vince or Kurt Technisource, Inc. Dept. - OR20017 3260 University Blvd Suite 185 Winter Park, FL 32792 Phone (800)940-9401 Fax (407)677-8525 EMAIL :orlando1@notes.techni-source.com WWW: http://www.techni-source.com * WHEN FAXING PLEASE USE THE HIGHEST RESOLUTION AVAILABLE (We Use OCR).* ************************************************************************* For a continuously updated list of opportunities please visit our Web Page... http://www.techni-source.com ************************************************************************* ____ From amsoft@epix.net Mon Jun 24 21:13:05 1996 From: Mike Valentine Newsgroups: rec.radio.amateur.misc,rec.radio.amateur.antenna Subject: Re: Belden 9913 Connector Source?? Date: Thu, 20 Jun 1996 11:47:54 -0400 Message-ID: <31C972AA.61C@ix.netcom.com> References: <4q12ko$jhc@news.icanect.net> <4q52gk$60j@dilbert.whoi.edu> Dean Heinen wrote: > > In article <4q52gk$60j@dilbert.whoi.edu> jvaldes@whoi.edu writes: > >From: jvaldes@whoi.edu > >Subject: Re: Belden 9913 Connector Source?? > >Date: 18 Jun 1996 01:58:44 GMT > > >Terry... take a look at 9914, I've not had good luck with 9913 here on > >the Cape. The spiral wound center conductor tends to "suck up" moisture > >then it gets cold and the water condenses in the cable. I've had water > >run out of the coax connectors. 9914 uses a foam core, it's a little more > >lossey than the 9913 but it stays dry!!! > >Jim > > Then you are most certainly installing it incorrectly. > > Dean > N7ZRS Hello, Dean. You'll need to go into a lot of detail to explain how to install connectors on 9913 "correctly". Jim is only one among a large number of hams that have seen problems weather-proofing 9913. In long runs, it may well be impossible. It seems that the connector has to have nearly hermetic qualities to prevent water ingestion due to osmotic pumping of humidity into the central air-cavity of the cable. The major problem seems to be around the jacket-to-shell mating surfaces. I have had some success using flooded-joint heat-shrink (underground cable TV style) around the entire connector, cable shank, and whatever it connects to (other cable, antenna connection, etc). My opinion (and I can put on K-connectors @ 40 GHz that sweep well), is that only foam-core low-loss coax should be used out-of-doors. Belden 9914 is a good idea as well as Times LMR-400, LMR-600, etc.. I use Andrews 1/2" Superflex for jumpers on my VHF/UHF SSB/CW system. Belden 9913 is really an RG-8 sized version of air dielectric Heliax. Air (with spiral centering insulator)dielectric Heliax is ALWAYS used with a refrigerating dryer or low-pressure dry-gas purging on any out-of-doors run, otherwise it fills up with condesation. I have not seen refrigerated dryers for 9913 on the market. There are many, many stories about how somebody's 9913 run had all of a sudden developed a high SWR. One such person took the cable into work and put it on a time-domain reflectometer to look for a fault. When he located the point a the bottom of a loop, he drilled a small hole into the cable to see what it was. The high-SWR then "ran out onto the floor". The cable then tested OK. It happens all the time. Cordially, Mike Valentine - WA8MSF From amsoft@epix.net Mon Jun 24 21:13:08 1996 From: mdenis Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Hopeless to run HF voice at 100 watts? Date: Wed, 19 Jun 1996 09:34:35 -0500 Message-ID: <31C80FFB.314C@netnet.net> References: charles copeland wrote: > > I recently got my general, and have trying my luck on HF voice > using a TS820 running 100 watts, antenna tuner, and a 64 foot folded > dipole at 7' in my first floor apartment (also a Carolina Bug Catcher > sitting on mag mount on floor with two 30' folded counter poise wires). > > My luck has been rotten, (with exception of 10 meters). I've talked > to three HAMS on 20 meters only to have to struggle just to get > them to recognize my callsign. > > This brings up my question: Is it hopeless to run HF voice at 100 watts? > > If I were to get a inverted V dipole up at 40' would I have the same > lousy luck? What cheap portable antenna would be most efficient? > > I know two other HAMS who have recently gotten their general, > and both report lousy results on 20m-160m running 100watts. > Both live on third floor apartments using folded dipoles. Both rarely > are able to snag a QSO. > > What about running mobile? A 6' whip should pale to a 60' dipole on 3d floor ? > Seems 100 watts and a whip would be worse than hopeless. > > Is 100 watts sufficient when the sunspot cycle picks up? > > Are 20m-160m bands strictly the domain of the "big guns" > running 1500 watts, 100 foot towers, and monster beams? > > If this is so, what is the minimum setup to operate effectively? > > 400 watts, 600 watts, 1000 watts? > > 30', 40', 60', 100', tower? > > antennas? Hi Charles, I empathize with trying to operate HF from an apartment location. I would try all means to get an antenna outside, if at all possible. There are several interesting articles posted on the web that speak to 'clandestine' wire antennas. If that is not an option, I would suggest something like the AEA Isoloop. While it is a compromise, it will allow you to make contacts on HF at the 100 watt level. If you disguise it right, it will look like a bird feeder and you can hang it outside a patio door. Of course, as in most antennas, higher is better. I'd stay off 20 meter ssb while in the apartment. Usually you will generate tons of RFI that your neighbors will just not appreciate. Also, you'll need to monitor your VCR when your on 80 meters. Try 20 meter CW running QRP at night and you'll do well and you won't bug your neighbors (and your apt. manager won't bug you ;) ) Good Luck es 73 Marc KD0QO From amsoft@epix.net Mon Jun 24 21:13:10 1996 From: fbsfam@actrix.gen.nz (Forbes Family) Newsgroups: rec.radio.amateur.antenna Subject: Re: Building a QUAD for 11 meter (CB band) Date: Sun, 23 Jun 1996 04:20:45 GMT Message-ID: <4qikdl$rph@asgard.actrix.gen.nz> References: <31c6e422.3761428@news> dr-guru@cuci.nl (Ton Muller) wrote: >I want to build a 2 elemts quad for the CB band (27.500 mhz) ,but do not know >how to calculate the driven and the reflector. The elements of a Quad are actually just simple 1.0 wavelength circular loops which have been formed into a square shape to make them easier to construct and support on a boom. Although such a loop is a resonant structure, it has a very low Q and provides very good broadband performance. This is great from a home construction point of view as it makes the dimensions non critical. An everyday example of this is the popular single turn circular loop antenna used with many portable TVs for indoor reception of *all* UHF channels. The directivity achieved is generally better than 3.5dBi across the entire band if designed so that loop circumference is 1.0 wavelengths at 470 MHz and 1.7 wavelengths at 806 MHz. Input resistance over this range varies from about 100 Ohms at the bottom end of the band to several hundred Ohms at the top. VSWR into a 300 Ohm feeder is typically closest to 1 when the loop circumference is about 1.3 wavelengths. Applying the above to your proposed 11 meter Quad antenna, it would seem you cannot go far wrong so long as you design for an element circumference somewhere in the vicinity of 1.0 to 1.3 wavelengths. To achieve maximum directivity (and hence gain), I'd recommend basing your design on the once popular *ZL Special*. This is a simple two element antenna which operates in the *end fire with increased directivity mode* where both elements are actively driven and interconnected using a criss-crossed two wire transmission line to achieve a 135 degrees phase lag at the rear element. The finished antenna is fed from the front element (visually just like a log-periodic, although the theory of operation is actually quite different). The two elements are spaced 1/8th wavelength apart along the boom. When using dipoles in this configuration, the rear element is generally made a *resonant* half wavelength long and the front element is cut approximately 5% shorter. Hence, for your Qaud, I'd suggest the following dimensions (in free space wavelengths): Rear element circumference: 1.2 Wavelengths Front element circumference: 1.14 Wavelengths Element Spacing: 0.125 Wavelength Expected directivity should be in the vicinity of 9dBi ( 7dB gain over a dipole), assuming an E-Plane beamwidth of 90 degrees and an H-Plane beamwidth of 140 degrees. Bandwidth and front to back ratio should be exceptional and I'd guess feed point impedance will be something like 40-50 Ohms (balanced). Cheers, and good luck with the project. Ged Forbes From amsoft@epix.net Mon Jun 24 21:13:12 1996 From: kferguson@aquilagroup.com (Kevin AstirCS "1U" KO0B) Newsgroups: rec.radio.amateur.antenna Subject: Re: Hopeless to run HF voice at 100 watts? Date: Wed, 19 Jun 1996 08:41:17 -0700 (PDT) Message-ID: <4q93d5$fg7@blixen.aquilagroup.com> References: charles1@netcom.com (charles copeland) wrote: >antennas? You have questioned your own answer! Many apartment buildings are made of reinforced concrete...The re-bar makes a pretty effective Faraday cage, and there is lots of really lossy "stuff" right next to the antenna. By "folded dipole" I assume you mean you took a plain old 1/2 wave dipole , and bent the legs up to fit into your apartment. This results in lots of the signal canceling out. If you must use this antenna, at least get as much of the middle (high current part) , bothe sides, as straight as you can....then fold the ends. You really need to get something, _anything_ at_all_ , outside. Plenty of folks run only 100W on 80M mobile with good results. 80 is a noisy band, and typically has the most "need" for high power. Look into the many articles on "stealth" antennas. bare (or varnished) AWG 24 wire is really hard to see..just keep it high enough not to trip or closeline sombody...and of course stay clear of power lines. Random wires will be your cheapest/easiest option for a steallth antenna. For these you need either a tuner (simple L-network is fine) or an unatural amount of luck. (only got good match on random hunk of wire once in my life) I had really good luck with a MFJ econo-tuner when I lived in apartment. I read all kinds of bad things about MFJ tuners, but this thing has worked great for me. Also, if running random wire, try to arrainge a rellay solid ground connection. Make sure you have a clean signal...resist the urge to crank up the drive to get more uumph. A splattering, overmodulated signal is really hard to copy. Some will even avoid you on general principle. Ask a local ham to monitor you, and write down the settings for best signal. Set yourself apart from the crowd. Unless you are a masochist, don't bother jumping into a pileup. You will soon get a feel for how weak a signal you can expect to hear you. Look for that forlorn, lonely guy been calling CQ for 5 minutes with no answer. That guy will MAKE a way to copy your signal! And, as others have already told you, CW will make all the difference. Conseder a field trip to a nearby park (with BIG trees) for some+ If you are still seriously considering an amplifier, here are some issues you need to consider. 1) The safety of running high power to an indoor antenna has been questioned by many. 2) In an apartment, running a linear is just begging for TVI problems. Your neighbors will almost certainly involve the apartment management in this..... 3) A better antenna will be cheaper than a linear, and less of a TVI problem. You will also hear better with it..win, win, win. 4) I don't suppose your apartment is wired for 230VAC...no, I didn't think so. So you are limited to about 1S unit of improvement. (~500W is max you can run off 110V) Take heart. This is only a crude guess, but HF ops I know , only maybe 20% even own an amplifier. From amsoft@epix.net Mon Jun 24 21:13:14 1996 From: "Thomas W. Castle" Newsgroups: rec.radio.amateur.antenna Subject: Re: Help! 6 mtr antenna problem Date: Thu, 20 Jun 1996 04:02:09 -0400 Message-ID: References: <4piadd$ccu@nnrp1.news.primenet.com> <4pr55u$2ab@infa.central.susx.ac.uk> Reply-To: "Thomas W. Castle" To: Marv Uphaus On 18 Jun 1996, Marv Uphaus wrote: > >Matt Strandberg wrote: > >I recently tried to make a 6 mtr vertical antenna. I made a normal > >coaxial-fed dipole... > >The SWR is 4:1, and I am sure that the lengths are correct. > > I recently tried the same thing for my IC-706 and got exactly the same > results... I had an old balun around and so I added that in the center and > voila, VSWR down to 1.5:1... Then I realized that the balun was a 4:1 > voltage balun... Never the less, it solved the problem... Ten turns on a > 1.5" od toroid of some nebulous material... Tuning the rig across the band > and watching the SWR display shows a minimum at about 51 Mhz... The length > of the dipole is about 110"... The balun seems to have made the > difference... > Marv, K4BVG... Having made "lots" of dipoles for 10, 6, 2, 220, 440 & ATV freqs, I'm just wondering about your installations, not so much your dimensions. When one hangs a dipole horizontaly, they usually do so in the clear. They use nylon or dacron to pull up the antenna an if nothing else, let the feedline hang from it; if hung from the ends only... So the end result usually works out ok..? When one hangs one dipole vertically, the method used often dictates its worthyness... It needs to be in the clear from metal It works for me: to hang them about 2' to 3' off the side of my tower. I use a piece of PVC pipe 1" with a 1" dowel rod in it, this stiffens up the top mounting point. With a eye bolt near the end to run my pull cord thru to raise an lower the antenna. Why climb up an down more than you need to...? Also I use 2 PVC caps on the ends of the mounting "bar" an a U bolt or 2 to mount it to my tower or push up pole. At the feed point I will usually put a current balun <6-8 turns >> 8 to 9 inches in dia> That is fed in at a 90 degree angle to the antenna an ties off to the support structure, so the feed line is seperated from the antenna... The bottom end of the antenna has a stand-off or support bar just like the top, but near ground level. This allows me to: tie the lower part of the dipole off straight an snug... I have 3 dipoles on each of my towers at present, mounted in this manner. My favorite dipole for quick down an dirty use is: the coaxial dipole... The dipole an feed line are one in the same... They are quick, easy an work great vertically.... Take a piece of coax more than long enough to go from your hanging point to your place of connection to rig. Skin the outter plastic off the coax about 1-2" longer than 468/freq in Mhz/2 dimension. Then with a pencil or other device open a slot in the shield without destroying it. Force the center insultation an center conductor backwards thru this slot or hole per say. With a little patients, you'll end up with the empty sheild still attached an the center conductor with insulation. Now you can strip off the insulation from the center conductor or leave it on if you figure the antenna abt 3% longer to compensate for the insulation... Anyhow measure out from the point where the 2
