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1994-11-13
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Date: Thu, 26 May 94 04:30:10 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 #159
To: Ham-Ant
Ham-Ant Digest Thu, 26 May 94 Volume 94 : Issue 159
Today's Topics:
"J pole" like antenna using coax instead of twinlead?
Dipole help
Dipole in attic UPDATE?
Looking for radiation pattern of full-wave vertical.
Quoting Diarrhoea
Using Mininec for UHF/VHF antennas?
Using Mininec for VHF/UHF antennas
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: Thu, 26 May 1994 01:14:30 GMT
From: ihnp4.ucsd.edu!library.ucla.edu!csulb.edu!csus.edu!netcom.com!wa2ise@network.ucsd.edu
Subject: "J pole" like antenna using coax instead of twinlead?
To: ham-ant@ucsd.edu
The twinlead J pole antenna seen many times on these groups works well.
Turns out I have lots of coax scraps, but not much twinlead. (you
mean, actually go out and BUY something! :-( ). I have 50 ohm, 75 ohm,
and some 93 ohm coax scraps (RG's 58, 59, 62). Is there a design similar
to the Jpole I can build with these scraps of coax? for VHF? 2M?
------------------------------
Date: Thu, 26 May 1994 06:08:09 GMT
From: ihnp4.ucsd.edu!library.ucla.edu!csulb.edu!csus.edu!netcom.com!wa2ise@network.ucsd.edu
Subject: Dipole help
To: ham-ant@ucsd.edu
In article <2s010i$rh1@chnews.intel.com> cmoore@ilx018.intel.com (Cecil A. Moore -FT-~) writes:
>
>Quoting from the ARRL Antenna Book, "Greatly improved choke balun
>performance can be realized by placing several ferrite beads... around
>the coaxial feed line." For 10m, a dozen no. 73 beads (Amidon no. FB-
>73-2401) close to the antenna feed point should work.
>
One nice thing about the ferrite beads around the coax at the feed point,
or using several turns of coax to make a choke at the feedpoint, is that
the xransmitter power is not directly applied to the ferrite or choke.
So the ferrite won't saturate as much as it might if you used an actual
transformer-like balum. The choke coil above acts in a "common mode"
like mannor, both inner and shield conductors of the feedline coax
go thru the choke together, and as such, don't "notice" the choke's
presence. Any RF currents on the *outside* of the outside shield
conductor of the coax will "notice" the choke, and attenuate them.
------------------------------
Date: 26 May 1994 02:49:18 GMT
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!noc.near.net!news.delphi.com!domonkos@network.ucsd.edu
Subject: Dipole in attic UPDATE?
To: ham-ant@ucsd.edu
>I installed an inverted V dipole in my attic (not really an attic more like
>a crawl space) for my CB. Seems to work fine except for one thing. There
is
>a lot of interference. Sounds like a dishwasher on the line. Anyone
>have any ideas on what may be causing it and what I can do to get rid of
it.
>
>---
>Thank you,
>Arik Klingensmith arik.klingensmith@ebay.sun.com
>
>
A good noise blanker is just about all that will help. Good luck (BTW, the
noise isn't as bad if you switch to SSB).
Andy
------------------------------
Date: Wed, 25 May 1994 21:45:10 GMT
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!wupost!crcnis1.unl.edu!newsfeed.ksu.ksu.edu!moe.ksu.ksu.edu!osuunx.ucc.okstate.edu!olesun!gcouger@network.ucsd.edu
Subject: Looking for radiation pattern of full-wave vertical.
To: ham-ant@ucsd.edu
In article <1994May25.164547.12310@vfl.paramax.com>,
Pete Rossi <rossi@VFL.Paramax.COM> wrote:
>I am looking for a plot of the vertical radiation pattern of a full-wave
>ground mounted vertical.
>
>Last year for FD I used a 33' half-wave vertical on 20 meters. It worked
>great. This year I will be operating both 20 and 40 meters and I plan to use
>a 66' half-wave vertical for 40 and was wondering what kind of performance I
>might expect with it on 20 meters as a full-wave vertical?
>
Elnec shows a radiation angle of 34 degrees for a full wave over real
ground. I don't really know what this will do on 20. It's a lot higher
than I have ever used for any length of time.
It is in one well defined lobe.
Good luck
Gordon AB5DG
>If I remember correctly, a full-wave vertical has several high-angle lobes
>but I wonder if for FD type operation it might still do pretty good.
>
>I would like to be able to go with one antenna for both bands and NOT use
>a quarter-wave on 40. I don't want to have to provide the extra grounding
>that a quarter-wave needs to work right.
>
>I am expecting the half-wave vertical should work pretty good on 40. I just
>wonder how much the 20 meter performance will suffer.
>
>=================================================================
>Pete Rossi - WA3NNA rossi@vfl.paramax.COM
>
>Unisys Corporation - Government Systems Group
>Valley Forge Engineering Center - Paoli, Pennsylvania
>=================================================================
------------------------------
Date: Thu, 26 May 94 05:17:33 GMT
From: ihnp4.ucsd.edu!agate!library.ucla.edu!csulb.edu!csus.edu!netcom.com!netcomsv!skyld!jangus@network.ucsd.edu
Subject: Quoting Diarrhoea
To: ham-ant@ucsd.edu
In article <1994May25.165809.18939@rsd.dl.nec.com> dave@rsd.dl.nec.com writes:
> >>What's "diarrhoea"?
>
> Maybe it's a typo and he meant "diary of Ean".
>
> dave
Diarrhoea is the accepted alternate (British) spelling of diarrea.
Amateur: WA6FWI@WA6FWI.#SOCA.CA.USA.NOAM | "You have a flair for adding
Internet: jangus@skyld.grendel.com | a fanciful dimension to any
US Mail: PO Box 4425 Carson, CA 90749 | story."
Phone: 1 (310) 324-6080 | Peking Noodle Co.
Hate "Green Card Lottery"? Want to help curb ignorant crossposting on Usenet?
E-mail ckeroack@hamp.hampshire.edu for more information, or read news.groups.
------------------------------
Date: 25 May 1994 20:38:25 -0700
From: nntp.crl.com!crl.crl.com!not-for-mail@decwrl.dec.com
Subject: Using Mininec for UHF/VHF antennas?
To: ham-ant@ucsd.edu
I was wondering if anyone had any information on how well Mininec works
with UHF/VHF antennas? I would like to use it to design a 2 meter
antenna. Works good for HF but was wondering how well it would work on
the higher bands. Thanks for any help here! 73!
Jeff Jones
AB6MB
------------------------------
Date: 25 May 1994 20:31:08 -0700
From: nntp.crl.com!crl.crl.com!not-for-mail@decwrl.dec.com
Subject: Using Mininec for VHF/UHF antennas
To: ham-ant@ucsd.edu
------------------------------
End of Ham-Ant Digest V94 #159
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