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1994-11-13
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Date: Fri, 22 Jul 94 04:30:17 PDT
From: Ham-Ant Mailing List and Newsgroup <ham-ant@ucsd.edu>
Errors-To: Ham-Ant-Errors@UCSD.Edu
Reply-To: Ham-Ant@UCSD.Edu
Precedence: Bulk
Subject: Ham-Ant Digest V94 #233
To: Ham-Ant
Ham-Ant Digest Fri, 22 Jul 94 Volume 94 : Issue 233
Today's Topics:
AM Stations....
Antenna forsale
Antenna Patterns??
Attic Dipole Help
DDRR Patterns and Performance
Feedline next to 220V run??
Mag mount help
need info on Ham radios
PSI newsfeeds - Was: rec.radio.amatuer.antenna still alive?
ROHN tower info, please (3 msgs)
RV HF Loop
Trees as antennas, Effects of trees
Send Replies or notes for publication to: <Ham-Ant@UCSD.Edu>
Send subscription requests to: <Ham-Ant-REQUEST@UCSD.Edu>
Problems you can't solve otherwise to brian@ucsd.edu.
Archives of past issues of the Ham-Ant Digest are available
(by FTP only) from UCSD.Edu in directory "mailarchives/ham-ant".
We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party. Your mileage may vary. So there.
----------------------------------------------------------------------
Date: 21 Jul 1994 12:04:10 -0400
From: newstf01.cr1.aol.com!search01.news.aol.com!not-for-mail@uunet.uu.net
Subject: AM Stations....
To: ham-ant@ucsd.edu
In article <2qm0uu$q2g@mother.usf.edu>, shadrick@luna.ec.usf.edu. (Scott
Shadrick (PSY)) writes:
Greetings..
1st answer, yes. You could probably hear stations as far away as Hawaii
and the Far East with proper conditions.
2nd:
WWOW is licensed to Contemporary Media, Conneaut, Ohio. My 1994
Boradcasters Yearbook lists them on 1360Khz at 500 watts, daytime only.
Cheers,
KG7FU @ aol.com
------------------------------
Date: 21 Jul 1994 17:32:21 GMT
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!agate!etch-eshop.Berkeley.EDU!ron@network.ucsd.edu
Subject: Antenna forsale
To: ham-ant@ucsd.edu
Antenna's West TNT no tune on 40 20 10m. Other bands with a tuner.
87ft long off center fed windom.
I can't easily get it into a good position where I live, so I'll
hopefully change to a vertical.
Sells new for $80.00 plus shipping, aprox 6months old.
$60.00 including shipping.
Ron Viegelahn, KE6GLZ
ron@etcheshop.Berkeley.EDU
------------------------------
Date: 21 Jul 1994 06:10:21 GMT
From: ihnp4.ucsd.edu!swrinde!gatech!newsxfer.itd.umich.edu!zip.eecs.umich.edu!yeshua.marcam.com!insosf1.infonet.net!usenet@network.ucsd.edu
Subject: Antenna Patterns??
To: ham-ant@ucsd.edu
Is there any useful antenna pattern programs for the Mac?
DARKON@ins.infonet.net
------------------------------
Date: Wed, 20 Jul 1994 19:26:41 GMT
From: boulder!news.coop.net!news.den.mmc.com!news2!pogo.den.mmc.com!boutell@uunet.uu.net
Subject: Attic Dipole Help
To: ham-ant@ucsd.edu
Hello all.
I'm planning on mounting a Shory All-Bander dipole into my attic this
weekend. The total length of the antenna is about 70 feet. It of course
will be used with a tuner. The problem is that I don't have a 70 foot
continuous length in the attic. The house is 40 feet long and if I
install the antenna in an inverted-vee configuration I can probably get
about 50 feet end to end. Another problem is that the long run in the
attic runs east-west(better north-south coverage) and I would like the
opposite or even a bit of omnidirectional.
One passage I read talked about bending the ends 90 deg in the
horizontal plane both in the same direction like:
| |
| | looking down
----------
||
||
|| feed line
||
Or I thought about doing it in the vertical plane and bend the ends up:
| /\ |
| /||\ |
| / || \ | looking sideways
|/ || \|
||
||
|| feedline
Or ....
I would appreciate any suggestions for best performance, especially east
and west without having a long north-south path to run the dipole.
I am hoping to get the antenna up this weekend.
Thanks in advance.
73, Russ WD0FTF
------------------------------
Date: Wed, 20 Jul 1994 21:27:06 GMT
From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!newsserver.jvnc.net!yale.edu!noc.near.net!ns.draper.com!news.draper.com!jwy1294a.draper.com!jyoungberg@network.ucsd.edu
Subject: DDRR Patterns and Performance
To: ham-ant@ucsd.edu
There was interest in years past (QST and/or 73 articles may even have been
more than a decade ago) in an antenna called a "directional discontinuity ring
radiator." Overly simplified, a DDRR is a quarter-wave vertical, bent into a
circle and then bent over so that the plane of the antenna is parallel to the
ground. The radiation pattern is that of a vertical.
