Thanks for all the replies. (For once, I actually had more mail I wanted to
read than spam in my Inbox.)
I learned some useful things from the responses, especially
1. It's OK to distribute residential power at 14.4 kV.
2. Such systems _can_ be quiet.
3. Listening to ultrasonics is not necessarily the proper way to look for RF
noise sources.
Several responses discussed how old, deteriorating, poorly maintained
equipment can be the problem. But those writers must have missed the part
of my post where I stated that the problems started when the utility
replaced everything with new stuff. "All the lines, insulators,
transformers, even some of the poles and pole locations were brand new," I
said. Actually I'd guess that _all_ the poles were replaced with new. And
to this day all the hardware looks great to my (admittedly unskilled) eye.
There's no visual sign of any deterioration or poor maintenance of anything.
So I won't be taking any "pictures of damaged insulators and document
visible rf arcing at night, rf burns on poles and hardware, damaged rotten
poles" as one reply suggested. The stuff all looks pristine to me. It was
all brand new in 1996. I live in a relatively rural area in the Southeast,
so road salt (or coal!) is nowhere to be found. Tree branches are generally
well trimmed.
One reply from Tom Rauch dismissed the utility guy's statement that the
slight unraveling of a stranded-conductor jumper could have arcing at the
unraveled point. It's possible that I could have misunderstood everything,
but my recollection of the incident (it happened that morning when I stayed
home and went around with him) was that we found a noise source
(ultrasonically), he went up in the bucket truck, used his close range
ultrasonic sniffer to identify the jumper as the noise source, replaced the
jumper, then there was no more ultrasonic noise. When he was back on the
ground he pointed to the unraveled section (happens all the time when
falling branches or ice hits the wires, he said) as the cause of the
problem. Of course, replacing the jumper didn't affect the RF noise at my
station, so the whole thing was probably a barking-up-the-wrong-tree
incident anyway.
Another message in this thread said "I've put on hundreds of miles and more
time then I care to mention driving, observing, car full of test antenna's,
analyzers, scanners, sledge hammer shaking guy wires (carefully) and logging
no less then 26 locations just inside of my community across a one mile
stretch..." Unfortunately that level of effort is completely beyond me.
Although my life has slowed down somewhat to the point where I can start
thinking about ham radio again, my job is really a job and a half, and I am
left mentally exhausted after my work weeks, filled with nothing but tough
testing and tough problem solving. I have no energy left for this kind of
thing. If this is what it takes, I'll just give up and concentrate on some
of my other, easier, hobbies.
But I haven't given up yet. Tom Rauch said in another reply "I think a
logical first step would be to locate the problems, since the utility seems
to be trying, and see if they can fix the problems." Right on. I am lucky
in that I have a utility person who is willing to help.
As I said in my first post, in 2001 I was able to quickly locate that first
source across from my house. It peaked up clearly and loudly on my portable
2M 3-el yagi with AM-detector-equipped HT. Unfortunately nothing else has
worked so easily. I've spent a fair amount of time walking around from pole
to pole and not really been able to localize anything. The noise I pick up
in my shack can be S9, but the noise on the HT is always very weak, and it
seems to be all over the place in terms of direction and location. I've not
been able to get a clear peak at a pole even once since that first time. If
I drive around in my car, (i) it never shows up on the AM broadcast band, so
I can't use that, and (ii) I can't wield my 2M beam while driving, and I
pick up nothing (except some ignition noise) on the HT's rubber duckie. So
I seem to be not too useful in the locate-the-problems department.
It seems possible, since the problems appeared when the whole power
distribution system was rebuilt, and it seems to come from many, many
sources, that the power company made some sort of system-wide error when
they put it together. Maybe something like the "taught-span hardware used
with slack spans" (I don't know what that means, of course) situation
mentioned in one of the replies.
I've just ordered the recommended AC Power Interference Handbook, by
Loftness, so I can being learning about this stuff. Perhaps it can help me,
and help my power company RFI guy. I'm going to contact him and, basically
give him an edited version of this thread and my conclusions from it.
We'll see where we go from there.
Thanks to all es 73,
W1JA
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