Hi,
I used Davis Buryflex (RG213) on my 15 M yagis (they were put up in
1999) and I was replacing some connectors today when I noticed something
disturbing. On the PL259's on 3 of my 4 yagis;, there was a greenish
hue. I cut off the connector of one of them, looked inside, stripped
off the dlelectric and saw that the Center Conductor (CC) was blackish
and that there was a whitish/greenish powder on top of the dielectric.
The braid also had little flecks of black on it. (I have not
experienced any change in performance of the 15 yagi that had the
discolored center connector.)
Using a utility knife, I scraped off some of the black on the braid and
it was shiny underneath..
Then I cut off ~ 10' of the coax and again stripped it.
The CC had less black on it and again scraping with the utility knife
showed shiny copper underneath. The dielectric was white/green but not
powdery - it was more like a thin paper covering. What was very
different was that the BRAID was completely clean and shiny.
I soldered a new connector on and the yagi worked fine, the same as
before.
Questions:
How problematic is the blackened CC?
What is that whitish/green powdery stuff inside?
How problematic are the flecks of black on the braid?
The coax has been on the antennas for 23 years so I am probably at or
near the expected life span of the coax. Is the the coax breaking down
and that is what I am seeing?
Has there likely been any deterioration of performance? If so is it
substantial?
Even if it is, replacing the coax is not an option right now.
I would appreciate any thoughts/suggestions that you might have.
Tnx & 73
Bob, KQ2M
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