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940164.txt
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1994-11-13
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Date: Tue, 31 May 94 04:30:12 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 #164
To: Ham-Ant
Ham-Ant Digest Tue, 31 May 94 Volume 94 : Issue 164
Today's Topics:
2 meter thru-glass
Dipole help
Dipole in attic? (2 msgs)
FCC licensing delays
HamSticks....
Maltese quad
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: Mon, 30 May 1994 23:05:57 GMT
From: nwnexus!jhgrud!eskimo!wrt@uunet.uu.net
Subject: 2 meter thru-glass
To: ham-ant@ucsd.edu
In article <CqFIJv.6C6@ra.nrl.navy.mil>,
David Drumheller <drumhell@claudette.nrl.navy.mil> wrote:
> Look here folks. A lot of technical folklore gets passed around the
>amateur community, and some of it is incorrect. But of all the
subjects
>that suffer from the propagation of inaccurate technical folklore, the
>subject of antennas suffers the most.
>
> I have ask for, and have received advice about antenna
installations.
>Some of it good, some of it bad. Many opinion are in conflict:
>
> ...you need a ground plane... no, you don't need one... my
>through-the-glass antenna works great... mine sucked, so I returned
it...
>you must use a balun... why? ... well, just because... RF current
occurs
>on the feedline ... well then why is the coax on top of the ground
plane
>(car roof)?... gee, I don't know, good question...
>
> Now I have to admit that even I have contributed to this problem.
>
> So now I ask the academics out there to respond, not some elec-tech.
>
> Question: Has *anyone* done a comprehensive scientific study of the
>performance of through-the-glass antennas, or any other mobile antenna
>installations. This includes input impedance, radiation patterns, etc.
>I'm looking for an IEEE paper showing how Halen's integral equation is
>solved, and not some QST article with a couple of mismarked graphs
showing
>a radiation pattern measured using a field strength meter from Radio
Shack
>and a tape measure.
>
> Antenna theory is not my specialty, but it would be refreshing to
read
>something written by someone with scientific authority, and not by
someone
>who `know antennas,' but still uses the `left hand rule' to derive the
>magnetic field due to electron current flow.
>
>-Dave
>--
>David Drumheller, KA3QBQ phone: (202) 767-3524
>Acoustics Division, Code 7140 fax: (202) 404-7732
>Naval Research Laboratory
>Washington, DC 20375-5350 e-mail: drumhell@claudette.nrl.navy.mil
Well, we have wine snobs and food snobs, why not antenna snobs?
All the IEEE papers in the world aren't worth a plugged nickel until
some "elec-tech" goes out with FS meter and tape measure in hand and
verifies them. Then and only then will folks believe.
Lighten up, Dave. You need both.
73 de W7LZP
------------------------------
Date: Tue, 31 May 94 02:05:03 -0500
From: news.delphi.com!usenet@uunet.uu.net
Subject: Dipole help
To: ham-ant@ucsd.edu
the human ear, on a steady tone, can detect a 2dB difference.....for many,
a 1dB difference can be discerned.
------------------------------
Date: Mon, 30 May 94 07:56:18 CST
From: ihnp4.ucsd.edu!usc!cs.utexas.edu!howland.reston.ans.net!wupost!slacc.com!doogie@network.ucsd.edu
Subject: Dipole in attic?
To: ham-ant@ucsd.edu
IA>Will 1/2 wave dipole made for a CB work in an attic?
IA>---
IA>Thank you,
IA>Arik Klingensmith arik.klingensmith@ebay.sun.com
It'll work but you won't like it because:
1) Most CBers are vertically polarized - 10 to 25 dB of attenuation.
2) Attic antennas don't radiate as well as outdoor antennas.
(est. 3 to 12 dB of attenuation)
3) Attic antennas produce more TVI, RFI ect - coupling into house
wiring, close proximity to household receiving devices.
4) It's hard to get a good SWR match - an effect of having an object
in close proximity to your antenna.
SLACC STACK BBS - St. Louis, Missouri
The bulletin board service of the St. Louis Area Computer Club
+1 314.367.1903
------------------------------
Date: 31 May 1994 02:39:22 GMT
From: news.delphi.com!domonkos@uunet.uu.net
Subject: Dipole in attic?
To: ham-ant@ucsd.edu
Rather than listening to heresay about 'what someone else said' about attic
antennas, try it yourself and see. When folks start throwing dB loss figures
at you, ask them what they based the figures on. Being in the comm field and
having installed and tested antenna systems w/REAL test equipment I can
guarantee you wood has a minimal attenuating effect on HF frequencies, even
with all the nail and small metal plates up there. Good luck.
Andy
------------------------------
Date: Mon, 30 May 94 07:56:17 CST
From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!wupost!slacc.com!doogie@network.ucsd.edu
Subject: FCC licensing delays
To: ham-ant@ucsd.edu
Patience Daryl, the wait will be worth it.
SLACC STACK BBS - St. Louis, Missouri
The bulletin board service of the St. Louis Area Computer Club
+1 314.367.1903
------------------------------
Date: Tue, 31 May 94 01:49:49 -0500
From: news.delphi.com!usenet@uunet.uu.net
Subject: HamSticks....
To: ham-ant@ucsd.edu
Stick with Lakeview.....better.
------------------------------
Date: 30 May 1994 15:18:38 GMT
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!pipex!sunic!ugle.unit.no!lise.unit.no!kenneth@network.ucsd.edu
Subject: Maltese quad
To: ham-ant@ucsd.edu
Does anyone have a detailed description of this antenna which I'd like to set
up for 20/17/15 meter ??
I understand it's smaller, but still offer me a reasonable performance, and since
I have limited space I'm thinking of building this antenna.
How is this quad compared to the 'real' quad ???
If anyone have experienced this antenna , pse let me know.
Thanks in advance,
Kenneth LA7GIA.
------------------------------
End of Ham-Ant Digest V94 #164
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