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Re: [TowerTalk] How to best determine the need for a balun

To: <>
Subject: Re: [TowerTalk] How to best determine the need for a balun
From: "Tom Rauch" <>
Reply-to: Tom Rauch <>
Date: Sat, 16 Oct 2004 07:33:49 -0400
List-post: <>
>     a) I need a 1:1 balun as the feedline is part of the
> (Doesn't make sense as the sweet spot should've gone down
toward 1800 as
> the radiator is lengthened?)

With 27 radials, the ground should be pretty good. It would
be unlikely you need a current balun or choke at the
feedpoint. Your high feedpoint resistance puzzles me. Sounds
like a metering problem, or the tree or something having an
effect. What meter are you using? BC RF into the meter?

>     b) I've created a wiry outside dummy load? (the few
tests done
> comparing a 1/4 sloper and a dipole at 70' with the 27
radial beauty
> with stations on the right coast indicate anywhere from a
6 to 18 dB
> improvement over the dipole and sloper so maybe it's just
slightly less
> of a dummy load than the other two?)

My verticals typically average about 10dB over low dipoles
at modest distances (200-500 miles) and as much as 20dB at
longer distances at times. My low dipole wins within 100
miles. So it sounds like you are in the ballpark.

>     c) I should just shut up and try the thing out and
first time I
> can't work a particular station, blame it on the lack of a
balun and
> then install one?

Blame it on the tree. You should not have much coax shield
current with the number of radials you have. If you only had
four or five radials, it would be another story. Then you
would definately have a scapegoat.

73 Tom


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