[BC] RF absorption by foliage

[David Joseph]

Somewhere I have a copy of a military operating procedure using a tree as a 
transmitting antenna, and/or trees situated in such a way as to produce a 
DA.  Will try to find it.  My docs show a toroidal inductor around the 
trunk, at certain heights, to couple the RF.  Other articles I've seen use 
the shunt method (feed attached to a nail/spike in the trunk).

A ham friend used the toroid method and I actually heard his 100 watt 
signal, on 75 meters, from Reno, NV to the SF bay area one night.  All 
variables considered, at minimum, it might have been just the toroid I heard 
(*very* weak signal on that night).  One local in Reno on frequency refused 
to acknowledge he was hearing a tree...of all the nerve!

Dave Joseph - CBRE CBNT
W7AMX

------Original Message------
Message: 26
Date: Sun, 30 Oct 2005 21:27:16 -0500
From: "tosenkowsky at prodigy.net" <tosenkowsky at prodigy.net>
Subject: Re: [BC] RF absorption by foliage
To: broadcast at radiolists.net
Message-ID: <380-220051013122716951 at M2W069.mail2web.com>
Content-Type: text/plain; charset=iso-8859-1

>There was a station in Denver that the consultant swore was affected by a 
>line of trees less than a mile away. When the trees were in full bloom, the 
>pattern went "out" ... and when they dried up, the pattern "settled."

Trees absorb water. What you have are additional 'towers' in the array.

Tom Osenkowsky, CPBE

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