Hi Pete,
That conduit of yours sounds like neat stuff.
I assume you have periodically looked for water and seen none?
Guys forget just how much water can accumulate. They apparently have
never remove the end cap from a "sealed" beam element only to have
water pour out.
HMMM, that's way up in the air. Imagine it it were underground.
I definitely do not agree with those advocating perforated stuff.
Around here with a clay level a foot or so down, it would guarantee
water backing up through the holes and permanent submersion. Water
seeps down till it hits the clay level then builds up what an produces
a "lenticular" pool of water well above the water table. Those with
well draining soil consider yourself lucky but not typical.
Just dig a shallow hole in the spring and watch it fill up and stay
filled.
The only real answer appears to be to assume the coax will be wet.
Use coax which can stand it and consider the pipe a way to prevent
physical damage.
73 de Brian/K3KO
Pete Smith wrote:
>
> >If coax is going to sit in water why bother. They maintain it is
> >impossible to keep moisture out of the pipe and it accumulates with
> >time. They suggest one design where the PVC pipe it it high in the
> >center and tips either direction into dry wells at the end. Even this
> >design has problems when ground water table rises to the ends of the
> >pipes.
> >
> >What is real world experience with this?
>
> I have had ALL my tower-to-shack cabling in 2 x 3" PVC conduit buried under
> maybe 4" of dirt (acros my side yard in WV) for 5 years. Absolutely NO
> problems. To be fair, mine has a very distinct one-way pitch, so water
> retention is NOT a problem. This conduit is the stuff used for TV cable
> and utility wiring, with thick walls and a silicone lining for easy
> cable-pulling.
>
> 73, Pete N4ZR
> Contesting is!
>
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