In a message dated 3/21/04 2:17:49 PM Eastern Standard Time, k1ttt@arrl.net
writes:
>>If it were true that large horizontal structures on top of
towers didn't get hit then why do power companies spend money trying to
prevent damage from strokes to power lines. HV power lines are larger
than any ham structures, within the same range of heights, and use
conductors that are often bigger in diameter than elements of large
yagis... by your 'experience' they should repel lightning, and yet they
get struck every day by both large and small strokes. <<
Just think what the power lines are:
bunch of towers with spikes on the top, prone to attract discharge.
Yes, long wires, but insulated from the towers, grounded where?
So they do not form the "umbrella" effect. The "umbrella" has to be an all
metal structure with good grounding. Power lines are not that.
I ask again, is there evidence that there were more lightning hits with large
antenna installation vs. small or pointed structures.
Yuri, K3BU.us
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See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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