No personal experience, but the guy I got a used Colatchco 4-square phasing
switch from said his 40M 4-square stopped working when he installed 100' of
guyed Rohn 45 in the middle of the array (TH-7 and shorty forty on top of
the tower.) I assume this meant that the array was no longer directional. It
was a typical ground mounted 4-square with either 64 or 128 radials per
element and worked very well before the tower went in.
K4SQR, owner of Comtek advised me to put at least a 1/2 wavelength between
my 40M 4-square elements and any large vertical metal objects that might
detune them, like a tower. Obviously, the center of the square is less than
1/4 wavelength from each element, so it would seem that one could not put a
big tower there. However, at the same time we discussed various designs for
tower-supported verical wire 4-square arrays for 80M and 160M. There
certainly are a number of people out there with such configurations, and
they work. Why, I don't know. Can anyone explain the discrepancy?
73, Dick, WC1M
-----Original Message-----
From: Guy Olinger, K2AV <k2av@qsl.net>
To: Towertalk@contesting.com <Towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Wednesday, March 10, 1999 5:21 PM
Subject: [TowerTalk] Tower in center of 4square
>
>Anyone have any experience with a 4 square that has a tower in the
>center of it? Your difficulties, suprises, etc? Work to spec?
>
>Thanks & 73, Guy
>
>--. .-..
>Guy Olinger, K2AV
>Apex, NC, USA
>
>--
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