On 8/24/2017 6:25 AM, Keith Dutson wrote:
Turns out that lightning is also a major factor here. A close strike feeds
secondary arcs to the tower and coax cables. These arcs can penetrate the
coax jacket, creating pin holes that allow water intrusion.
Right. Good engineering practice is to bond the coax to the tower top
and bottom. And control cables should be bypassed to the tower top and
bottom. The principle is to put the cables and the tower at the same
potential along their length.
Heliax is not ruined by this intrusion.
This is definitely NOT true. I rescued some 7/8" from a microwave site
that has the burns to prove it! The reason it was there to be rescued
is that it WAS ruined by a strike -- the inside of the shield was
carbonized!
73, Jim K9YC
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