seperate the appropriate distance while pulling the antenna out straight an trim... Leave enough to mount your pull cord or insulator, before setting the final cut. I have made up hundreds of these for field day, newbies or for trying out a rig I didn't have a ready made antenna for... I tape or silicone the coax jacket & center conductor to keep water out for as long as possible..? BTW> be sure to tape the sheid back to the feed line at multiple points in a straight manner. With this antenna, you want the lower part to parallel the feed line back down to the ground. This idea works for horizontal dipoles as well, just make it like a "T" with the feed line dropping away from the elements... Heres a little antenna that can cover from 11, 10, 6, 2, 220 & 440... For those who would rather assemble one than build one... Its the AV-160 by Avanti.... It is a Alum. ant with stand off multiple piece elements that telescope together overall lenght 18' 6" so you can trim it or assemble it to any length within its range. An its cost is less than $20.00. It is available at a lot of suppliers whether "CB" or Ham... It comes with a really nice center assembly that mounts the antenna to the "standoff off assembly" an gives you easy coax termination that can be sealed for really long time usage without hassels... The company that originally made them was bought out by Antenna Specialists an to my knowledge are available to most areas. I've got 6 still left in the box for future projects, that justify their use... Good Luck - Hope this helps or at least gives you an idea or 2. To "ME" nothing seems to beat a resonant antenna... I'm no expert, but do enjoy building them an getting them to really work as good as they can... 73 De Tom KD4QHH From amsoft@epix.net Mon Jul 01 12:22:01 1996 From: mjappine@news.hit.fi (Mika Antero Jäppinen) Newsgroups: rec.radio.amateur.antenna Subject: Multiband-dipole HELP needed! Date: 23 Jun 1996 12:23:23 GMT Message-ID: <4qjcvr$6f9@perjantai.hit.fi> Hi, I am looking for multiband dipole antenna for HF which would cover 80-40-20-15-10 meter bands. Biggest promblem is that I had to hang it over metal-roof approx 6-7 feet high from it and this is same as put it inna ground level.. So is there any antennas (dipole-horixzontal no yagis) which might perform atleast well on these kind of circumtanses? I guess I had to go and buy vertical 8( Antero Jappinen Email mjappine@maanantai.hit.fi Packet OH2LJH@OH2BAR.FIN.EU From amsoft@epix.net Mon Jul 01 12:22:02 1996 From: kenmccoy@aol.com (Ken McCoy) Newsgroups: rec.radio.amateur.antenna Subject: NEWBIE: impedance of 2m 5/8 wave ground plane Date: 24 Jun 1996 09:31:33 -0400 Message-ID: <4qm5bl$an0@newsbf02.news.aol.com> Reply-To: kenmccoy@aol.com (Ken McCoy) Forgive me if this question has an obvious answer; I haven't been able to find it anywhere. Is the angle of the ground plane segments for a 5/8 wave vertical the same as that for a 1/4 wave for 50 ohms (i.e., 45 degrees). Or, what is the impedance for a 90 degree angle? Thanks and 73, Ken KF4BQF kmccoy@tophat.stetson.edu From amsoft@epix.net Mon Jul 01 12:22:03 1996 From: jafl@msg.ti.com (Jim Flanders) Newsgroups: rec.radio.amateur.antenna Subject: Re: DDRR antenna -reply to comments Date: 24 Jun 1996 13:34:47 GMT Message-ID: <4qm5hn$jij@ganesh.mc.ti.com> References: <4qbio5$vkp@ganesh.mc.ti.com> <4qh2a6$fic@newsbf02.news.aol.com> The neon baulb peaks brightness at the capacitor end. Jim In article <4qh2a6$fic@newsbf02.news.aol.com>, w8jitom@aol.com says... > >Hi Jim, > >In article <4qbio5$vkp@ganesh.mc.ti.com>, jafl@msg.ti.com (Jim Flanders) >writes: > >>Yes - The baulb lit on only the horizontal sections - The vertical >>section is like this: >> >> /----- >> | ^ >> | feed (5.5" from vert. section) >> ground > >So are you saying the bulb lights anywhere along the top ring, but no >where on the vertical section? > >Does it light evenly along the whole ring? > >73 Tom From amsoft@epix.net Mon Jul 01 12:22:04 1996 From: bigkid@interaccess.com (Big Kid) Newsgroups: rec.radio.amateur.antenna Subject: Need help with portalbe antenna Date: Mon, 24 Jun 1996 17:52:52 -0600 Message-ID: I would like to operate portable hf from hotel rooms as I travel. I was thinking of the MFJ wire/counterpoise tuner with a random length wire thrown into a tree. I was also thinking about a helically wound mobile antenna mounted at ground level with a few quarter wave radials attached to the base and fed with coax and tuner. Does anyone have an opinion on how well either of these configurations would work? From amsoft@epix.net Mon Jul 01 12:22:05 1996 From: Bruce Williams Newsgroups: rec.radio.amateur.antenna Subject: Dual Band vhf/uhf Mobile Antenna Date: Mon, 24 Jun 1996 21:56:55 -0700 Message-ID: <31CF7197.672F@net1.nw.com.au> Does any one know if it is possible to purchase an on-glass dual band vhf/uhf mobile antenna? 73's Bruce VK6CX From amsoft@epix.net Mon Jul 01 12:22:06 1996 From: tegennett@hfs.purdue.edu Newsgroups: rec.radio.amateur.antenna Subject: Field Day Antenna Date: Tue, 25 Jun 96 09:30:48 PDT Message-ID: While the subject is fresh in everyone's mind.... Can you recommend an "ideal" Field Day antenna? Here's my definition of ideal : -Easy to put up and take down -Omnidirectional We used two different antennae this past weekend. A horizontal loop/longwire for CW. Four lines up in the trees, unroll the wire from the spool, and we could work everything we could hear, usually on the first or second call. For SSB we used two lazy H's erected at right angles to each other, one oriented east-west and one north-south. Each required four lines into the trees (a total of 8). Very labor consuming to put up and take down, to keep everything from getting tangled. There were often lots of stations we could hear that could not hear us. The first antenna was ideal, the second was not. Anybody use a commercial vertical with success? Tim KF9WX From amsoft@epix.net Mon Jul 01 12:22:07 1996 From: Chris Boone Newsgroups: rec.radio.amateur.antenna Subject: Re: Dual Band vhf/uhf Mobile Antenna Date: Tue, 25 Jun 1996 10:28:01 -0700 Message-ID: <31D021A1.6A3B@earthlink.net> References: <31CF7197.672F@net1.nw.com.au> Bruce Williams wrote: > > Does any one know if it is possible to purchase an on-glass dual band > vhf/uhf mobile antenna? > > 73's Bruce VK6CX Larsen KG-2/70 is the best you can get....... 73 Chris WB5ITT From amsoft@epix.net Mon Jul 01 12:22:07 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Buried radials: Insulated or bare? Date: 25 Jun 1996 12:52:22 -0400 Message-ID: <4qp5g6$f4u@newsbf02.news.aol.com> References: <4qlqep$5j6@doc.zippo.com> In article <4qlqep$5j6@doc.zippo.com>, S.Y.Stroobandt@e-eng.hull.ac.uk writes: >My guess is that the performance level of both should be about the same, >except that insulated radials will last longer. > >73 de Serge Hi Serge, The performance will be exactly the same. The only diffference will be in the life of the radial. 73 Tom From amsoft@epix.net Mon Jul 01 12:22:09 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: V/UHF connector losses? Date: 25 Jun 1996 12:59:02 -0400 Message-ID: <4qp5sm$fai@newsbf02.news.aol.com> References: <4qmo0a$87s@uwm.edu> In article <4qmo0a$87s@uwm.edu>, jw@alpha1.csd.uwm.edu (John Clifford Wilke) writes: > >Question: Will upgrading to N connectors help raise those elusive grid >squares out of the mud? (and bring MY signal out of the mud?) > > Not unless you have a whole bunch of connectors in series... The loss in the UHF type connector is very low, the only real problem is it adds a slight bump in the line. Fortunately the bump is so short it won't have much effect. 73 Tom From amsoft@epix.net Mon Jul 01 12:22:12 1996 From: jafl@msg.ti.com (Jim Flanders) Newsgroups: rec.radio.amateur.antenna Subject: Re: HF multiband sloper Date: 25 Jun 1996 13:09:42 GMT Message-ID: <4qooem$nij@ganesh.mc.ti.com> References: Doug Demaw did a lot of research on the sloper. If I remember right, he found that the half-sloper (1/4 wave antenna) requires much tinkering to get the swr down. Also - the angle of the antenna should be 50 degrees, and the bottom should be about ten feet above the ground. I suspect that with using only a 30 ft mast, your not able to meet these criteria. Let us know some more about the installation. Jim W0oog/5 In article , kingbp@ka1fqt.mv.com says... > >I recently bought an Alpha-Delta DX-B 1/4 wave sloper that covers 160 - >30 meters. I've been having alot of trouble getting it to perform >satisfactorily on all of the bands, except for 30 meters. I currently >have this antenna fed by a 120' run of RG8-X. The feedpoint is at the top >of a 30' aluminum mast and I've attached an aluminum ground wire to it >that acts as counterpoise. This is grounded from the feedpoint to a 4' >ground rod at the base of the mast. I have very high swr with this >particular antenna and thus use an antenna tuner to match the xcvr to the >antenna system. On 160, I cannot tune up properly, unless I attach a >capcitance hat at the end of the antenna closest to the ground. That is >approximately 10' off the ground. The guy wires for the mast are dacron >rope. There is a 6 meter vertical on top of the mast. To date this is >perhaps the best configuration of the antenna. > >I've run out of ideas on how to get this antenna to perform properly. >Any ideas from the ham community would be greatly appreciated! > > >Thanks & 73, > > >Bryan From amsoft@epix.net Mon Jul 01 12:22:13 1996 Newsgroups: rec.radio.amateur.antenna From: jdc@cci.com (James D. Cronin) Subject: Re: Dual Band Base Antenna...? Message-ID: References: <31C71F98.234B@polar.polarcomm.com> Date: Tue, 25 Jun 1996 16:48:38 GMT In article <31C71F98.234B@polar.polarcomm.com>, Connie Hulst wrote: >I am going to be putting up a dual-band antenna at my home. I have >narrowed the field down to a Comet GP-3 or a Diamond X-50A. In the >AES catalog, the Diamond is $15 more, although the specs seem to be the >same. Is the Diamond really that much better quality? > >If anyone has any remarkably wise advice, please E-Mail me as well as >posting the reply--my news server is VERY unreliable. > >73 de Nick Hulst, AA0VY I picked up a Taiwanese knock-off at the Rochester, NY hamfest for under $50. It's construction is close to the original; a 5/8 wave over 5/8 wave inside a 2-piece fiberglass tube. The price was right and it works OK, too. 73..Jim N2VNO From amsoft@epix.net Mon Jul 01 12:22:14 1996 From: Mark Schoonover - KA6WKE Newsgroups: rec.radio.amateur.antenna Subject: Re: Full Wave Loops Date: 25 Jun 1996 16:53:00 GMT Message-ID: <4qp5hc$791@usenet1.sjc.in.sel.sony.com> References: <31C439AC.2E8D@light-house.net> <4qb0pj$87s@newsbf02.news.aol.com> <31CAFAFD.7F9D@border.com> Rod Adkins wrote: >Pricemw wrote: >> <<<< MUCH SNIPPED>>> >quarter-wave 75-ohm matching section at the antenna to match the >approx 100 ohm of the loop to 50 ohm coax. I haven't used a balun. > >I have found that it is *MUCH* easier to tune loops if the geometry is >as near a square as possible. > >Rod, VE3INE Rod: When you calculated for the quarter wave 75 ohm matching section, does one have to take into account velocity factor?? I'm planning on a 2m loop -- which puts the matching section at around a foot using velocity factor. Is my thinking correct??? 73's Mark -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Mark Schoonover -- KA6WKE E-Mail: schoon@cts.com San Diego, CA Kenwood R-1000, BC2500XLT, PK232MBX/JVFAX, 66' Indoor Dipole ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ From amsoft@epix.net Mon Jul 01 12:22:15 1996 From: kenj@fesi.com Newsgroups: rec.radio.amateur.antenna Subject: BALUN needed on Stacked J-pole Date: 25 Jun 1996 16:55:31 GMT Message-ID: <4qp5m3$bj@purple.marble.net> I am planning to build a 2 meter, stacked J-pole for a base station antenna. I will use 1/2 or 3/4 inch copper pipe for construction. What is the feedpoint impedance of a J-pole? Do I need to use a 4:1 balun to feed the antenna or is direct coax OK? Coax will be RG-8. The maximum forseeable power is 60-100 Watts. Ken KC5UNN From amsoft@epix.net Mon Jul 01 12:22:16 1996 From: kenj@fesi.com Newsgroups: rec.radio.amateur.antenna Subject: Windload, how to calculate? Date: 25 Jun 1996 17:00:10 GMT Message-ID: <4qp5uq$bj@purple.marble.net> I would like to learn how to calculate the windload (effective square feet?) for an antenna. I could use commercial antenna specs to estimate windload but would like to learn the theory. Does the windload estimate take into account the tourqe induced by short vs. long booms? Ken KC5UNN From amsoft@epix.net Mon Jul 01 12:22:19 1996 From: grhosler@mmm.com (Gary Hosler - KN0Z) Newsgroups: rec.radio.amateur.antenna Subject: Re: Stacking Yagis Date: Tue, 25 Jun 1996 18:42:13 GMT Message-ID: <4qpc5l$db0@dawn.mmm.com> References: <4qng6d$ndk@newsbf02.news.aol.com> kk5ep@aol.com (KK5EP) wrote: >I am looking for a good resource concerning stacking yagis. I have a >Force 12 C3 and I would like to add a C4XL or an "Elite force" 20/40 yagi >. Can these two antennas be stacked in order to take advantage of more >elements on 20 mtrs? If so, how many feet of separation is optimal? I am >primarily a dx-er who also contests. Total weight of these antennas is >approx 100 lbs. Tnx, pse e-mail direct. 