On Mon, 21 Jan 2002 "John Petrich" <petrich@u.washington.edu> writes:
>
> I personally have questions whether verticals installed
> on the ground between houses or strung up parallel
> to a tree trunk are as effective as verticals installed
> in the clear - open spaces or roof tops.
Tree trunks have little or NO effect on HF antennas.
My 80M wire vertical in the woods was 'good enough'
to work XZ0A at sunset on the Long Path.
I was NOT able to get through to XZ0A using my elevated
GP antenna 70 ft NORTH of a 55 ft tower with 4L15 and 5L10
Yagi's top loading the tower which I "assume" was acting
as a non-resonant reflector giving a low but finite F/B to
the GP. The GP works EU and JA just fine.
A wire vertical 50 ft west of a 50 ft tower plus TH3 at a
previous QTH was a KILLER to the Pacific but sucked
into Africa so I expect the parasitic reflector phenomen
is a real concern when mounting verticals near other
towers / antennas.
IF you have only one, tower, using the TOWER as
a shunt fed vertical or elevated GP is a GOOD solution.
See my article on Elevated GP antennas in JUNE 1994
QST or the ARRL Handbook or Antenna Book.
Tom N4KG
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