W8JI wrote:
>You would NEVER get away with "sealing" 9913 in GA and
>keeping water out. It probably is fine in Arizona, however.
>
>The only way I can think of the be safe in a humid climate is to
>flood the first few inches of cable with RTV after filling it with dry air.
>
>Problems are proportional to length and the "drop" in the cable, as
>well as local climate. If you have a flat run that is short, even if it is
>a mild leaker, you likely won't find a pool of water no matter how
>hard you look.
>
>If you have a 160 foot vertical drop, water will pool at the bottom no
>matter how you seal the stuff, short of plugging the ends with a few
>inches of RTV after purging it with dry air!
>
>Hollow cables without dry air pressure are a dumb idea. The loss
>decrease is very minor over foam, and no matter what you do it is
>unlikely you can seal a cable so good with air so dry you never
>have a problem, desert areas excluded.
While I think LMR-400 is a much better choice than 9913, water
ingress is caused by improper weatherproofing, period.
Proper weatherproofing WILL keep the water out - it'll also keep
it IN of course. Keeping a reel dry until it is installed is the
larger challenge in my view.
--
Steve K8LX
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