73, Mike. KK5EP. I wouod suggest you get a hold of Lawson's book on Yagi Design. It has quite a bit of detail on stacking distances, pattern effect, impact on F/B & gain, impedance matching, switching networks, etc.. I would think that you C3/C4XL could be stacked very nicely as they are basically the same antenna except for the 40M capability on the C4XL. As for spacing, it will be a compromise. Depends on which band you want to favor. If it were mine, I would opt for the lower antenna (C3) at a height of about 50-60 ft with the upper antenna (C4XL) at 100-120 ft. In any event you would want to shoot for about 1 wavelength spacing (or a bit more). Spacing greater than 1.2-1.3 wavelengths will result in gradual decrease in gain. Less spacing that about .9 wavelengths will result in a degraded pattern and reduced F/B. Of course the ususal cavet applies in that yagis of the long boom variety and additional elements will be affected in a slightly different manner. You may also want to talk with Tom Schiller at Force 12 as I'm sure he has played with this combination. Remember,...your DX mileage may vary.... Opinions expressed herein are my own and may not represent those of my employe r. From amsoft@epix.net Mon Jul 01 12:22:20 1996 Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc From: tomz@premier1.net (Tom Zoch) Subject: Re: Kenwood and Microsoft say ham radio dead Message-ID: Reply-To: zoch@data-io.com References: <31C618E5.3567@ix.netcom.com> <1996Jun20.133842.10513@ke4zv.atl.ga.us> <31CBCD4B.751C@ccsnet.com> <4qoq6n$nij@ganesh.mc.ti.com> Date: Tue, 25 Jun 1996 20:28:29 GMT Don't forget Bill Gates (Microsoft) is one of the Major players behind the Leo Satellite people who want to take over our Ham bands. It is no surprise that they want to call it dead! Apparently Kenwood will be making the electronics for them and are also willing to turn there backs on us. I will never consider buying a Kenwood product. Tom KC7PMQ From amsoft@epix.net Mon Jul 01 12:22:21 1996 Newsgroups: rec.radio.amateur.antenna From: wa2ise@netcom.com (Robert Casey) Subject: Re: "Infinite Baluns" question Message-ID: References: <19960622.094726.87@southlin.demon.co.uk> Date: Wed, 26 Jun 1996 01:22:30 GMT In article <19960622.094726.87@southlin.demon.co.uk> graham@southlin.demon.co. uk writes: >Hello Folks > >I have trawling my books to find anything on "infinite baluns", or >perhaps something called an "infinite balun technique". Sadly, we >find nothing. The only use of the word "infinite" refers to the >stub sleeve on a [coaxial balun] that tries to be an infinite >impedance to current that might otherwise flow on the outer >conductor of the coax. > Some baluns are built using lengths of transmission lines, wound thru a toridal core to create an inductance as seen from the outside of the outer shield of the coax (assume you used coax as your transmission line). The signal on the inner conductor and the inside of the outer shield doesn't "see" the inductance. Use enough turns on the torid, and the impedence of the outside would be a few thousand ohms, neglidgable compared to 75 ohms. If you had some 150 ohm coax (I never seen 150 ohm coax myself), you could put 150 ohm dummy loads (seperately) at the far end of these coaxes, and wire them parallel to the 75 ohm source coax, and things would match. and at the far end you could remove the resistors, wire the coaxex in series (shield of 2nd coax to inner conductor of 1st coax, and load with 300 ohms dummy load across the shield of the first coax to the inner conductor of the 2nd) and you're almost have a balum. OK, but I shorted the center conductor of the 1st coax to the grounded shield of the 2nd coax. Now, if I coiled the coaxes before wiring them up, the old short path now looks like an inductance of several thousand ohms (useing enough turns). Above some frequency band, and up to microvave freqs (when coax attenuation kills it), you have a 1:4 balun. That's what's inside those TV baluns from the cable company and radio shark. From amsoft@epix.net Mon Jul 01 12:22:22 1996 From: jackl@pinetree.microserve.com (WB3U) Newsgroups: rec.radio.amateur.antenna Subject: Re: Feeding Vertical with Balanced Line Date: Wed, 26 Jun 96 05:47:45 GMT Message-ID: <4qqj2m$qbt@crash.microserve.net> References: <122456@gate.kc5aug.ampr.org> <4qmicv$f0j@newsbf02.news.aol.com> w8jitom@aol.com (W8JI Tom) wrote: >If the line is less than perfectly balanced, this type of balun >(or even a link coupled tuner with an output section employing >grounded components) will usually aggravate the problem. Tom, What's your best guess as to why Johnson chose to ground the "center" of the output caps in the Matchbox? Do you think they just happened to design it like that and it worked, so they left it as-is? The more I read on this topic, the more convinced I am there's no real rhyme or reason for the ground. 73, Jack WB3U From amsoft@epix.net Mon Jul 01 12:22:23 1996 From: andy@pythagoras.org (Andy Nourse) Newsgroups: rec.radio.amateur.antenna Subject: How do I attach an HF antenna to a Honda? Date: 26 Jun 1996 08:50:49 GMT Message-ID: <4qqtl9$gja@masters0.Internex.NET> I have a Honda Civic hatchback and have found a notable lack of places to attach antennas. Most other relatively new cars seem to be this way too. A bumper mount won't work, there is no way (that I've found) to attach it to the plastic-over-foam-over-metal bumper. A trunk mount won't attach to the hatch, there's glass there. I'm using mag-mounts for 10, 6, and 2, but those won't be adequate for the lower bands (I have actually seen a really short 20m antenna that could be held by a really sturdy magmount, but it seems to short to be any good). I don't want to drill holes in the roof. From amsoft@epix.net Mon Jul 01 12:22:26 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Ladder line variability questions Date: 26 Jun 1996 09:12:02 -0400 Message-ID: <4qrcv2$kvh@newsbf02.news.aol.com> References: <4qqiq5$8dq@newsbf02.news.aol.com> Hi Pete, In article , psoper@encore.com (Pete Soper) writes: > >My conclusion then is that there is likely to be a lot of variability >among same-sized ladder lines based on their conductors going from >18 to 14 gauge and a smaller variability with differences in >insulation thickness and proportion of the line open via its windows. >I should go for both the smallest conductor and thinest insulation and/or >largest amount of window cutouts to get the highest possible Zo and >lowest weight (my original goals). Making my own open wire line is of >course the guaranteed way to get what I want but I'm not convinced >I can make something that will last well with the periodic hula dancing >my trees do. I am "tickled pink" to get lower than 450 ohm line. A lower impedance is better in my applications. The low Z line will have lower losse, be less susceptable to weather effects, last longer, and handle more power. With the antennas I usually use, it gives me less impedance excursions with frequency...and keeps the feedpoint impedance more constant. I'm glad the manufacturer had no idea what he was doing. I just hope he makes "300 ohm" line soon, it'll make a good 75 ohm feedline, hi.. 73 Tom From amsoft@epix.net Mon Jul 01 12:22:26 1996 From: Madjid Newsgroups: rec.radio.amateur.antenna Subject: Re: HAARP info requested Date: Wed, 26 Jun 1996 11:14:04 -0700 Message-ID: <31D17DEC.54C@odyssee.net> References: <4qojpd$dgt@ra.nrl.navy.mil> Edward J. Kennedy wrote: > Nowhere in our server does it say that HAARP can "punch holes" in the > ionosphere. HAARP has no such capability.snip > Ed K3NS Thanks Ed, I just wanted to know if HAARP people monitored this newsgroup. ---- Madjid, VE2GMI Internet: orion@odyssee.net Antenna simulation program NEC4WIN found at: http://www.coast.net/SimTel/SimTel/win3/hamradio/nec4w15.zip From amsoft@epix.net Mon Jul 01 12:22:28 1996 From: Madjid Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Growth Rate is UP not down! Date: Wed, 26 Jun 1996 11:37:26 -0700 Message-ID: <31D18366.4776@odyssee.net> References: <31C618E5.3567@ix.netcom.com> <1996Jun20.133842.10513@ke4zv.atl.ga.us> <31CBCD4B.751C@ccsnet.com> Patrick Tatro wrote: > Correct me if I am wrong BUT ..... > > Who said continued growth is a good thing? > Sixty years ago the joy of the hobby was for two > operators to make contact with rigs they built and > antenna's they designed. > > These days the bands are crowded with Ham > want-to-be's, DJ want-to-be's and people who > wouldn't know good manners if they jumped up > and bit them. > > I for one say its time for this hobby to > down-size. Maybe those people who get their > license and then spend all their time bad > mouthing the hobby will find new things to bad > mouth (like net surfing). The true joy of amateur > radio will always be there no matter how much it's > bad mouthed. > > Nuf Said > Pat N0WCG This whole growth think is plain BALOONEY. As an example in the Canadian RAC magazine, the editors continuously complain about the hobby going to die because no new hams, CW being a problem etc etc... In the March 96 issue of RAC there was a chart titled HAM LICENCES PASS 46,000 mark (in Canada). In 69/70 it was <12500 in 75/76 it was 15346 in 86/87 23063 now 46055 As you can see the number DOUBLED in 10 years. The growth rate is even higher in the 90/96 range and if continues like that will TRIPLE or QUADRUPLE by year 2006. Who are these people trying to fool? -- Madjid, VE2GMI From amsoft@epix.net Mon Jul 01 12:22:28 1996 Newsgroups: rec.radio.amateur.antenna From: Bob Lewis Subject: Re: rotatable dipoles Message-ID: <31D16533.766B@staffnet.com> Date: Wed, 26 Jun 1996 12:28:35 -0400 References: <4qkq6r$p5t@tribune.concentric.net> To: Dave Harrison Dave Harrison wrote: > > has anyone tried the cushcraft rotatable dipoles (trapped for 10-20m or > 10-40m)? Could I get away with mounting one on the side of my house just > below roof height (it's a 2 story)? I need to hide the antenna from the > neighbors (ccr's). Thanks, > please answer here or email me at 150.westside.com. I've used them on the side of a tower, work great. Try to keep it away from house as much as possible and especially away from metal gutters, etc. I have also made a rotable dipole from two HAMSTICK antennas (single band). Works pretty well also. From amsoft@epix.net Mon Jul 01 12:22:29 1996 From: jafl@msg.ti.com (Jim Flanders) Newsgroups: rec.radio.amateur.antenna Subject: Idea for antenna array at new QTH Date: 26 Jun 1996 14:40:10 GMT Message-ID: <4qri4a$s7q@ganesh.mc.ti.com> I moved the QTH to a house sitting on a small hill on the Texas Plains (Plano, TX). I am considering an antenna array, and am submitting it here for comments. Consider the overall design as four multiband (80-40-20-15-10) half slopers on a 65 foot mast. The length of each sloper is 48 ft. Each sloper slopes in a N-E-S-W direction respectively at a 50 degree angle. Not only the center conductor is switched individually for directivity, but also the outerconductor can be switched to any of the remaining slopers (thus effectively making a half wave inverted vee). Unused slopers are grounded to the mast, hopefully making them directors. Jim W0oog/5 14.243 @ 11:30 CST (subvets net) 147.180 (Plano repeater) From amsoft@epix.net Mon Jul 01 12:22:30 1996 From: jafl@msg.ti.com (Jim Flanders) Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Kenwood and Microsoft say ham radio dead Date: 26 Jun 1996 14:59:21 GMT Message-ID: <4qrj89$s7q@ganesh.mc.ti.com> References: <31C618E5.3567@ix.netcom.com> <1996Jun20.133842.10513@ke4zv.atl.ga.us> <31CBCD4B.751C@ccsnet.com> <4qk11t$aom@news0-alterdial.uu.net> I Never thought of it that way. Maybe you've hit it - when all the CB types leave for the internet, the seriouse Die-hards will get what is left. Now - if we can only work together. Jim W0oog/5 In article <4qk11t$aom@news0-alterdial.uu.net>, rpfox19@mailr.starnetinc.com says... > >This could actually be good news for the community. Infusion of the >Internet into our society may eliminate those who viewed amatuer radio >as another form of CB. Once that crowd leaves the airways amatuer >radio may return to the civil, and critical, service it was intended >to be. > From amsoft@epix.net Mon Jul 01 12:22:31 1996 From: n7oo@azgate.nj7p.ampr.ORG (Jack Taylor) Newsgroups: rec.radio.amateur.antenna Subject: Re: BALUN needed on stacked J-pole Date: 26 Jun 96 15:25:03 GMT Message-ID: <6584@NJ7P> I built a gain j-pole awhile back out of #12 solid copper wire. Using the parallel conductor impedance formula gave me an approximation of the spacing between the two conductors needed to give a 1:1 match at the resonant frequency. In my case it was something like 1/2 inch or so for 50 ohms. I found adding a 4:1 balun (made from RG-58) helped with both reducing the 'hand effect' (watching the SWR vary as you move your hand up and down the outside of the coaxial feedline), as well as providing an easier feedline match. 73 de Jack From amsoft@epix.net Mon Jul 01 12:22:32 1996 From: n7oo@azgate.nj7p.ampr.ORG (Jack Taylor) Newsgroups: rec.radio.amateur.antenna Subject: Re: BALUN needed on stacked J-pole Date: 26 Jun 96 16:01:16 GMT Message-ID: <6586@NJ7P> Recently I put together a gain J-pole made from #12 wire. In noting some articles discussing being able to only get a close match, I used the formula for parallel conductors to get an approximation of the spacing between the 'J' and the antenna element for 50 ohms. In my case it was around 1/2 inch. The thinking here was that the spacing would then allow a flat 1:1 match at the desired frequency. Indeed, this was found to be true. When attempting to match the "J" directly to the 50 ohm feedline there was a point near the shorted end where it was 1:1. However 'hand effect' was noticed. When watching the SWR meter there was a variation as the hand was moved along the outside of the coaxial feedline. This was not deemed desirable. A 1:1 BALUN was constructed which did eliminate the hand effect. But in my case it was difficult to mechanically get a precise 1:1 match due to the very limited range that this occured. A 4:1 BALUN made from RG-58 was found to give a less sensitive matching adjustment range as well as taking care of the hand effect. 