Question: what would be the effect on pattern and performance if the DDRR
element were concentric with a (smaller diameter) conducting cylinder? Can
the available antenna modelling programs handle configurations like
this?
Skip, K1NKR
------------------------------
Date: 21 Jul 94 13:14:12 CDT
From: equalizer!timbuk.cray.com!walter.cray.com!bexar.cray.com!user@network.ucsd.edu
Subject: Feedline next to 220V run??
To: ham-ant@ucsd.edu
I'd like to run some RG8 coax from a 2 meter jpole in my attic ..antenna
restrictions :-( .. to my toyroom...the garage. My other hobby
(woodworking) is requiring a 220V line coming from the attic to the same
'toyroom' for my tablesaw. Its a 2 story house, so I need to feed both
lines through a bedroom closet that is located above the garage. Can I
run both feeds thru the same conduit??
Note...the radio & saw would never be used at the same time, no current
thru the 220V run while I'm operating. I've never been able to chew gum &
pat my head let alone ragchew and make sawdust concurrently ;-)
Thanks for your advice!
- Tom Baltz KC5HEG
trb@cray.com
------------------------------
Date: 20 Jul 1994 14:19:16 -0700
From: ihnp4.ucsd.edu!usc!nic-nac.CSU.net!ctp.org!not-for-mail@network.ucsd.edu
Subject: Mag mount help
To: ham-ant@ucsd.edu
I have had a Comet b-20 for a few years. Last weekend the mag base mg-sr
developed an open in the center copper of the coax. My attempting to fix
the base has pretty much destroyed it. I am looking for suggestions on a
new mag mount for my B-20. I believe it is a UHF (PL209?) base. Comet
says that everything they have is solid core coax. I think I will have
better luck with a braided core (more flexible) although I don't know if
there will be higher losses with braided.
Thanks
Steve
sadams@ctp.org
------------------------------
Date: 20 Jul 1994 23:06:24 GMT
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!spool.mu.edu!torn!thunder!bb1051-ct3.lakeheadu.ca!dgfowlie@network.ucsd.edu
Subject: need info on Ham radios
To: ham-ant@ucsd.edu
I might want to get into ham radioing in a little while. If this is the
proper newsgroup, would someone please e-mail me the FAQ? If not, just let
me know where else to look.
Thanks muchly.
daryl
------------------------------
Date: 20 Jul 94 13:11:11 EDT
From: psinntp!main03!landisj@uunet.uu.net
Subject: PSI newsfeeds - Was: rec.radio.amatuer.antenna still alive?
To: ham-ant@ucsd.edu
In article <1994Jul15.120359.112@drager.com>, I wrote:
> I've not seen anything in the rec.radio.amateur.antenna group lately. Has it
> been renamed, or do I need to look into a feed problem?
OK - Thanks for the replies. My feed, PSI, informed me that they "upgraded"
their server s/w and some newsgroups got dropped. OOOPS. It's been reinstated.
If you use PSI, you may want to check your feed.
Oh, and yes, the spelling was ok except in my subject line :)
Joe - AA3GN
--
Joe Landis - System & Network Mgr. - North American Drager Co. Telford, PA
landisj@drager.com | uupsi5!main03!landisj | AA3GN@WB3JOE.#EPA.PA.USA
Opinions are mine only, and do not reflect those of my employer.
...Munging Until No Good...
------------------------------
Date: Wed, 20 Jul 1994 22:31:54 GMT
From: ihnp4.ucsd.edu!usc!nic-nac.CSU.net!charnel.ecst.csuchico.edu!csusac!csus.edu!netcom.com!slay@network.ucsd.edu
Subject: ROHN tower info, please
To: ham-ant@ucsd.edu
I am looking for any or all of the following general and specific
information:
1) Street address, telephone, fax, and/or email for ROHN Towers.
2) Specific info on the HD 3-5-54G tower.
Is it a crank-up, fold-over, guyed or freestanding tower?
Is a bracket mount to the house required?
I presume it is 54ft, but do not know for sure.
3) Any idea if Rohn still makes this beast?
4) Is it likely that Rohn makes an updated version which may use the
same concrete mounting?
5) Is it "unusual" that the triangle formation of the mounting
bracket/bolts for Rohn towers are NOT equilateral triangles?
The concrete base I am looking at has a base width of the tower
appearing to be appox 21" althought the distance to the apex
of the triangle base seems to be approx 24" or so. So, perhaps
it was a fold-over mounting bracket? hmmmm
My reason for asking is that I am about to purchase a home built by
a Ham (now Silent Key), and if possible, I'd like to obtain the same
sort of tower .... or at least one that can use the same concrete
base.
