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Old March 4th 04, 08:54 PM
Richard Harrison
 
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Dave wrote:
"The standard method is wire ties and is quite adequate for tower
bases."

I lost count decades ago on the towers I`ve installed. The peril is
high-density current directly through concrete which always contains
moisture which has not yet reacted with the cement. This is still true
after a thousand years, but the concrete is still strengthening as the
reaction continues.

Solution to the lightning vulnerability is to bypass the tower base with
multiple high-conductivity paths. It`s customary to attach a heavy
copper cable to each tower leg and route these cables outside the tower
base to their individual ground rods. You don`t do this on a medium wave
broadcast tower as 120 radials are ground enough for the tower which
rests on insulators.

Best regards, Richard Harrison, KB5WZI