Topband: Effect of Trees

[Michael Tope]

----- Original Message ----- 
From: "EP Swynar" <gswynar at durham.net>

> My logic may well be flawed, but I'd press a nice tall tree into antenna
> service any day --- all the more so in winter, when the sap isn't running 
> &
> the tree is probably less of a conductor than it otherwise might be in
> summer.
>
> Surely a nearby tree would have have a far less detrimental effect upon an
> antenna than a steel structure would...
>
> OK, all you antenna ghurus reading this, go ahead & prove me wrong! Hi Hi
>
> ~73~ Eddy VE3CUI - VE3XZ


The counter argument to that, Eddy, is that although a metal tower
can distort the pattern, it won't neccessarily convert a large portion
of TX power into heat, whereas anything that is a lossy conductor
or lossy dielectric (like a tree trunk that is heavy with sap) has the
potential to convert RF power into heat if the coupling is strong
enough.

In any case, I think everyone will agree that a clear space free from
any vertical obstructions is the best case scenario.

BTW, I must be getting senile in my old age. I forgot all about the
Marconi that I ran in Florida that was right next to a pine tree similar
to the one I have now. The main difference between the two setups
was that in Florida I had 1/2 acre of land with a high water table and
about 2000' of radials. I felt louder at the Florida QTH running 90
watts than I do at my present QTH running 1 KW. The other culprit
here maybe the close proximity to the steel stucco mesh in two story
wall next to my vertical. I am sure that doesn't help either.

I did manage to work 46 states this weekend, so some energy is
escaping the trees, the ground, and the stucco wire -:)

73, Mike W4EF.............................