73 de Jack From amsoft@epix.net Mon Jul 01 12:22:33 1996 From: drgrant@zipnet.net (Mike Capone) Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Kenwood and Microsoft say ham radio dead Date: Wed, 26 Jun 1996 16:09:46 GMT Message-ID: <31d15f89.2582395@news.zipnet.net> References: <31C618E5.3567@ix.netcom.com> <1996Jun20.133842.10513@ke4zv.atl.ga.us> <31CBCD4B.751C@ccsnet.com> On Sat, 22 Jun 1996 06:39:07 -0400, Burt Fisher wrote: :Kenwood and Microsoft agree ham radio is dying. :(but I told you that a long time ago) : :KENWOOD DEFENDS DISTRIBUTION PLANS : :Kenwood Communications Corp says its recently announced plans to make its :products available in more retail outlets will help to rejuvenate ham radio. :Citing concerns about the future of Amateur Radio and a changing business :climate, Kenwood announced it was taking "some bold steps" to revamp its :wholesale distribution scheme. : So what else is new? Kenwood rigs have been showing up at truck stops (CB shops, no?) :In a June 10 open letter to the Amateur Radio community, Kenwood's :Amateur Radio Products Group National Sales Manager Paul Middleton, :KD6NUH, painted a dismal picture. "When we looked at where Amateur Radio :is today, and where it is going to be in ten years at the present rate :of decline, the future looks bleak," he wrote, citing competition from :unlicensed communications modes. (internet). : Whoever here would compare ham radio to the internet needs their head checked. Like trying to compare an geo metro with a pickup truck. : "It is also obvious that the rate of no-code licensees is slowing down :with fewer and fewer people upgrading," Middleton wrote. "Amateur Radio :dealers should be more interested in attracting new people to our hobby. :Every current amateur operator who wants this hobby to continue should :be promoting ham radio to non-hams." : There's NO use whatsoever to promote ham radio to people who don't have any remote interest in it, it never sticks. Even if they do pass the TNC test, th ey rarely use their equipment. (A 30 day fad for some people) :* Microsoft Network (MSN) has dropped its Amateur Radio Forum, reports the :unofficial forum manager Rick McMillion, WB7UGZ. He said MSN gave him the :word recently in a terse e-mail message. McMillion says he had no warning :that MSN was going to dump the forum. MSN probably dumped it due to lack of activity in the forum. From amsoft@epix.net Mon Jul 01 12:22:34 1996 From: Ron Notarius WN3VAW <76336.2175@CompuServe.COM> Newsgroups: rec.radio.amateur.antenna Subject: Re: Butternut HF6V Vertical: Opinions? Date: 26 Jun 1996 16:37:27 GMT Message-ID: <4qrp07$oln$1@mhadg.production.compuserve.com> References: <960619204416_138681690@emout12.mail.aol.com> I've owned both an HF6V & an HF2V for over 10 years. Outside of weather effects over that long a period of time, I've never had an operational problem with either antenna (and I've had them both roof & ground mounted). Any problems I've had ended up being either user error(s) or coax problems (for example, I used some leftover 9913 when I installed the HF6 last year, and the effects of the winter & spring rains have ruined the coax -- but not the antenna). Highly reccomend these verticals for those looking for a good, solid performer. And they're a light lighter & easier to construct than the GAPs, which are otherwise decent verticals too. -- ron notarius wn3vaw my designated driver is a 12BY7A From amsoft@epix.net Mon Jul 01 12:22:35 1996 From: jjmartin@shore.net (Jim Martin) Newsgroups: rec.radio.amateur.antenna Subject: Re: Mobile antennas in thunderstorms? Date: Wed, 26 Jun 1996 16:57:08 GMT Message-ID: <4qrfjh$fv@shore.shore.net> References: <4q6pkj$ekg@news.rain.org> <31CA7F42.1DBD@staffnet.com> <4qecm5$e0q@newsstand.cit.cornell.edu> <4qi6dn$8uh@news-old.tiac.net> Reply-To: jjmartin@shore.net tsmith@fibusa.com (Tim Smith) wrote: >Also known in some circles as the "skin effect". Safest way to avoid >lightning strikes is to stay at home and watch weather channel.... Good advice Tim. I was stationed at Patrick Air Force Base in Cocoa Beach, Florida doing just that when lightning hit the cable. Took out my TV set along with many of my neighbors' sets too. Go figure. In 1993 I was living in Alamogordo, New Mexico. Coming back to Alamogordo from Las Cruces one day we had to go right into a T-Storm. It was doing this cloud to ground stuff all around us. I suggested to my wife and kids that they not to touch any metal parts of the vehicle. With the AM broadcast radio on you could hear the lightning charging up followed by a loud CRACK! it would discharge. Was a neat experience...and did no damage to my receiver or my two meter radio...then again a couple of weeks later a tiny static discharge on a cool dry day took out three stages of my IC-25H's receiver. We were listening to the space shuttle as they passed just over the horizon. I should have sold the radio then, after purchasing the last pieces of one of the parts that Icom had for it. Ahhhh....I still have it and it's working fine. I've even been online during many thunderstorms when@#$$!@#$%@(@$@( CARRIER LOST---- NOT! =========================================== cheers! jim martin, wk1v lowell, mass http://www.shore.net/~jjmartin/jjm.htm From amsoft@epix.net Mon Jul 01 12:22:36 1996 From: jjmartin@shore.net (Jim Martin) Newsgroups: rec.radio.amateur.antenna Subject: Re: Sliced bread! Date: Wed, 26 Jun 1996 17:00:42 GMT Message-ID: <4qrfq7$fv@shore.shore.net> References: <4qnifs$h8q@news-old.tiac.net> Reply-To: jjmartin@shore.net tsmith@fibusa.com (Tim Smith) wrote: >Hi fellow antenna tweakers. I just brought home my nifty new MFJ-259 SWR >analyzer last week and man...it's the best thing since sliced bread! No >more dragging out the rig, feedline and tools to the picnic table...just take >the analyzer right to the antenna and do all you tweaking right there! No >only does it give you an indication of minimum reflected power but also give >you a relative measurement of load impeadance (with respect to a 50 phm sourc e >impedance). >I've always liked building and playing with antennas but with a box like this >it's actually fun! I'd recommend it to anyone. My thoughts too Tim when I purchased mine about six months ago. I tuned every antenna I had around the house the first night I had it. What do you do with it after that?? hehehe It comes in very handy for tuning the transmatch off the air. And comes in handy for making it difficult for my neighbor to hear incoming signals when he is operating on 27.575.....I don't have to listen to him coming through my scanner or telephone....it's like remote shutdown. He's that close. =========================================== cheers! jim martin, wk1v lowell, mass http://www.shore.net/~jjmartin/jjm.htm From amsoft@epix.net Mon Jul 01 12:22:38 1996 From: mowery@alpha.shianet.ORG (Mark and Beth Mowery) Newsgroups: rec.radio.amateur.antenna Subject: Backstay as ham antenna Date: 26 Jun 96 19:02:33 GMT Message-ID: <31D18949.46D1@shianet.org> Here's one for all the sailing hams out there. I've been using an Outbacker on my sailboat with good results, but would like to isolate and feed my backstay, using an automatic tuner. My idea was to run the coax up through the mast and exit at the top, connecting the center conductor to the i solated portion, and the ground braid to the mast at the top for use as a counterpoise . The mast is grounded through a short length of tinned copper braid from the compre ssion post to a keelbolt in the bilge, and then to the water through two 12" square bronze plates bolted to either side of the fin. My questions are this: 1) Will there be enough of an advantage to feeding the stay at the top to outw eigh the extra effort required? It would be much easier to feed at the bottom (shorter coax run, no fishing wires through the mast, easier access to feed point). 2) What's a good way to actually attach the coax and make it somewhat weatherp roof? Are there commercial parts available for just this purpose? I'm in the Great L akes so saltwater obviously isn't a problem, but as long as I'm doing it I want to do it right. 3) Any recommendations on specific parts, such as backstay insulators, or any other comments on the project are welcomed. I am open to any and all suggestio ns and comments. Please reply directly to me: mowery@shianet.org, if interest is high I will post the results to the list for everyone to see. Thanks in advance, and to the hams: 73 Mark AA8TC S/V Gazelle Lake Huron From amsoft@epix.net Mon Jul 01 12:22:39 1996 Newsgroups: rec.radio.amateur.antenna From: "David E. Shelton" Subject: Horizontal Loop in Triangle configuration. Message-ID: <31D19317.3888@iglou.com> Date: Wed, 26 Jun 1996 19:44:23 GMT I am getting ready to setup a 40M horizontal loop in the backyard. I have a small place and since the wife is not going to allow a tower at this QTH I am going to put up this loop until I figure out something else. I can only put it up in a Triangle configuration and the performance is what I needed input on. How well will a triangle configured loop work and what if the angles of the triangle are not all equal? Any input greatly appreciated! 73, de KE4FPS, David ke4fps@iglou.com From amsoft@epix.net Mon Jul 01 12:22:40 1996 Newsgroups: rec.radio.amateur.antenna From: Bob Lewis Subject: Re: Is a Balun Necessary? Message-ID: <31D1DF35.77AF@staffnet.com> Date: Wed, 26 Jun 1996 21:09:09 -0400 References: <4qcvro$f3j@alterdial.UU.NET> <4qf89f$30u@itnews.sc.intel.com> Cecil Moore wrote: > > Gareth Crispell wrote: > >I am going to put up a yagi monobander and am wondering if a 1:1 is at > >all necessary? Any and all opinions will be appreciated. > > Without a balun, you will get some feedline radiation and a skewed > radiation pattern. Either effect may or may not be neglible. > > 73, Cecil, W6RCA, OOTC (not speaking for my employer) You can wind a coaxial choke with about 10 turns, 8" dia. with your coax in order to minimize feedline radiation. Be careful with baluns. If you overdrive them or run a high SWR they can cause more problems than they correct - especially ferrite core baluns. From amsoft@epix.net Mon Jul 01 12:22:41 1996 From: bshaw@connect.net (Bradley Shaw) Newsgroups: rec.radio.amateur.antenna Subject: COMET GP15 Date: Wed, 26 Jun 96 21:20:29 GMT Message-ID: <4qsd19$dif@dallas1.connect.net> Say does anyone know anything about the Comet GP15? From amsoft@epix.net Mon Jul 01 12:22:42 1996 From: Jake Brodsky Newsgroups: rec.radio.amateur.antenna Subject: Re: Buried radials: Insulated or bare? Date: Wed, 26 Jun 1996 22:10:00 -0700 Message-ID: <31D217A8.4709@erols.com> References: <4qlqep$5j6@doc.zippo.com> S.Y.Stroobandt@e-eng.hull.ac.uk wrote: > Can anybody tell me what is best: insulated or buried radials? > > My guess is that the performance level of both should be about the same, > except that insulated radials will last longer. My intuition says you're on the right track. Just make sure the insulation is appropriate for direct burial (ie. water-proof). 73, Jake Brodsky, AB3A "Beware of the massive impossible!" From amsoft@epix.net Mon Jul 01 12:22:43 1996 From: gary Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc Subject: Re: Kenwood and Microsoft say ham radio dead Date: 26 Jun 1996 22:26:13 GMT Message-ID: <4qsde5$d0@chewy.castles.com> References: <31C618E5.3567@ix.netcom.com> <1996Jun20.133842.10513@ke4zv.atl.ga.us> <31CBCD4B.751C@ccsnet.com> <4qk11t$aom@news0-alterdial.uu.net> <31CDB78E.5A53@ccsnet.com> Burt Fisher wrote: >Bob Fox wrote: >> >> This could actually be good news for the community. Infusion of the >> Internet into our society may eliminate those who viewed amatuer radio >> as another form of CB. Once that crowd leaves the airways amatuer >> radio may return to the civil, and critical, service it was intended >> to be. > >Once that crowd leaves hardly anyone will be left except the >dead and dying. > >#================#=====================================================# >| Burt Fisher | Teacher of video, broadcasting and electronics | >| Amateur call | South Dennis, Ma. (Cape Cod) | >| K1OIK | The less you say, the more people will remember | >#================#=====================================================# >| k1oik@ccsnet.com | >#======================================================================# > >http://www.qrz.com/cgi-bin/qrz_gifs?k1oik.gif HO HO HO.... God, I *HATE* it when you're RIGHT! -- Gary....KJ6Q *** I AM THE NRA! *** "The NRA doesn't vote, it's *MEMBERS* do - *ABUNDANTLY!*" From amsoft@epix.net Mon Jul 01 12:22:44 1996 From: pdrunen@aol.com (PDRUNEN) Newsgroups: rec.radio.amateur.antenna Subject: Re: Kenwood and Microsoft say ham radio dead Date: 26 Jun 1996 23:16:43 -0400 Message-ID: <4qsuer$bpq@newsbf02.news.aol.com> >There's NO use whatsoever to promote ham radio to people who don't have any >remote interest in it, it never sticks. Even if they do pass the TNC test, they >rarely use their equipment. (A 30 day fad for some people) I know an engineering friend that when all the way to Extra in less than 4 months! I recommended a ham HF rig to him which he ordered, and I helped him order it. after he got it, he spent his whole weekend finding every fault. Things like the scan feature did not tune in the SSB when it found an SSB signal and there were a few birdies outside the ham band etc. etc. I will leave the antenna tuner to another story. After he got his extra ticket he went off into computer land and I don't suggest rigs to engineering types anymore!