> Speaking of flooded coax...
>
> I noticed something recently about at least one of my spools of flooded
> quad-aluminum-shield "RG-6". Since the flooding compound is only in the
> outer shield (the braid right under the outer jacket), it seems possible
> that under certain circumstances, water could still wick its way along the
> inner shield and cause degradation of the inner braid and the foil
> surrounding the dielectric.
I don't know how anyone could put flooding between the foil and center
dielectric, or why they would want to.
Quality cables have the foil bonded to the center dielectric. The LMR400 I
purchase is made that way, as are the CATV cables I've used. I can't recall
ever seeing unbonded foil, except on some old Rat Shack cable.
Also, the goo isn't a particularly good RF dielectric. Getting it between
the foil and center would change cable characteristics, and not in a good
way.
Bonded foil cable, used by almost everyone with large systems, sure is
taking an undeserved hit. Some of the confusion might be from specific
isolated cases, and not typical performance. Once something like that
happens in Ham radio, it can propagate for years as a rule.
If bonded foil was problematic or "unreliable", large system users would
avoid it. It's probably the single best change that happened to indoor or
outdoor cables.
73 Tom
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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