Hi Bill,
That was/is exactly the case and what has been done at my QTH since the
November weekend of 1995. Prior to that I had shunt fed my 120' Rohn 25
tower. I have my home with a 65' high mulberry tree alongside, together
with other neighboring trees that obsured nearly 50% of my tower.
I simply jacked the tower in two at the 65' level, inserted a homemade
insulated section, extended the tower to a full 1/4 WL above the insulated
section, added four 1/4 WL caged radials going out to the top of 55' wooden
poles (visualize a simple 1/4 WL 2 Meter GP enlarged 80 times), matched up
the 32 Ohm feedpoint and I had an instant winner.
Try it. You will like it. 73 de Milt, N5IA
----- Original Message -----
From: <Cqtestk4xs@aol.com>
To: <topband@contesting.com>
Sent: Sunday, October 24, 2004 7:04 PM
Subject: Topband: Elevated ground planes
> Something to think about....
>
> Suppose we have a location which is surrounded by trees perhaps around
fifty
> feet tall. Since verticals are affected according to ON4UN by
obstructions to
> some degree, wouldn't a 1/4 wavelength vertical with a ground plane at
around
> 50 or 60 feet probably be a better performer (assuming it has maybe 12 1/4
> wavelength radials) than a ground mounted one with maybe 30 or 40 radials
of the
> same size? Is it a correct assumption for 160?
>
> Bill K4XS
> _______________________________________________
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>
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