There has been a great deal of going around the houses.
The original question (and the one that I believe I answered) was related to
the effect of trees.
Wood is a poor conductor. Even wet wood is a poor conductor. Even tree trunks
with sap
rising are poor conductors.
Poor conductors in the vicinity of an antenna have very little effect on its
radiation efficiency,
and are likely to have a very minor effect on the pattern. So it's usually fine
to have an antenna
close to a tree.
Lots of any lossy material surrounding an antenna (at any distance) will
attenuate the signal
from that antenna. So it's not fine to have almost any antenna in a dense
jungle, and it's not
fine to have a UHF antenna firing through foliage. And so on and so forth....
See my original post which I think explained it better.
One final thought:
It has been proposed on a number of instances in the past that the
back-to-front ratio of a
Yagi could be improved by placing an 'absorber' element instead of, or as well
as, the
reflector. (That is an element deliberately made less conductive by, for
instance, having
a resistor at its centre.) It doesn't work, and it's quite easy to prove that
it can't work.
73 Roger
VE3ZI
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