My response to K4XS is that in modeling my similar system I felt that his
should work fine. There is always some interaction but as you pointed out
most of us have do not have unlimited space for antenna and have to make
compromises. If you moved your 4 square a couple hundred feet away from
your tower you would likely have a skewed pattern which would be worse.
John KK9A
To: <cqtestk4xs@aol.com>, <TOWERTALK@contesting.com>
Subject: Re: [TowerTalk] 80 M 4 SQUARE MODELING
From: "Bob Shohet, KQ2M" <kq2m@kq2m.com>
Date: Fri, 21 Jul 2017 20:32:13 -0400
In 1995 I built an 80 meter 4-square with KQ2M design 3/16 wavelength
spacing
with 4 elevated Inv L elements about 50' vertical and the remainder mostly
horizontal. I used the Comtek phasing box and the antenna absolutely kicked
butt! In the 1995 ARRLDX CW Contest, at the low point in the sunspot cycle,
if
I remember correctly, I had more qso's on 80 than any other US single op.
In 1999 I put up my 130' Rohn 45 tower in the center of the 80 meter
4-square
and populated it with 3 4 L 20 meter yagis. The 4-square still worked well
but not as well as before the tower erection. Yes, that is anecdotal - but
the
effects were clear - the antenna was impacted by the tower and the yagis on
it.
I was not as loud as before and the F/B and F/S were not quite as good. It
was noticeable to me on the air in the contest - I don't know if anyone else
would have noticed the difference.
I didn't bother to model it - there was no other place to put the 4-square
or
the tower - you do what you have to do and put the antennas where they have
to
go.
Yes, the performance of your 4-square will be affected by the presence of
the
tower - but if that is the only place that your 4-square can go then don't
worry about it. If you build it properly it will work fine and you will
enjoy
using it. :-)
73 and gl!
Bob KQ2M
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