Hello Jim et al.,
I will try to briefly answer your questions and then elaborate. The 3 year
delay was due to my inability to positively locate the source. (I’m just not
that good.) No, the utility did not ignore me. I did have to locate it myself
(I always do). I located it this year on January 5th, the utility RFI
Inspector confirmed and wrote it up on the 6th, and it was fixed on the 8th.
(He’s known me for 5 years and we have a very good working relationship due to
(I think) my high hit to miss ratio. I find the source, he confirms it and
writes up a real problem, and then he looks good to his upper management.) The
utility was very cooperative, and I did not have to involve outside people.
Having said all that let me expand for the rest of the story. First, the
layout of my neighborhood here is problematic. I have 1960ish build 16kV
lines/poles directly across the street from my home. They run north/south and
east/west for blocks. Near the coast, with the saline marine air, this
hardware is at the end of its design life. These poles have the troublesome
old porcelain Bell insulators, some of which have been replaced by the newer
polymer types. The rasp was very low level, almost at the noise floor. But
due to the abundance of 16kV poles, it was the proverbial needle in the
haystack. 80 meters was the worst, 40 meters was bad, 20 meters was annoying,
and the noise many times even made it up to 17 meters. Surprisingly, heavy
rain did not reduce the noise. For the first 3 years, it proved impossible (at
least for me) to get a reliable fix on it. The noise was so low level it was
inaudible on my Sony 7600 portable with tuned 2 ft loop. I could not get a
reliable fix with a VHF aviation band portable RX with 3-element tape measure
beam. I found my Arrow 5-element 440 MHz beam and Yaesu portable lacked
adequate sensitivity (the noise power at those frequencies is much lower, and
to answer your question David I would say 200 ft would be a rough guess for
maximum range on 440 MHz, line of sight of course) I had previously tracked
down and rectified numerous 16kV PLN issues in my neighborhood. Almost all
were bad Bell insulators, a few post insulators were bad, I found one sparking
cutout, one bad tie wire, and another was a broken tie wire cable clamp. I was
fairly experienced in locating PLN issues. But the nature and sound of the
rasp was different. Its constancy, low level, and character did not fit the
typical pattern of previous PLN signatures. So, I focused my attention on my
adjoining neighbors and the neighborhood, looking for the usual suspects like
LED lights, a noisy WiFi hotspot (by Ruckus) power supply, cable modems, FiOS
gear, invisible dog fences, dirty Raptor guards, a plasma TV on standby, a bad
streetlight ballast, neon signs, etc. I suspect my big break came from
corrosion. I speculate the guy wire to ground wire contact became corroded
enough to cause the noise to act up with the wind. This created a specific
noise. (It didn’t do that previously.) That noise started in December 2015.
With a unique signature (rather than just a rasp) it was a fairly quick process
to use the Sony with the loop and then the VHF aviation portable to localize it
to a general area. While investigating one 16kV pole, the 440 MHz beam led me
across the street from where I was to another 16kV pole. Standing about 20
feet from the base of that pole, I aimed the ultrasonic pinpointer almost
straight up at the Bells but got nothing. Then came the revelation. As I
lowered the pinpointer from an overhead aim to the ground it groaned. Raising
it back up just above the horizontal it groaned again. I was astonished, as it
was pointing at the guy wire of the pole. Then I noticed the guy wire was
touching the bare secondary support cable. And I saw the misplaced insulator
tube. I was not sure this was the source of the rasp, but when confirmed with
the 440 MHz beam, it was certainly the source of the noise when the wind blew.
After it was fixed, I realized it was also causing the rasp for the last few
years. In the end, I realize I got real lucky. Hope this helps.
73, Chris
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