Thanks and 73
Sandy WA6BXH
slay@netcom.com WA6BXH@N0ARY.#NOCAL.CA.USA
------------------------------
Date: 21 Jul 94 17:20:46 GMT
From: news.delphi.com!BIX.com!hamilton@uunet.uu.net
Subject: ROHN tower info, please
To: ham-ant@ucsd.edu
slay@netcom.com (Sandy Lynch) writes:
>I am looking for any or all of the following general and specific
>information:
>1) Street address, telephone, fax, and/or email for ROHN Towers.
Rohn
P.O. Box 2000
Peoria, IL 61656
Ph 309-697-4400
FAX 309-697-5612
>2) Specific info on the HD 3-5-54G tower.
> Is it a crank-up, fold-over, guyed or freestanding tower?
> Is a bracket mount to the house required?
> I presume it is 54ft, but do not know for sure.
>3) Any idea if Rohn still makes this beast?
Rohn towers are all basically guyed designs with an optional
fold-over. You buy as many sections as you want for the height
you're looking for. You control the wind load capability by
the choice of how heavy-duty you go in the sections you use.
The 54G does not mean it's a 54' tower, it just means that they
used Number 54G tower sections. I don't see those in the current
catalog, but for comparison, 55G is the current top-of-the-line
consumer tower.
I'd direct your other questions directly to Rohn.
Regards,
Doug Hamilton KD1UJ hamilton@bix.com Ph 508-358-5715
Hamilton Laboratories, 13 Old Farm Road, Wayland, MA 01778-3117, USA
------------------------------
Date: 21 Jul 94 15:05:36 GMT
From: ihnp4.ucsd.edu!swrinde!howland.reston.ans.net!vixen.cso.uiuc.edu!aries!hawley@network.ucsd.edu
Subject: ROHN tower info, please
To: ham-ant@ucsd.edu
slay@netcom.com (Sandy Lynch) writes:
>I am looking for any or all of the following general and specific
>information:
>1) Street address, telephone, fax, and/or email for ROHN Towers.
Rohn, P.O. Box 2000, Peoria, Illinois 61656
Chuck Hawley, KE9UW in Urbana, Illinois
hawley@aries.scs.uiuc.edu
School of Chemical Sciences, Electronic Services
University of Illinois, Urbana-Champaign
------------------------------
Date: Thu, 21 Jul 1994 10:41:21
From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!europa.eng.gtefsd.com!newsxfer.itd.umich.edu!jobone!fiesta.srl.ford.com!eccdb1.pms.ford.com!eve542.eve.ford.com!spierson@network.ucsd.edu
Subject: RV HF Loop
To: ham-ant@ucsd.edu
How would a horizontal HF loop work on the roof of my motor home ? It has a
steel cage and a fiberglass outer shell. The roof area is about 22'x8' and is
11' high. Although I have a rear hitch, a vertical would be parallal with and
only 4' away from the steel cage at the rear. Also has anyone had any luck
using Elnec to model Hf antenna's on motor homes ?
------------------------------
Date: 21 Jul 1994 19:47:03 GMT
From: news.tek.com!tekgp4.cse.tek.com!royle@uunet.uu.net
Subject: Trees as antennas, Effects of trees
To: ham-ant@ucsd.edu
Years ago, I had two identical 40m verticals in my back yard. I wanted
to measure their performance as a phased array, so arranged to have a
friend (Wes Hayward, W7ZOI) make some signal measurements at his house,
about a mile away. To begin, I excited each element in turn, with the
other disconnected at the base. (With a quarter-wavelength element, this
effectively removes it from the system.) Wes measured *10 dB* difference
between them! This was a good measurement with a step attenuator, not some
guess from an S-meter. I verified that both elements had the same feedpoint
impedance and were otherwise identical. The only difference was that between
the weak element and Wes' house was a small stand of fir trees. The trees
were roughly a quarter wavelength high and were about 30-50' from the
antenna. I arranged to be able to switch between the elements from the shack
and verified a very substantial attenuation of signals from the direction of
the trees, in the one element. (This turned out to be W6, so the attenuation
was welcome!) Otherwise, they responded equally. Later, I moved the weak
element so the path to Wes' house just skirted the edge of the trees. The
attenuation dropped to 4 dB.
I haven't seen any good studies or measurements of this effect, and haven't
had time to repeat the experiments now that the trees have grown. I don't
know:
- How important the tree height is
- Whether the effect changes with season
- How frequency-dependent the effect is
- What difference there is between types of trees
I *do* know that the effect is real, and definitely can be major. I'd like
to encourage anyone who's interested to do some experiments and share the
results. Just *please* don't give results in "S-units". (My rig's S-units
are 1.4-2.3 dB each depending on where you are on the scale. What are
yours?) A step attenuator, another local station, antennas, trees, and
time are all that are required. Here's your chance to make a real pioneering
contribution to amateur radio. Any takers?
73,
Roy Lewallen, W7EL
roy.lewallen@tek.com
------------------------------
End of Ham-Ant Digest V94 #233
******************************