Many large commercial towers use "spline balls" for protection. A spline
ball is an object, usually oblong in shape, with hundreds of sharp points.
They are put on the tower in many places, maybe 10 or 12. The theory is
that the ground charge is dissapated into the air so that the potential
never rises to cause the upward leader that results in the large downward
discharge. This is why a tower with many uhf, vhf antennas, which result in
more discharge points, is less likely to be "hit" than the tower with one
HF antenna.
de Norm N8RGR
At 08:14 AM 8/18/99 -0400, you wrote:
>
>I've seen several posts in the past praising the virtues
>of 'porcupines' to 'drain off charge' before a strike can
>occur. I've also seen at least as many claim it is all
>bunk. I must admit it seems reasonable, but not if a
>lightning rod 'attracts' strikes. I have no background
>here - just a software guy! Does anyone know where
>I can find out about any studies, etc. to what the
>scoop is?
>
>-Brian n8wrl
>
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>
>
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