> I have recently replaced some "RG-6" in use for maybe seven or eight
> years.
> I opened it up to see what was happening. The degree of oxidation on the
> inside and outside of the foil was perplexing. One could easily draw a
> thumbnail along either side and build up a little pile of oxide. The foil
> itself had become very brittle. It had been "sealed" and treated outside.
Use flooded cable outside.
> If Jim says the shielding needs help when it's new, there's not much hope
> for some varieties when it gets old. Another reason not to use anything
> other than the flooded variety. Particularly so for someone who can look
> at the ocean. I'm hundreds of miles from salt air. Would need to go with
> flooded for sure close to the ocean.
CATV F-6 or F59 cables are great for 160, or any HF band use. I use ten's of
thousands of feet of the stuff, much of which has been installed in the
early 2000's.
My trunk cables are primarily flooded hardline, stepping down to F-11 style
(F does NOT mean flooded, it is for F connectors) flooded cables for
distribution, although some F-11 runs are thousands of feet. The longest run
of F11 is about 3000 feet, and it is dead quiet when terminated.
I have measurements on my webpage of F11 excited by overhead dipoles, and I
can say with 100% certainty any claims of meaningful shield leakage are
simply not factual.
The same is true of smaller F6 cables.
The only potential worriesome issues I have seen are lightning melting
shields. This happens when ground loops create large strike currents in the
shields. For example, when my towers get a hard whack from a superbolt, the
common mode current can follow trunks out to my vertical array. That array
has eight 150-foot buried radials on each of eight elements, and currents
that massive wide-area ground will occasionally melt a shield on F-6 cables.
Other than that, Racoons, and mowers, F6 through F11 has been flawless. This
is true in working systems and in actual measurements.
73 Tom
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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