> There is another theoretical concept as dirty as it is that when you use
> longer than 1/4 waves for a 4 square, you may not get as clean a pattern
due
> to the higher mutual coupling between them. I thought that 4 1/2 waves in
a
> 4 Sq should give a better pattern. My preliminary Eznec tries were not
> good.
I modeled a 4 square of 1/2 wave verticals on EZNEC and it worked
fine with one caviat: if you want to feed the verticals
at the bottom, you must use voltage sources. Having said
that, I suspect this would be very sensistive to stray
capacitance if you actually built it, so what I would do
is feed the verticals in the center with a current
balun and bring the feedlines horizontally to a phasing
box in the center supported by a 1/4 wave mast. The
mast would have to be insulated from ground and there
would have to be choke baluns at the top and bottom of the
coax running down the mast to keep it from screwing
up the pattern. All in all, probably not worth all
the trouble.
Rick N6RK
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