Topband: deterioration of RG-6

[Pete Smith N4ZR]

I feed my 160m receiving antenna with about 300 feet of RG-6, which 
supplies power to an amplifier at the antenna.  Recently, I started 
seeing an high-resistance short across the coax (~30-50 ohms).  I took a 
junction apart and discovered evidence of current flowing across the 
double-female, as wellas some water in the connector.  I changed it out, 
and also changed both connectors on the cable, and in the process 
discovered that the braid and the first foil (it is quad-shield) appear 
to be somewhat corroded (there is a powdery grey residue that comes 
out).  I reconnected the junction, and within a few days both the short 
and the moisture were back.  In checking out the problem, I have cut 
back a couple of feet on the cable, and the grey residue is still evident.

Is water ingress a known problem with RG-6?  Any particular brand known 
to be better?  If I'm going to replace the whole feedline I might as 
well do what I can.

-- 
73, Pete N4ZR

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