There's an article in a early 80s HamRadio that discusses this.
As I recall, the author had about a 500' run, and he describes
a 4 wire system that worked well.
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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