I mentioned a while back about replacing the LMR-400UF pigtails due to
I was thinking that I should be able to cut the bad spots out and make
jumpers out of them, so last night I started doing a QA job on the 5
cables that are about 15 to 20 feet long.
Although they show the signs of some UV damage, the surprising part was
the pieces that were in the three turn coil that laid on the tower top
plate. There were many spots worn flat from sliding on the galvanized
surface and several pigtails had multiple spots that had worn through to
the braid. On the surface the braid did not appear to be corroded on
several although it had dulled in color. On two others there appeared to
be some corrosion where the braid was exposed.
The jacket had dulled but was still flexible, although it appeared to
have lost some of the elasticity as it no longer slid on the braid which
was an improvement. Whether it is still usable for indoor jumpers
remains to be seen. I'll find that out when I strip the ends back.
I was beginning to think I would use a piece of LMR-600UF as the pigtail
for the 7L 6-meter Yagi, but the wear on the LMR-400UF has caused me to
change my mind and stick with the Davis BuryFlex(TM) for the pigtails. I
do think the UF versions could be used on a smooth surface, but I doubt
they'd be good much past 10 years based on the 5 year deterioration that
I see from my installation
BTW I had given one piece a double wrap of Scotch 33 tape in the coiled
portion and saw no wear on the tape or on the jacket underneath. This is
one of the pieces that was originally damaged when the brake on an
HDR-300 failed to engage when the antenna was being swung and the wind
caught it. Although a length of the jacket was split, the "tape
bandage" did it's job better than the exposed jacket on the good pieces.
I'll pass on what I find when I strip the ends back. I'd like a LMR-600
version for the pigtail, but it appears the smaller Davis BuryFex(TM) is
the best for that application so far. That and the longest rotator
loop/pigtail is only 28'.
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