Many of us bought Prodelin hardline about 20 years ago, both 7/8" and 1/2"
It has worked well for many years and typically still is low loss. Recently
I found I had a lower than normal swr on my low band antennas. Also, the
resonant freqs shifted down. Turned out to be the shield was open in one of
the 1/2" runs to the tower. My cables are buried for about 20' (through a
flower bed) till they run on the surface for about 100'. Some places on the
surface the outer black plastic covering has split over the years. The
aluminum shield always looked bright. About 4 months ago I had run a power
and loss check on all the coax/hardlines and everything looked good.
I dug up the cables that were buried. The 1/2" line that had the open shield
had cracks and splits in the outer covering. The aluminum shield was gone in
several places for about 6'. There was a gel type goo between the dielectric
and outer covering.
My questions;
- Has anyone else had this happen to them?
- Is this a result of a lightning type hit?
- Is this the result of aluminum reacting with the ground?
- Could I just have a defective piece of hardline or should I plan on
replacing all of this hardline that has cracks in the outer covering?
- Maybe running it on the ground prevents or slows down the reaction, if
that is what is happening?
I can send a jpg to anyone that wants to see this.
Tnx for any suggestions.
Tony
N2TK
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