----- Original Message -----
From: "Mike Waters" <mikewate@gmail.com>
To: "topband" <topband@contesting.com>
Sent: Thursday, June 21, 2012 5:10 PM
Subject: Re: Topband: Chokes for Beverages
> 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.
>
> This could happen if water somehow entered the end of the coax, or damage
> (sharp rocks, animal teeth, etc.) to the jacket went all the way to the
> inner shield next to the dielectric.
Thats how I lost the RG-11 flooded decades ago.
After the bites the water went both ways and being the frugal type I
checked.... Only short lengths of 10 to maybe 40' were salvagable out of
750' as well as a pair of 200' runs to the relay box.
At least they got reused as jumpers around rotators or in the house and yagi
stack phasing lines.
>
> I'm thinking that the aluminum foil shields are plastic coated.
I doubt that, it may be a conductive assembly lube.
If that's
> the case, then only the inner braid would oxidize.
Thats where it happens but the white dust is deposited securely to the foil
in places.
>
> In this scenario, the coax would have one intact (outer) braid, and one
> oxidized (inner) braid, at least for some distance from where the water
> entered. Any thoughts on the consequences if this should occur?
A semi conductive jacket between foils or between center conductor and the
outer foil. Ive no idea what the results would be. All my feed cables are
now elevated at about 6-7' from transformer box back to the switching. This
means a 6-7' wire to ground rod 20+ feet from the box ground with 31
ferrites at both sides.
>
> And is all quad-shield flooded coax manufactured with just the outer braid
> flooded?
As far as I know.
>
> If I would have thought of this before, I might not have just laid 600' of
> coax on the ground next to a fence. But I haven't noticed anything wrong
> with the way that Beverage works (so far).
Time and luck will tell.
Carl
KM1H
>
> 73, Mike
> www.w0btu.com
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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