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Let's enjoy the hobby not find faults in it - Want a super rig then get a super wallet! From amsoft@epix.net Mon Jul 01 12:22:45 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Growth Rate is UP not down! Date: 26 Jun 1996 23:47:15 -0400 Message-ID: <4qt083$cth@newsbf02.news.aol.com> References: <31D18366.4776@odyssee.net> In article <31D18366.4776@odyssee.net>, Madjid writes: >As you can see the number DOUBLED in 10 years. The growth rate is even >higher in the 90/96 range and if continues like that will TRIPLE or >QUADRUPLE by year 2006. > >Who are these people trying to fool? > >-- >Madjid, VE2GMI > > Hi Madjid, That's interesting. My memory may be flawed, but as I recall when I looked at amateurs as a percentage of the US population when the ARRL and others were whining about there not being enough Hams, the percentage was higher than ever. Sounds like someone tried to create a political justification for no code. The reason I slacked off on operating is the lack of intelligent QSO's. The bulk of my contacts are ragchews on CW now, especially when mobile. I get bored with exchanging reports and talking about the weather. I get offended by people using terms like having "beams on the flat side" and being "on the side". It sounds like CB banter. 73 Tom From amsoft@epix.net Mon Jul 01 12:22:46 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Growth Rate is UP not down! Date: 26 Jun 1996 23:49:20 -0400 Message-ID: <4qt0c0$cvj@newsbf02.news.aol.com> References: <31D18366.4776@odyssee.net> In article <31D18366.4776@odyssee.net>, Madjid writes: >As you can see the number DOUBLED in 10 years. The growth rate is even >higher in the 90/96 range and if continues like that will TRIPLE or >QUADRUPLE by year 2006. > >Who are these people trying to fool? > >-- >Madjid, VE2GMI > > Hi Madjid, That's interesting. My memory may be flawed, but as I recall when I looked at amateurs as a percentage of the US population when the ARRL and others were whining about there not being enough Hams, the percentage was higher than ever. Sounds like someone tried to create a political justification for no code. The reason I slacked off on operating is the lack of intelligent QSO's. The bulk of my contacts are ragchews on CW now, especially when mobile. I get bored with exchanging reports and talking about the weather. I get offended by people using terms like having "beams on the flat side" and being "on the side". It sounds like CB banter. 73 Tom From amsoft@epix.net Mon Jul 01 12:22:47 1996 From: Jake Brodsky Newsgroups: rec.radio.amateur.antenna Subject: Re: Toroidal Helical Antenna --- Revolutionary New Antenna Date: Thu, 27 Jun 1996 00:22:35 -0700 Message-ID: <31D236BB.23BB@erols.com> References: <4qgrdm$crk@newsbf02.news.aol.com> <4qpdr3$ip9@newsbf02.news.aol.com> Ok, we've beat up these guys enough now. The real question: For the size they have made the silly thing, is it any more efficient or widebanded than, say, a shortened loop of the same size? Jake Brodsky, AB3A "Beware of the massive impossible!" From amsoft@epix.net Mon Jul 01 12:22:47 1996 From: cbaldwin@mailhost2.csusm.edu (Christopher Baldwin) Newsgroups: rec.radio.amateur.antenna Subject: Looking for plans on 222MHZ antenna Date: 27 Jun 1996 00:31:25 GMT Message-ID: <4qskot$n44@bobcat.csusm.edu> I've got a length of RG213 and lots of PVC Pipe. Anyone tell me how to turn it into a halfway decent 222MHz antenna? Please EMAIL me Chris From amsoft@epix.net Mon Jul 01 12:22:48 1996 From: "Thomas W. Castle" Newsgroups: rec.radio.amateur.antenna Subject: Diamond vs Comet Ant. Date: Thu, 27 Jun 1996 03:07:32 -0400 Message-ID: Hi Tom here... Somewhere in the past 6 months, I followed a thread of a message about the Diamond an Comet Antennas. It was based on the Diamond 500HNX antenna an its Comet counterpart... Both basically dual band 2mtr/70ctmr high gain antennas' for base/repeater use. In this thread was a person reportedly works for Comet , said theirs was "better" because they "Didn't" us phasing caps but used tunned stubs for phasing the various sections an were DC grounded... Yet I can't find this or similar info from Comet about their antenna.... The reason I am interested in a high gain but more of a safer antenna, is because I have just replaced my 2 Diamond 500HNX after being hit by lightenning... They turn into Tiny whisk brooms an 10,000 little pieces, I am getting tired of this... Any Ideas gang??? They where up at 50' to 90' when they where hit. Tower is well grounded. An they are the only antenna being hit...? Tnx De Tom From amsoft@epix.net Mon Jul 01 12:22:49 1996 From: pogletre@mail.coin.missouri.EDU (Perry W. Ogletree) Newsgroups: rec.radio.amateur.antenna Subject: Re: Fwd: LHJ Date: 27 Jun 96 04:47:43 GMT Message-ID: <199606270447.XAA24581@coins0.coin.missouri.edu> This is old news. The ARRL has met with the publishers and is helping them draft a retraction for future publication. 73 de Perry N0NMC From amsoft@epix.net Mon Jul 01 12:22:50 1996 From: agurney@hpsqf.sqf.hp.com (Alisdair Gurney) Newsgroups: rec.radio.amateur.antenna Subject: Meteosat Yagi Date: 27 Jun 1996 10:52:28 GMT Distribution: world Message-ID: <4qtp5c$6i6@hpwin055.uksr.hp.com> Does anyone have any suggestions/plans for a yagi suitable for receiving Meteosat transmissions? Maplin Electronics used to sell a yagi with their downconverter and WSAT decoder, but it has long since been discontinued. Information please, to alisdair@agurney.demon.co.uk Alisdair Gurney From amsoft@epix.net Mon Jul 01 12:22:51 1996 From: n1ddzrjc@aol.com (N1DDZ RJC) Newsgroups: rec.radio.amateur.antenna Subject: Facts needed: 9913 vs Times Date: 27 Jun 1996 11:03:56 -0400 Message-ID: <4qu7ss$p1g@newsbf02.news.aol.com> Reply-To: n1ddzrjc@aol.com (N1DDZ RJC) There appears to be lots of hype about the relative loss and flexibility characteristics of the so-called 9913 class of cable offered by various manufacturers. I'm replacing my 11 feedlines this summer. That means I am about to spend somewhere between $600 and $900 for coax. There are ads for a Times wire and cable "equivalant" to 9913 that claims: Non-hosing about -3.2dB/100' @450 MHz Flexible center conductor about $0.75/foot Takes an N connector or a PL-259 "well". Non-conatminating jacket. Anyone with verifiable test info on these cables? Particularly interested in service life experience and tests of these types of cables AFTER installation and use for 1+ year. Bob From amsoft@epix.net Mon Jul 01 12:22:52 1996 From: rpmackin@ashley.ivey.uwo.ca (Robert Patrick MacKinnon) Newsgroups: rec.radio.amateur.antenna Subject: Help: need S-Band antenna (2.5-2.7 GHz) Date: 27 Jun 1996 11:45:30 GMT Message-ID: <4qts8q$2lu@falcon.ccs.uwo.ca> I have an S band downconverter that wants to be fed via an N connector. Could anyone please offer suggestions on the best antenna to connect to it? My interestes are both TVRO and well as terrestrial. tnx de VE3PMK Pat MacKinnon, London Ontario. Tel: 519 649-1455 Fax: 519 649-7776 From amsoft@epix.net Mon Jul 01 12:22:54 1996 Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc From: gary@ke4zv.atl.ga.us (Gary Coffman) Subject: Re: Kenwood and Microsoft say ham radio dead Message-ID: <1996Jun27.132430.13406@ke4zv.atl.ga.us> Reply-To: gary@ke4zv.atl.ga.us (Gary Coffman) References: <1996Jun20.133842.10513@ke4zv.atl.ga.us> <31CBCD4B.751C@ccsnet.com> <31CDE35E.4882@odyssee.net> <4qm254$3l7@lehi.kuentos.guam.net> <4qpdm2$89k@huron.eel.ufl.edu> <4qr7fs$lep@lehi.kuentos.guam.net> Date: Thu, 27 Jun 1996 13:24:30 GMT In article <4qr7fs$lep@lehi.kuentos.guam.net> pacrimgolf@kuentos.guam.net writ es: >John Hughes wrote: >>pacrimgolf@kuentos.guam.net (Jim Kehler) wrote: >>> Make it ICOM or TEN-TEC. Vote with your wallet and your brain. >>> 73, Jim KH2D >>Well, fill me in. What's your objection to Yaesu...nationalistic? > >Nope, nobody here makes radios, and the big three are all made >in the same nation. Icom's HF receivers are far superior to Kenwoods, >that's why all the big contesters use Kenwood. The deader your >receiver, the less you hear the guy's transmitter who is sitting >next to you. Yaesu has had problems ever since the invention of >the transistor - they made fairly good stuff when we all used tubes, >but since then they have gone down hill dramatically. And Yaesu's >target market has always been 11 meters. After the 101's they >took 11 off the bandswitch, but they replaced it with a dipswitch >inside the radio, I guess so nobody would cut the wrong wire..... I suspect you'll get a lot of argument about your comments above. Though I own Icom HF equipment, an IC-735 and an IC-706, I must say that Icom is in second place for HF transceivers compared to the newer Yaesus. At the top of the line, the FT-1000 simply blows Icom and Kenwoood away, and the FT-990 and FT-900 aren't bad in their price classes either. Kenwood HF gear is also pretty good, if you can keep it working. The big problem with all the recent Kenwood gear is reliability. (And their VHF/UHF gear has always sucked.) >I did see a Icom 706 (?) at field day last weekend, and I wasn't real >impressed with the receiver (HF) on it, it has the image problem on >CW that the 745 had. But it's a whole lot of bands for not a whole lot >of money, so it still looks like a good deal to me. It is a good deal, for what it is. It is not a top of the line rig, though I must take issue with comparing it to the IC-745. Now that was a truly awful radio. It suffered even more from front end overload (all the time) than the IC-706 does when the IC-706 preamp is on (you should leave the preamp off on HF, you never need it). The IC-706 does let you reverse sidebands in CW mode, which does get rid of most problems. There is a bit of filter blowby (I assume the rig you saw was fitted with the optional CW filter, without it the IC-706 is totally unsuitable for CW or digital), but it isn't nearly as bad as the old IC-745. That thing was a real turkey. The IC-706 isn't as good as the IC-735, but then few radios are (and all of those are lots bigger and cost lots more), and the IC-706 is smaller still, and does offer 6m and 2m. >My observations are not based on labratory testing (Gary can fill you >in on that), just real world use. After having owned radios from all >of the big three, and having watched all the guys I started out with >do the same, seems like most if not all of us wound up with boxes >that say Icom on the front. In the last ten years I've also met a >lot of Japanese hams, and most I've met prefer Icom also. Like I mentioned, I've got two Icom radios now, but I've owned Kenwood, Yaesu, Ten-Tec, Drake, National, Hallicrafters, Heath, SBE, Galaxy, Johnson, B&W, Collins, etc over the years. The Icom radios aren't the absolute best in raw performance. Of all those I mentioned, the FT-1000 is the best in raw performance. But there are more issues than that for me. I want a small radio today, and I want one that is well built mechanically and thermally. In the small radio class, that's Icom. But if I were fielding a big contest station, all the radios would likely say Yaesu on the front. Though if I could keep them running, they might say Ten-Tec (you *need* that great factory support). They would not say Kenwood unless I had at least four sets of spare radios. That way maybe I'd have one radio that worked when I needed it. Gary -- Gary Coffman KE4ZV | You make it, | Due to provider problems Destructive Testing Systems | we break it. | with previous uucp address es 534 Shannon Way | Guaranteed! | Email to ke4zv@radio.org Lawrenceville, GA 30244 | | From amsoft@epix.net Mon Jul 01 12:22:54 1996 From: Dave_Covert@msn.com (David Covert) Subject: RE: 10 meter antenna questions..... Date: 27 Jun 96 13:46:51 -0700 References: <8C2E55C.0407000A7B.uuout@cheaha.com> Message-ID: <00001fea+0000236b@msn.com> Newsgroups: rec.radio.amateur.antenna Just so you know... this past Saturday (Field Day) I ran the Novice station at the club field day site (near Dallas). In 24 hours, I made 212 contacts on 10m with a FT-840 running 100w into a ~50ft dipole strung between trees at a 1:1.1 match. I was getting reports from Calf and Florida stating that I was 'booming' in there. We made contacts on 10m all the way up to midnight. I am thinking that 10m is dead because everyone says it is and no one is trying. Try calling CQ on 10m a little more often... I think we would all be suprised... 