Kelly, there's no answer. Coax used indoors in a benign environment should
last forever. The same coax laying across a hot roof and exposed to daily
UV might only last a few years. I do the "loss" check about once a year or
so on all my coax -- which is one reason I leave it very accessible and
never clamp it or tie it up so securely that it cannot be easily pulled down
for the test, which I perform on the ground rather than hanging from a
tower. Since cable aging and deterioration usually begins with a dielectric
change (for the worse), a hipot (high potential) test can often be useful in
determining if the dielectric's become contaminated or has absorbed any
moisture. RG213/U passes a 5kV hipot easily when it's new...sometimes fails
the same test quickly when it's aged. Commercial hipot testers are
available surplus around here for less than $50, often. Not a bad
investment! -WB2WIK/6
> Hi all,
>
> On a related question: when is coax old? Aside from doing loss analysis
> measurements, what signs are there that coax that appears OK is past its
> prime? How often do you replace coax? Do you replace coax on a given
> schedule, with or without signs of trouble?
>
> Just curious.
>
> Kelly
> ve4xt
>
> _______________________________________________
> Self Supporting Towers, Wireless Weather Stations, see web site:
> http://www.mscomputer.com
> Call 888-333-9041 to place your order, mention you saw this ad and take an
> additional 5 percent off
> any weather station price.
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
|