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Old September 20th 04, 06:52 AM
Richard Harrison
 
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Mark wrote:
"Is this practical?"

Trees near an antenna cause some loss. It`s hard to quantify in advance,
but in ww-2, the signal corps estimated that hf loss is usually
negligible if horizontal polarization is used (page 241 of 'electrical
communications engineering').

I`ve found that horizontal HF dipoles, directly fed by coax in various
Bolivian Chaco Jungle sites, below the the tree canopy, but not too
close to the trees, communicated well with Cochabamba and La Paz,
Bolivia. So, the dipoles didn`t suffer too much from the trees. The
Signal Corps was right.

Best regards, Richard Harrison, KB5WZI