[allowed] Re: [TowerTalk] Ground radials

[Didier Juges]

I am not sure I would agree with that statement. The purpose of the ground 
wire network is to reduce resistive losses in the ground. The wire has an 
effect of reducing the resistivity of the ground under the antenna, on a 
macro basis. If you use insulated wire, you loose the benefit of 
conductivity between the wires and the soil, which overall will increase 
resistivity compared to non-insulated wire.

For instance, below is a wire (to the left) and 2 points in the ground (the 
X's, marked A and B)). With insulated wire, the resistance between A and B 
is purely driven by soil resistivity. With non-insulated wire, the current 
will jump from A to the wire, then travel through the wire up to the point 
closest to B, then jump to B through the soil. The overall resistance 
between A and B will be lower with non-insulated wire, so the losses should 
be less.

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|   X (A)
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|   X (B)
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73,
Didier KO4BB

At 07:37 PM 12/22/2003, Gene Smar wrote:
>Tom:
>
>      Electrically it doesn't make a difference whether the wire's insulated
>or not.  Mechanically, the insulation gives you a significant degree of
>protection against corrosion and eventual disappearance of the radial wire.