73, Dave Covert, KB5GOG From amsoft@epix.net Mon Jul 01 12:22:55 1996 From: cliffd@zetnet.co.uk (Cliff Davies) Newsgroups: rec.radio.amateur.antenna Subject: Re: How do I attach an HF antenna to a Honda? Date: Thu, 27 Jun 1996 16:20:31 +0100 Message-ID: <4r0fts$jv6@roch.zetnet.co.uk> References: <4qqtl9$gja@masters0.Internex.NET> In message <4qqtl9$gja@masters0.Internex.NET> andy@pythagoras.org (Andy Nourse) writes: > I have a Honda Civic hatchback and have found a notable lack of places to > attach antennas. Most other relatively new cars seem to be this way too. I found the following worked OK for me, Try using a piece of flat plate about 1 and a half inches wide (and in my case 16" long) and a 90deg 'twist', bolt this to the 'Towing eye' underneath at the back, this can be angled to appear just under the bumper and then cut 'n drill to suit, From amsoft@epix.net Mon Jul 01 12:22:56 1996 From: mwalkdba@ezl.com (Mark Walker) Newsgroups: rec.radio.amateur.antenna Subject: Re: Horizontal Loop in Triangle configuration. Date: Thu, 27 Jun 1996 20:20:25 GMT Message-ID: <4quq2g$90a@ns1.ccinet.net> References: <31D19317.3888@iglou.com> "David E. Shelton" wrote: {snip} IMHO, no dipole at ANY height will perform as well as even a sloppily-built loop. I used a square 75M loop for years, and am now forced into the very triangle configuration you are pondering. Fed directly with coax, it is an equilateral triangle with 2 corners at the back of the yard at about 18 feet, and the apex attached to a 6-foot roof tower on my ranch house. The new loop is quite a bit smaller than the old one, and the bandwidth on 160 and 75 is somewhat narrow. However, it is still a very quiet antenna, and seems to perform quite well on 20 in particular. I usually run between 100-200 watts, haven't had much operating time lately due to back surgery, but I'd be more than happy to show you my log during this time of "dead" bands. May 1990 QST has an excellent article showing E and H plane diagrams for loops used at exceptionally LOW heights. A loop at low heights shows VERY strong low-angle lobes on 20/15/10. I would have no other antenna short of monobanders at 100 feet. Let me know if you want details. From amsoft@epix.net Mon Jul 01 12:22:57 1996 From: "Bill Wilson" Newsgroups: rec.radio.amateur.antenna Subject: Re: Facts needed: 9913 vs Times Date: Thu, 27 Jun 1996 22:01:32 -0700 Message-ID: <01bb64af.739ddac0$36111dcc@bwilson.halcyon.com> References: <4qu7ss$p1g@newsbf02.news.aol.com> This reply is just hearsay.... The Times and the new Andrew braided coax equivalent to the Times are supposed to be equal to each other and both are supposed to be better than the Belden for outdoor use. Good Luck Bill > n1ddzrjc@aol.com (N1DDZ RJC) wrote in article <4qu7ss$p1g@newsbf02.news.aol.com>... > There appears to be lots of hype about the relative loss and flexibility > characteristics of the so-called 9913 class of cable offered by various > manufacturers. > > I'm replacing my 11 feedlines this summer. That means I am about to spend > somewhere between $600 and $900 for coax. There are ads for a Times wire > and cable "equivalant" to 9913 that claims: > > Non-hosing > about -3.2dB/100' @450 MHz > Flexible center conductor > about $0.75/foot > Takes an N connector or a PL-259 "well". > Non-conatminating jacket. > > Anyone with verifiable test info on these cables? Particularly interested > in service life experience and tests of these types of cables AFTER > installation and use for 1+ year. > > Bob > From amsoft@epix.net Mon Jul 01 12:23:00 1996 Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment From: charles1@netcom.com (charles copeland) Subject: Re: Antenna Driving me nuts Message-ID: References: <4qsk9b$s84@news.inforamp.net> Date: Thu, 27 Jun 1996 22:16:22 GMT In article <4qsk9b$s84@news.inforamp.net>, Chris Valliant wrote: > > > I have been trying for the last two weeks to build a half wave >diapole antenna. I have read the book twice, done my calculations down to >the half inch, used several different gauges of wire, several makes of >coax cable but I cannot get the SWR reading below 6:1. Even with an >antenna tuner I cannot get an acceptable SWR reading. It's driving me to >the funny farm. I have about a mile of wire in my apartment and have run >out of ideas. Here is what I am trying to do: to build a 1/2 wave >diapole for the 28-29 mhz. I splice the coax, solder one end to a length >of wire 8.2 feet and the other braided end to a length of wire the same >size. I suspend both ends using insulated clamps between two tree's, >making sure that the whole antenna is parallel to the ground and it's 8 >feet above the ground. Now when I check the SWR, it's unbelieveable. Like >I have said before, I have used different wire, different coax (the >standard coax, just different brands). What am I doing wrong ? Can anyone > spot my mistake ? I will gladly make it up to whomever spots my error. >Anyway, thanks for listening. Swtich from coax to twin lead. You can buy ladder line from ham shop or just use TV antenna twin lead wire. Feed it into your balance line input to the tuner. I had the same type of problems with SWR till I did this on my dipole. From amsoft@epix.net Mon Jul 01 12:23:00 1996 From: cbreaux367@aol.com (CBreaux367) Newsgroups: rec.radio.amateur.antenna Subject: 2m Yagi/Diagram Needed Date: 28 Jun 1996 02:54:33 -0400 Message-ID: <4qvvj9$j5r@newsbf02.news.aol.com> i'm in need of a diagram depicting a multielement (@least 10 element) beam with appropriate dimensions and delta or gamma matching array. i've looked in the arrl antenna book and have found numbers but no diagram. if you're out there with the perfect information please respond. THANKS! 73 HamRadio From amsoft@epix.net Mon Jul 01 12:23:02 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Toroidal Helical Antenna --- Revolutionary New Antenna Date: 28 Jun 1996 03:48:38 -0400 Message-ID: <4r02om$k48@newsbf02.news.aol.com> References: <31D29B9F.65A3@netaxs.com> In article <31D29B9F.65A3@netaxs.com>, "C.D.Sage" writes: >Mr.Brodsky, > >You boys in the antenna fraternity really have a way with words. :-) If you >could on >occasion include a translation in your posts for those of us less well >endowed it would >be mighty neighborly of you.By the way, I certainly appreciate you all taking >the time >to look at the THA.- Thanks.- > >- Clem Sage - >( P.S.) > You all wouldn't be interested in a membership in the Flat Earth Society >would ya. ;-) Hi Clem, From your ending comment, it seems you must be a believer in the THA. Unfortunately, it must conform to every rule that applies to any antenna ever built...or the rules are all wrong. From you comment, you must believe the THA offers a revelation in electromagnetics, one as earth shaking as the discovery the earth is (almost) round. Since EVERY antenna ever built to this day (that includes spirals and helices..and even verticals and multielement driven arrays used in deep space listening) conforms to the rules we use, I find it pretty hard to believe the rules are wrong. We aren't talking about the cutting edge of exploration, we're talking about a simple antenna (the shape and construction of which has been used hundreds and thousands of times) in the middle of established rules that dozens of more complex antennas follow to the letter. The "world is flat" equivalent would, more appropriately, be discovery the world really is flat, the helical toroidal antenna really works, and Elvis is still alive. In the most basic term, electromagnetic radiation occurs because electrons accelerate. If you visualize the outside world's view of the electron movement in the antenna, you can form a mental picture of how easily and effectively an antenna radiates. The more "wasted" movement of electrons, the less efficient the antenna will be. The harder it is to "see" electrons accelerating over a large distance, the more electrons we'd have to move to generate a given field strength. Visualize the current in a dipole. Standing broadside, we see all the electrons moving in unison for a long distance. From the end view, we hardly see anything move. Just like looking at the blades of a fan, from the edge view we only see something happening up close. Looking into the flat side, we plainly see and feel the effects of the movement. All the toroidal helical antenna does is waste a lot of electron movement. The net radiating apature is the same as a convenional single turn loop the same size, with addition of many useless and lossy loop de loops. Loops come towards us, and a equal number go away. The net radiating effect of the small loops is zero. Radiation comes mainly from the movement around the larger circle, but we accomplished that electron movement through all the wasted small loops. Every useless small loop adds loss resistance, and makes the system work harder to produce the same electromagnetic field. There is no doubt the THA won't work near as well a properly constructed single turn loop the same size. Revolutionary antenna's pop up all the time. The cross field antenna, the Uni-hat, the Maltese quad, a two turn magnetic loop in the Antenna Compendium, insulated and elevated radials. They have two things in common, they promise something for nothing and they never quite get proven in independent real world tests. 73 Tom From amsoft@epix.net Mon Jul 01 12:23:03 1996 From: gelleric@kafka.informatik.uni-stuttgart.de (Wolfgang Gellerich) Newsgroups: rec.radio.amateur.antenna Subject: Re: Indoor HF antenna Date: 28 Jun 1996 08:41:57 GMT Distribution: world Message-ID: <4r05sl$t8h@zdi.informatik.uni-stuttgart.de> References: <31CC5E90.1074@lex.infi.net> In article <31CC5E90.1074@lex.infi.net>, "Aaron J. Welch" writes: |> Got a small problem... |> |> I recently moved into a 2 bedroom apartment, and I'm prohibited from putti ng any type of external |> antenna outside (tv, amateur, etc). I've got a Kenwood TS-130S rig, and I r eally hate to give up my HF |> work just because of my living conditions. I'm looking for some kind of ind oor antenna that will generally |> cover 80-10m (at least 80-20), and won't cost an arm and a leg. I know ther e are some indoor antennas on |> the commercial market, but most of those that I've seen are either way out of my price range, or they're just |> "too good to be true". I can handle just about any type of antenna (wire, c oax, etc). If you have any |> suggestions as to what I could do, please e-mail me. Any and all assistance is greatly appreciated. |> |> -73- de KE4ENO |> truant@lex.infi.net |> Try a magnetic loop ! They are rather small and they use only the magnetic component of the electromagnatic field -- in contrast to "normal" antennas that only receive/transmit the electric component. Since the attenuation of most materials including reinforced concrete to magnetic fields is much lower than to electric fields, magnetic loops also work quite well as indoor antenna. However, mags also have some problems. The bandwidth is very small, so you must tune them quite often. And, they suffer from a very low radiation resistance. The RR decreases with the fourth power of the wavelength and increases with the fourth power of the loop's diameter. So, an appartment-size antenna will probably cover 10..20m only. See the ARRL antenna book for details! vy 73, Wolfgang DJ3TZ From amsoft@epix.net Mon Jul 01 12:23:04 1996 From: graham@southlin.demon.co.uk (Graham Seale) Newsgroups: rec.radio.amateur.antenna Subject: Re: Toroidal Helical Antenna --- Revolutionary New Antenna Date: Fri, 28 Jun 1996 10:29:59 GMT Distribution: world Message-ID: <19960628.102959.73@southlin.demon.co.uk> References: <31D29B9F.65A3@netaxs.com> <4r02om$k48@newsbf02.news.aol.com> Reply-To: graham@southlin.demon.co.uk Hi there Tom (and Clem too) In message <4r02om$k48@newsbf02.news.aol.com> W8JI Tom wrote: > From your ending comment, it seems you must be a believer in the THA. > Unfortunately, it must conform to every rule that applies to any antenna > ever built...or the rules are all wrong. From your comment, you must > believe the THA offers a revelation in electromagnetics, one as earth > shaking as the discovery the earth is (almost) round. Since EVERY antenna > ever built to this day (that includes spirals and helices..and even > verticals and multielement driven arrays used in deep space listening) > conforms to the rules we use, I find it pretty hard to believe the rules > are wrong. The quote above confirms the spirit of what I separately tried to express for Clem. If ever there was a place where any new idea, however improbable, can be expressed, it is here! The price is .. it will be tested by the toughest most plain speaking peer group I know - this same community being renown for their fairness and good humour. The rules are simple. One may assert anything that has not seen a single exception in all accumulated experience, while a single verified exception is enough to trash the most revered rationale, without regard to the effect on reputations or product prospects. If an antenna can cut it among this company, then it likely has merit. Many in this group have access to the most advanced design tools anywhere, and there are few academic institutions where rec.amateur.radio.antenna does not have some readership. Keeping in mind that Clem is not a antenna expert, but more probably a potential investor researching a prospective venture, it was perhaps inevitable he should be startled by our norms. With hindsight, perhaps our first response to Clem's original posting was a bit terse. We should have been a bit more welcoming. He thought he was being treated like a hoaxer! Sorry for that Clem. I assure you there is no ill will here. 73's All G4WNT -- Graham Seale From amsoft@epix.net Mon Jul 01 12:23:05 1996 From: fedpress@omnifest.uwm.edu (Rick Kissell) Newsgroups: rec.radio.amateur.antenna Subject: Re: Answer to: What's a big wheel Date: 28 Jun 1996 12:27:59 -0500 Distribution: na Message-ID: <4r14mv$t3h@omnifest.uwm.edu> There is also information on Big Wheel antennas in "The Radio Amateur's VHF Manual" published some years ago by the ARRL. They are available commercially from the Olde Antenna Lab, 4725 W. Quincy Avenue, Denver, CO 80236. Phone (303) 798-5926. The chief eng. is Dave Clingerman, W6OAL. A year ago, he quoted me a price of $400 plus shipping for a 6m big wheel. Here are the prices in his catalog for big wheels for the other bands: 2m $150 shipped 222 $130 shipped 440 $50 shipped 900 $50 shipped 1250 $50 shipped 73, Rick WB9GYT Milwaukee From amsoft@epix.net Mon Jul 01 12:23:06 1996 From: pacrimgolf@kuentos.guam.net (Jim Kehler) Newsgroups: rec.radio.amateur.antenna Subject: Re: Dual Band Base Antenna...? Date: Fri, 28 Jun 1996 12:33:48 GMT Message-ID: <4r0mu0$mi6@lehi.kuentos.guam.net> References: <31C71F98.234B@polar.polarcomm.com> <4qtihq$8se@sjx-ixn6.ix.netcom.com> <01bb6490.bad4d840$1b0da8c0@af006.lafn.org> Reply-To: pacrimgolf@kuentos.guam.net "Harv Shore" wrote: >I am curious if Diamond and Comet are one in the same with a different >label Nope. Two different companies. In Japan, anyway. From amsoft@epix.net Mon Jul 01 12:23:07 1996 From: Kevin Muenzler Newsgroups: rec.radio.amateur.antenna Subject: Buried radials: Insulated or bare? Date: 28 Jun 1996 12:40:07 -0400 Message-ID: <19960628124004.aaaa005HV@babyblue.cs.yale.edu> Reply-To: wb5rue@amsat.org mravitz@ix.netcom.com (Mitchell Ravitz) wrote: -I remember reading somewhere that ground radials were more efficient -if they were above the ground. I may be wrong here, it was quite a -while ago. Anyone know? - -Mitch -WA1DTX The difference between above ground and below ground radials is really insignificant unless you have an extremely high mineral content and you put them more than several inches