This subject has been discussed here plenty of times in the past, and the
consensus has always been that trees and other foliage near a 160m antenna
has a negligible effect on the transmitted signal. That's what I have
believed for some time.
In this case, K9LA was talking about two things:
1.) the high voltage areas being very near foliage
2.) a dense foliage near high voltage areas increases loss a noticeable
amount
Certainly the first thing makes sense. Having a high electric field (the HV
end of the antenna) in the middle of fairly dense foliage adds loss. From my
own experience, a large pecan tree 5-30 feet from an element in my four
square raised the feed impedance of that element several ohms. That problem
went away, and the feedpoint of that antenna matched the other verticals,
when the tree was removed.
The problem is with #2. The article does not explain how the dense foliage
was created in the model, and why it would likely model like a real forest.
I'm not especially fond of someone's models of someone else's proposed
models, that can get a little sketchy in translations.
73 Tom
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Topband Reflector
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