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Re: [TowerTalk] trees and verticals

To: "" <>
Subject: Re: [TowerTalk] trees and verticals
From: Roger Parsons <>
Reply-to: Roger Parsons <>
Date: Wed, 28 Dec 2011 07:50:38 -0800 (PST)
List-post: <">>
Eddy and others

I am a little unconvinced by some of the arguments that have been presented. 

Consider a Yagi in free space with nice copper elements. It would work quite 
well if one could find a way to connect the transmitter.

Now consider replacing one of those copper elements with one made out of wood. 
Because wood is a poor conductor, very little current would be induced into it 
from the driven element, and to all intents and purposes the Yagi would become 
one having one less element. The pattern would (probably) be distorted because 
of the missing element, but the efficiency of the array would be almost 

By extension, keeping all the original elements in place, and introducing an 
additional wooden element into the array (even if resonant), would have very 
little effect because the current induced into that wooden element would be 
negligible. This is a close parallel to having a tree near an antenna.

The question of whether it is good to have an antenna in the middle of a forest 
is completely separate. If we put our nice Yagi into a big wooden box, it will 
not work so well because there is now a lossy medium through which the wave 
must pass. The thicker the walls of the box and the more conductive its 
material the greater its effect will be.
73 Roger

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