deep. Usually if you have a "lawn" you can place it just below the roots of the grass and not have any problem at all. I just took a flat shovel and cut through the grass runners and then pushed the wire into the cut. I guess the total depth is about 2 inches. I used insulated wire for longevity. The insulation doesn't effect the performance enough at HF to measure. I live in the sand so I could probably put them 2 feet down without any problems but just north of where I live there is clay soil that only a few inches deep would make a difference. Kevin, WB5RUE wb5rue@amsat.org From amsoft@epix.net Mon Jul 01 12:23:08 1996 Newsgroups: rec.radio.amateur.antenna From: Monty Wilson Subject: Re: How do I attach an HF antenna to a Honda? Message-ID: Date: Fri, 28 Jun 1996 12:58:41 GMT References: <4qqtl9$gja@masters0.Internex.NET> <1996Jun27.162745.567@nad.com> Duct tape? -- .........Monty. mwilson@flex.net From amsoft@epix.net Mon Jul 01 12:23:09 1996 From: cteclaw@clark.net (Charles Teclaw) Newsgroups: rec.radio.amateur.antenna Subject: Re: Horizontal Loop in Triangle configuration. Date: 28 Jun 1996 13:18:08 GMT Message-ID: <4r0m2g$oot@clarknet.clark.net> References: <31D19317.3888@iglou.com> <4qssm9$2evu@mule2.mindspring.com> david l. thompson (thompson@atl.mindspring.com) wrote: : "David E. Shelton" wrote: : : >I am getting ready to setup a 40M horizontal loop in the backyard. I have : >a small place and since the wife is not going to allow a tower at this : >QTH I am going to put up this loop until I figure out something else. I : >can only put it up in a Triangle configuration and the performance is : >what I needed input on. : : >How well will a triangle configured loop work and what if the angles of : >the triangle are not all equal? : : >Any input greatly appreciated! : : >73, : : >de KE4FPS, David : >ke4fps@iglou.com : : I put up 160 and 80 meter loops and they are seldom equal lengths on a : side. Put as much wire as you can, feed it with either coax or ladder : line and use a tuner..it will work out fine. BTW get it as high as : possible at each point. : : I have a 310 foot full wave loop up on St Simons Island and have : worked thousands of DX stations on 80 to 10 including WARC bands. : : Too bad you can't put up a tower but the loop is the next best thing! : : Dave K4JRB : : Hi David, I can vouch for the loop. I just put up a 142 ft triangular loop, probably at an average height of 30 ft. Fed at a corner with coax (70 ft.). Tunes extremely well using the built-in tuner in my Yaesu FT-900/AT on all bands above 40 m. At 40, I find that a transmatch is necessary. I can confirm that the antenna is very quiet and gets reports (especially on 20m) that I would not have thought possible given my 75-100 watts. I recommend it strongly based on my recent experience. Good Luck! 73 de NT3G From amsoft@epix.net Mon Jul 01 12:23:10 1996 From: jafl@msg.ti.com (Jim Flanders) Newsgroups: rec.radio.amateur.antenna Subject: Re: DDRR antenna -reply to comments Date: 28 Jun 1996 14:24:26 GMT Message-ID: <4r0puq$8jt@ganesh.mc.ti.com> References: <4qm5hn$jij@ganesh.mc.ti.com> <4qoktg$4u1@newsbf02.news.aol.com> Tom It may be a useless test, but a two-meter model of the antenna gave the same results with the receive antenna revolving around the vhf ant. Perhaps the reason for the same results is on 40 meters, the test range allowed me to drive the van up a 15 foot birm. The antenna was on top of the van, so add another seven feet. In between the birm and the 70 foot high receive antenna was very dry & deep Texas sand. (We had .6" rain at that spot in 6 months) I believe their was little enough action by the ground environment to give me some indication of the vertical pattern of the horizontally polarized wave. BTW - another alteration was made (actually because of some of your comments). I put the feed point (this is no longer a true DDRR) down at the bumper of the van. I ran the 2 1/2" pipe up the back of the van (7'), and then coiled the rest of the (27') pipe on the top like the DDRR was. I haven't done the A vs. B testing yet. Remember this - my overall purpose is to develop the most efficient 40 meter mobile antenna that will tune the whole band. Jim W0oog/5 in Plano, TX (Plain Ole Texas) Tom's prev. comment: > >By the way, tilting the antenna over real ground does not allow you to >plot the elevation pattern. > >It is a useless test. > >73 Tom From amsoft@epix.net Mon Jul 01 12:23:11 1996 From: Dave Potter Newsgroups: alt.ham-radio.vhf-uhf,alt.ham-radio.am,alt.ham-radio.fm,alt.ham-radio.ssb,rec.radio.amateur.dx,rec.radio.amateur,rec.radio.amateur.antenna,rec.radio.amateur.equipment Subject: Re: Antenna Driving me nuts Date: 28 Jun 1996 15:36:40 GMT Message-ID: <4r0u68$b1i@xenon.brooks.af.mil> References: <4qsk9b$s84@news.inforamp.net> Chrisv@valteck.com (Chris Valliant) wrote: > Here is what I am trying to do: to build a 1/2 wave >diapole for the 28-29 mhz. I splice the coax, solder one end to a length >of wire 8.2 feet and the other braided end to a length of wire the same >size. I suspend both ends using insulated clamps between two tree's, >making sure that the whole antenna is parallel to the ground and it's 8 >feet above the ground. Chris - I'm not an antenna expert, but I'd look at the following: 1) It's my understanding that if you just attach the center conductor and shield to the two halves of the antenna directly, your feed line will become part of the antenna, and it will radiate. Your transmitter may be looking at an antenna a whole lot longer than just the two 8 foot sections. That would explain the high SWR. Better to get a balun which has screw connectors for the two antenna pieces, and a SO-239 connector for your feedline. I think a 1:1 balun would work, but I could be wrong on that. 2) Height may be part of the problem. 8 feet high isn't much. 3) What do you mean "insulated clamps"? I'd get some insulators and suspend the antenna by some rope or wire, tying the suspension wire to one side of the insulator, and the antenna section to the other end of the insulator. That's the way I've seen dipoles hung before. 4) Parallel to the ground isn't as critical as some of these other things, I think. 5) Why 28-29 MHZ? The band's dead. From amsoft@epix.net Mon Jul 01 12:23:12 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Decoupling Feedlines Date: 28 Jun 1996 16:37:10 -0400 Message-ID: <4r1fpm$6bv@newsbf02.news.aol.com> References: <2.2.32.19960628053223.0068ccb0@hevanet.com> In article <2.2.32.19960628053223.0068ccb0@hevanet.com>, ashworth@hevanet.COM (Dennis / Vivian Ashworth) writes: > >My plan is to decouple the feed line and control cable with several Amidon >FB-77-1024 ferrite beads. I suspect I'll need 8-10 beads per "choke" to >provide sufficient reactance for 80M, and probably will need to repeat the >"choke" at intervals of about 25 feet (inside of 1/4 wavelength on highest >freq ... 40M). > >Does this sound like a reasonable approach? > >Dennis, K7FL > > Hi Dennis, I don't know what sufficent reactance is in your application, but 77-1024 sleeves I have tested measured an average of 36.1 ohms -13.37j per sleeve at 3.7 MHz. They are the equivilent of a pure resistance of around 36 ohms in series with a little capacitive reactance at that 3.7 MHz, so they will dissipate all the power applied. I'd forget the ferrites and use two air wound chokes. I suspect by the time enough ferrite sleeves are used the feedline will be too heavy to support. An air choke would cost less and function much bettter in a single band application. 73 Tom From amsoft@epix.net Mon Jul 01 12:23:13 1996 From: w8jitom@aol.com (W8JI Tom) Newsgroups: rec.radio.amateur.antenna Subject: Re: Buried radials: Insulated or bare? Date: 28 Jun 1996 16:41:50 -0400 Message-ID: <4r1g2e$6gq@newsbf02.news.aol.com> References: <4qvlfe$p1s@dfw-ixnews3.ix.netcom.com> In article <4qvlfe$p1s@dfw-ixnews3.ix.netcom.com>, mravitz@ix.netcom.com (Mitchell Ravitz) writes: >I remember reading somewhere that ground radials were more efficient >if they were above the ground. I may be wrong here, it was quite a >while ago. Anyone know? > >Mitch >WA1DTX There have been computer models indicating such Mitch, but no independent confirming measurements. There is some question as to the accuracy of the elevated radial models, since they don't always seem to work the way predicted. For exaple, at a radio station in New Jersey, when six elevated radials were replaced with 100 plus radials on the ground, FS increased just over 5 dB. Here at my location 4 elevated radials were almost 5 dB down from 60 radials on the ground. And with 60 radials it made no difference whether they were elevated or on the ground. The jury is still out, and probably will be for a long while until MORE real world tests are made. 73 Tom From amsoft@epix.net Mon Jul 01 12:23:15 1996 From: Jean-Pierre BÉLISLE Newsgroups: rec.radio.amateur.antenna Subject: Re: 80 meter vertical advice wanted Date: Fri, 28 Jun 1996 22:46:51 -0700 Message-ID: <31D4C34B.1F@sympatico.ca> References: <31CF265F.4B31@jetisi.com> Gene Shablygin wrote: > > Hi! > > I am considering installation of a 80 meter vertical in my > back yard. I do not have space for guys, so the antenna should > be free standing. Until now, I see a few options: Butternut > HF2V (although too short to be good on 80), Force 12, HyGain > 18HTS, and new Mosley (if this thing really exists). If anybody > had a chance to compare those things, and can share his opinion, > it will be highly appreciated. > > Maybe, I will be brave enough to install couple of those to set > up a phased array. Any comments will be also welcome. > > 73 Gene AB5GY / RA3AA Have you considered KLM SSV 80-40-15? - Freestanding vertical; - Lower half standing on three electrically active tripod legs; - Two legs serve as hinge points, raised and lowered by two persons; - Only modest base preparations needed; - The upper half of the SSV is a single telescoping whip section; - The tip reaches more than 60 feet above ground;(tripod = 30') (despite it's height, the design technically satisfies the city bylaw) - Single tunable element to top - Wind survival 100 MPH - Weight: 88 lbs - Power Handling: MAx legal + Cost a bit more ... but impessive quality of the components! Jean-Pierre Belisle Montreal, Quebec From amsoft@epix.net Mon Jul 01 12:23:15 1996 From: n7tcf@primenet.com Newsgroups: rec.radio.amateur.antenna Subject: Coax connectors at UHF Date: 29 Jun 1996 06:03:02 -0700 Message-ID: <4r39i6$53n@nnrp1.news.primenet.com> Reply-To: n7tcf@primenet.com More important than slight impeadance bumps is the overall quality of the con nector. I took my box of assorted jumpers and connectors to work and sweep them with a network analyzer. Some connectors had .2-.3 dB loss at 2m. The worst were some cheap n ickel-plated with a nickel-plated center-pin. Some old silver-plated connectors had the same los s. Look for name-brand, silver-plated connectors. If the cheaper stuff must be u sed, (several still in my system) keep it in the lowest band. The network analyzer I have access t o only goes to 300 MHz, so .2 dB at 300 means much more at 432 MHz. My new standard is gold center pins for N and BNC. For 239/259, well I avoid them because they have no weather sealing and such a pain to install. Jim N7TCF From amsoft@epix.net Mon Jul 01 12:23:17 1996 Newsgroups: rec.radio.amateur.antenna From: kb5iav@popalex1.linknet.net (Jonathan Helis) Subject: Re: Indoor HF antenna Message-ID: <61d7cc$01737.1ff@NEWS> Date: Sat, 29 Jun 1996 07:20:18 GMT References: <31CC5E90.1074@lex.infi.net> "Aaron J. Welch" wrote: >Got a small problem... > I recently moved into a 2 bedroom apartment, and I'm prohibited from putting any type of external >antenna outside (tv, amateur, etc). I've got a Kenwood TS-130S rig, and I rea lly hate to give up my HF >work just because of my living conditions. I'm looking for some kind of indoo r antenna that will generally >cover 80-10m (at least 80-20), and won't cost an arm and a leg. I know there are some indoor antennas on >the commercial market, but most of those that I've seen are either way out of my price range, or they're just >"too good to be true". I can handle just about any type of antenna (wire, coa x, etc). If you have any >suggestions as to what I could do, please e-mail me. Any and all assistance i s greatly appreciated. >-73- de KE4ENO >truant@lex.infi.net >btw- I've already tried stringing up a wire around the tops of my walls, but I've had no success. :) Have you tried an MFJ-1621? That's a 54 inch whip that tunes 40-10 meters. I've had some success with it, working several hundred miles on 40 meter CW at 100 watts or less. They run around $80.00 or so, less if you shop carefully. The AEA Isoloop works 30-10 meters effectively, but is expensive(mine was $320.00 a couple of years ago.) Do you have a balcony? I've had success stringing up a random(whatever size I can put up) square loop on a balcony fed with twinlead and an antenna tuner. A little imagination is all it takes. Good luck! 73, Jon Helis, KB5IAV Baton Rouge, Louisiana, USA kb5iav@linknet.net From amsoft@epix.net Mon Jul 01 12:23:19 1996 From: pacrimgolf@kuentos.guam.net (Jim Kehler) Newsgroups: rec.radio.amateur.antenna Subject: Re: Proper guy wiring for 2 meter vertical Date: Sat, 29 Jun 1996 10:54:34 GMT Message-ID: <4r35gn$6t4@lehi.kuentos.guam.net> References: <31D39DA7.46BC@pacbell.net> Reply-To: pacrimgolf@kuentos.guam.net Bill Faust wrote: >I'm a new Tech (November) and need some help or advice on where to look for i nformation on the proper way(s) >to guy a mast. I want to put up a 2 meter Vertical on a 25' mast but I don't know where to look to find the >information needed about how to guy the mast. The mast must be free standing (i.e. away from the house) as >I'm renting and well... I studied ARRL's "Now Your Talking" to get the Tech lic. but it did not say a word >about guying the mast. Is there a magic formula or better yet a good book I can read that will teach me what I >need to know? I've been told the guy lines should be measured in 