[TowerTalk] Crappy LMR600

[Jim Brown]

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