[50mhz] [VHF] Replacing coax

[N1BUG]

12 years isn't a LONG time, but you can't always know the true 
condition of coax unless you measure it.

I once went hill topping on 2m SSB/CW and couldn't raise anyone 
after hours of calling. Paranoid, I later began checking stuff. The 
50 foot run of *perfect looking* quality RG-8/U I took measured 14 
dB loss at 144 MHz! I thought it must be a bad connector, so I cut 
both of them off and installed new, good quality ones. Still 14 dB 
loss! I did an autopsy and found no signs water had ever gotten in. 
it just had high losses.

73,
Paul



John Geiger wrote:
> I went out this morning and did a visual inspection on my coax runs, and they
> all look in very good condition. No cracking on the jacket at all, and the
> jacket still looks as good as when new.  One run of RG-11 I have is 12 years
> old, but still looks great.  I don't recognize any signal degradation on the
> coax runs either, nor changes in SWR.  Now I don't have any complex test
> equipment to test the coax runs with, just a SWR/power meter built into my
> antenna tuner.
> 
> Given that the jacket on the coax looks ok, and I haven't noticed any change
> in antenna performance, is it safe to assume that the coax is still good, or
> is there an age limit for coax after which it starts to deteriorate from the
> inside?  Is there a rule of thumb on how often coax should be replaced?


-- 
Paul, N1BUG
Aurora Sentry: http://www.aurorasentry.com
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