1/4 meter l enghts from the base of the mast, >as well as they should be in 1/4 meter lenghts from the mount point on the ma st down to the ground. I've also >been told they should be insulated... What is the real "skinny"? >Thanks much! >Bill Faust KE6ZQH >Working on the code Bill, since your mast will only be 25' high with a vertical antenna, it won't have a lot of wind load. Rather than worrying about using metal guys and cuting them up with insulators, I think your best bet would be to use some heavy nylon line or rope, which is easier to handle and won't interfere with the antenna pattern. I've used parachute cord for guys for lots of different masts, even on with a rotor/beam on it. How you attach the base of the pole to the ground with have a lot to do with how many guys you need, but if the base is in another pipe, or a couple feet into the ground, probably one set of either 3 or 4 guy lines at about 19 or 20 feet should do the job. 73, Jim KH2D From amsoft@epix.net Mon Jul 01 12:23:19 1996 From: efeustel@fricka (Edward Feustel) Newsgroups: rec.radio.amateur.antenna Subject: Re: Answer to: What's a big wheel Date: 29 Jun 1996 11:28:33 GMT Distribution: na Message-ID: <4r3411$619@news.ida.org> References: <4r14mv$t3h@omnifest.uwm.edu> I have a set of stacked big wheels that I got from Cushcraft back in the 60's with instructions. Worked well for me when put on a metal mast about 35 feet tall. Down now for replacement of cables. Anyone know why Cushcraft discontinued them? (use e-mail to reply please) Ed, N5EI -- Edward A. Feustel, Research Staff Member Institute for Defense Analyses Phone: (703)-845-6657 1801 N. Beauregard Street Fax: (703)-845-6848 Alexandria, Va. 22311-1772 Email: efeustel@ida.org From amsoft@epix.net Mon Jul 01 12:23:20 1996 From: "Bram Bottema ( SM0FLY)" Newsgroups: rec.radio.amateur.antenna Subject: Need F53 Fritzel info Date: Sat, 29 Jun 1996 11:53:09 +0100 Message-ID: <31D50B15.1939@medonic.se> Hi and thanks for reading this. Since many years I'm using a FB53 yagi. A few years ago I decided to change the traps due to damage by some haevy weather. It took a long time to get the new parts ( more than 1 1/2 years !!) just to recover that Fritzel changed their design and that the new parts were not compatible with my 'old' FB53 from 1982. A few months ago I finally got the additional parts but there were no dimension drawings in the package. Fritzel never responded to my faxes ( about 8 times I tried ), so: Can anyone help me with the (new) drawing of the FB53 ? If you have this info, please dropp me a line. Of course I'll pay any expenses. Thanks es 73 ! /Bram -- ========================================================== e-mail : bram.bottema @ medonic.se PGP public-key : http://www.pi.se/sm0fly/pgp.asc URL : http://www.pi.se/sm0fly/sm0fly.htm ========================================================== From amsoft@epix.net Mon Jul 01 12:23:21 1996 From: cragjock@aol.com (Cragjock) Newsgroups: rec.radio.amateur.antenna Subject: patch antenna polarization ?? Date: 29 Jun 1996 12:17:44 -0400 Message-ID: <4r3kv8$st3@newsbf02.news.aol.com> Reply-To: cragjock@aol.com (Cragjock) hey all how do i feed a patch antenna to get circular polarization ?? any ideas ?? thanks sc From amsoft@epix.net Mon Jul 01 12:23:22 1996 From: PSS Newsgroups: rec.radio.amateur.antenna Subject: WTB: 2M 6M Vertical antenna Date: 29 Jun 1996 12:51:29 -0700 Message-ID: <4r41g1$nbf@doc.zippo.com> Looking for 2M/6M vertical at a reasonable price. Send into to petsits@surf.galacticis.com TNKS From amsoft@epix.net Mon Jul 01 12:23:23 1996 From: raiar@inlink.com (Gary V. Deutschmann, Sr.) Newsgroups: rec.radio.amateur.antenna Subject: Re: Want Any 6 MTR Vertical Designs, Plans... Date: Sat, 29 Jun 1996 14:20:09 GMT Message-ID: <4r3eg4$n4m@news2.inlink.com> References: <4qpi9f$4nm@news.aros.net> mfp@aros.net (mfp) wrote: >Anyone have any 6 meter OMNI GAIN plan's or Antenna design's.. >we need a new 6 mtr Repeater antenna and our 3 db ringo just aint cuttin' it. . >ANYTHING would help out! >Marc Peterson, Pres >RMRA Rocky Mtn. Radio Association >mfp@aros.net Try a pair of 6-meter mirror image J's, they'll outperform a ringo any day. Cost about 7 bucks each. see http://www.inlink.com/~raiar TTUL Gary From amsoft@epix.net Mon Jul 01 12:23:24 1996 From: pmarkham@sun.lssu.EDU (Peter Markham) Newsgroups: rec.radio.amateur.antenna Subject: Re: HAARP info requested Date: 29 Jun 96 14:46:06 GMT Message-ID: <199606291446.KAA24459@sun.lssu.edu> I follow this HAARP thread, and others, with interest. Valid points have been made concerning psuedo science, sophistry and writing. May the debunkers prevail. I am appalled that quotes and references from the words of legislation? and politicians are used as sources of "objective" information concerning justification and explaination of issues of physics. I tend to view politicians, and their products, as information sources of la st resort for explaining anything with a rational basis. Politicians' ends justif y their reasoning. The objective, nature of physics does not mesh well with the subjective nature of politics. Pete/wa4hei From amsoft@epix.net Mon Jul 01 12:23:25 1996 From: Bill Crocker Newsgroups: rec.radio.amateur.antenna Subject: 2m/70cm Mobile Antenna? Date: Sat, 29 Jun 1996 18:17:32 -0700 Message-ID: <31D5D5AC.650D@rust.net> I want to put a dual-band (2-m, 70-cm) antenna on a Jeep Wrangler. I have to keep low profile to get in and out of my garage. Any suggestions? Do the through'the'glass units work very well? I'll be running up to 50-watts on VHF. Thanks, Bill Crocker From amsoft@epix.net Mon Jul 01 12:23:26 1996 Newsgroups: rec.radio.amateur.antenna From: Erich Muschinske Subject: Re: Answer to: What's a big wheel Message-ID: <31D598F8.60BA@ridgecrest.ca.us> References: <4r134a$1pi@ganesh.mc.ti.com> Date: Sat, 29 Jun 1996 20:58:32 GMT Jim Flanders wrote: > > I received some e-mail asking what is a big wheel. > > First some history. Back about 1947 when I was in grammer school I > converted my DAD's 2 1/2 meter gear to 2 meters. There was lots of > activity on the Connecticut shoreline (and the ARRL) on two. All the > polarization was horizontal. I needed an all-direction antenna for > the evening rag chews. I found in the Navy ETC training manual a > design using 3 dipoles in a ring and built it. When I showed it to > my VHF mentor (Dr. Bob Mellon W1IJD) he modified it to what is now > the Big Wheel. It sorta looks like a three leaf clover, and uses 3 > one wavelength loops. (80" on two). W1IJD took the idea to Les > Cushman who marketed it. The best how-to-build I now of is in the > RSGB (3rd edition) VHF-UHF Manual. > Jim W0OOG/5 Jim, Could you provide any details of how the feed works? Unfortunately my version of the RSGB VHF-UHF (4th ed.) Manual doesn't have the Big Wheel in it. 73, Erich KA6AMD DM15bp erich@ridgecrest.ca.us From amsoft@epix.net Mon Jul 01 12:23:27 1996 From: aa5mt@gate.kc5aug.ampr.ORG Newsgroups: rec.radio.amateur.antenna Subject: DDRR comments Date: 30 Jun 96 02:45:59 GMT Message-ID: <128041@gate.kc5aug.ampr.org> Reply-To: aa5mt@gate.kc5aug.ampr.org DDRR Antenna - Personal experience I've read about the DDRR antenna since the 70's in 73 magazine and others. It's always had my interest, since it's small, and I've lived in mostly small locations. I have not owned or made a DDRR, but in a sense I did make one. I had one of the MFJ-1786 loop antennas on loan when I made a business trip to Dallas. I had a new TS-450SAT and wanted to take it with me mobile. Rather than buy a mobile antenna, I made do with the loop antenna. This was in 1993 when the bands were very bad. The MFJ loop covers 10-30 great either horizontal or vertical oriented. In deciding to use the loop, I remembered reading the article on the DDRR, and figured that the loop would be a fairly close approximation to the DDRR. The article had a 'downspout' from the main loop to the counterpoise, which was the only visible difference, besides the tuning capacitor, that I could see. The article said that it was mounted about a foot off the counterpoise. I used this figure for my initial mounting height. I didn't know what I had around for a mount for the roof of the car(Taurus wagon). I was in the dollar store and spotted dishracks for a dollar. I got two and turned the second one upside down over the first one, making an insulated box about 1 foot high. I glued them together with rtv rubberseal, and taped the edges for extra security. Being plastic, the racks weren't strong enough for the loop, since pressure distribution was not even. A piece of plywood on top and bottom of the cage fixed that. The wagon has tie downs on the back of the roof and over the front seats. I secured the loop between them with bungy cords in a horizontal orientation. It looked strange, but no worse than any other hf mobile antenna, and a lot smaller at that. Several people asked me what I had on the roof when I stopped for gas. One guy thought I was in a band, with my guitar up there. He didn't see the loop, only the motor cover. I had just a little shifting the first hundred miles, but ok every couple of hundred after that. Performance was expected to be minimal, but I did expect some, since the antenna worked so well at home. I made a few contacts in the driveway; all gave me ok signal reports. I don't use S-meter readings anymore. You can give false readings, wrong readings, etc, depending on the radio brand and operator temperament(octane). What I got really surprised me. I stayed busy almost the whole trip, making contacts on 17 and 20 meters. I don't use cw much that year, so didn't try 30, but heard it fine. I worked probably 30 states on that trip. 10 and 15 never were heard at all, which was normal that year. Outside of Dallas about 30 miles, I checked into the Florida morning net on 20 meters, about 8 am or so. I talked with some of the guys who gave me weak but readable signal reports. We talked for about 20 minutes or so. After I signed off, I went to check the antenna tuning. My radio was still in the minimum power setting! I turned the power up to 100 watts and checked back in. Now they said I sounded like a big dog! Just goes to show that a small antenna running qrp, mobile can be made to operate. Don't know if you'd call this a DDRR, but if it looks like a duck, and you can make duck soup out of it, maybe it's the real McCoy. Then again, maybe it just tastes like chicken. 73B4U81 Tom Stone AA5MT@gate.kc5aug.ampr.org From amsoft@epix.net Mon Jul 01 12:23:28 1996 From: popcorn@atcon.com (Chris Campbell) Newsgroups: rec.radio.amateur.dx,rec.radio.amateur.antenna Subject: FM Suggestions Date: Sun, 30 Jun 1996 04:54:18 GMT Message-ID: <31d5bcf9.8077365@news.atcon.com> I know the basics about FM reception as in hight makes a lot of difference. I was looking around in my attic and I found a huge antenna just lying around, it's about 3 meters long and 2 meters wide. I put it up in the rafters and bought a wire to hook it to my stereo downstairs. The antenna looks like this: ---------------|--------------- | | ---------------|--------------- | | ---------------|--------------- | ___________|___________ ---------------|--------------- | ---------------|--------------- ---------------|--------------- I find I am now able to pick up much more stations, I plan to start recording them soon. I know this antenna was bought about 20-25 years ago to pick up television signal because then there was no cable. I'm just wondering if this design is outdated or there is anything else I might want to buy in it's place for the best reception. Should I get a signal amplifier? Thanks for the help From amsoft@epix.net Mon Jul 01 12:23:29 1996 Newsgroups: rec.radio.amateur.antenna From: anarchyu@olywa.net (ANaRcHyU) Subject: Help on building 2 meter mobil antenna Message-ID: <31d609b8.1737577@news.olywa.net> Date: Sun, 30 Jun 1996 05:07:31 GMT Howdy.. I want to build my own 2 meter antenna for my handheld radio which i will be using in my truck.. I am on a extremly tight budget ( i mean i have like 20 bucks i can spend) i have a bunch of connectors and such that i have from a antenna i made that plugs right onto my radio and that works great, but doesnt work great when i am driving. I have a large rectangular magnet (which i can cut to size) for making it magnet mountible. If anyone has an IDEA or drawing or something they can send me that may help, PLEASE e-mail me at KC7QZR@olywa.net and tell me!! I also have a supply (60 feet or so) of 12 gauge copper house wire (new never used) if that would work for part of the antenna. Thanx for any help you can give!! Brad _\\|//_ (` o-o ') -------------------------------ooO-(_)-Ooo-------------------------------- KC7QZR {this page under construction} KC7QZR@olywa.net .oooO Oooo. http://www.geocities.com www.olywa.net/anarchyu ( ) ( ) /SiliconValley/Park/1594 ------------------------------\ (-------) /------------------------------- \_) (_/ Proud to say I am a Member of the Capitol Peek Repeater Group! 145.470 - Tumwater Wa. From amsoft@epix.net Mon Jul 01 12:23:30 1996 From: bduxbury@zetnet.co.uk (Sir Barry Duxbury) Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment Subject: Re: Antenna Driving me nuts Date: Sun, 30 Jun 1996 07:07:58 +0100 Message-ID: <4r56d6$7ah@roch.zetnet.co.uk> References: <4qsk9b$s84@news.inforamp.net> In message charles1@netcom.com (charles copeland) writes: > In article <4qsk9b$s84@news.inforamp.net>, > Chris Valliant wrote: > > > > > > I have been trying for the last two weeks to build a half wave > >diapole antenna. Just a general observation. This thread appears to tell us a lot about the US licensing standards. In 40+ years I have never seen anyone having a problem with a simple dipole or the underlying basic principles. What has really made me comment is the pattern of very elementary questions which appear on the net frm licencesed hams. I accept thar Chris may not be a ham and certainly this comment is not critical of him. 73 Barry -- Barry Duxbury bduxbury@zetnet.co.uk 100031.2223@compuserve G4GAH Oxford UK