It started Saturday Morning... I was inspecting the property and something
didn't seem right on the first power pole at the edge of the property.
The power company had unknowingly to me replaced my mechanical meter with an
electronic meter. It doesn't appear to be a type of meter that can be
electronically interrogated. It is very small, about half the size of the
orignal meter and as it is set up now, only reads off KWh.
I've taken careful measures to ensure non of my equipment generates RFI and
now some idiot has installed God knows what on my land.
First, I checked around the pole and meter with a low frequency AM receiver
covering 180-400 KHz. There was a disasterous buzz around the meter, pole
and lines leading away from it. I checked the other poles and the box on
the house, no better.
I went downstairs and fired up the HF rig. NOISE! Every 120 Hz from 30 KHz
to just under 8 MHz! It almost has a pulse-width modulation sound to it and
it changes with load on the line, it MUST be the meter. On my Kenwood
TS-570D with 10m rotatable dipole, it was S9 on the meter. This won't do.
I picked this area when I was working on a radio telescope project for a
college, arcing power lines are bad enough, now this!
I didn't sleep that night, mulling it over in my head, thinking of my
contacts at the utulities Commission and the FCC and how to not only get
this meter removed, but all within hearing range, then how to sink the
corporation responsible. They are contracted to provide power at 60 Hz-
ONLY.
I head out the next morning and inspect things again. Odd, the noise stops
just below 4 MHz. My wife heads out with me. We inspect every square inch
of the power system, even find that we can track power lines buried four
feet under wet earth by the noise. There could be some improvements to our
system, but that is irrelevant. New meter = noise. It wasn't there a
couple of days ago, neither was the noise.
I head back down to the shack and spin the dial. I head upstairs and start
unplugging things that were never a problem, just in case. We flip
breakers, just in case. The noise is still there.
I leave the shack with the radio on, something I have rarely done.
I flip off the lights, the noise stops! I say a long string of obscenities,
then holler for my wife to come down. I tune the radio for maximum noise.
I tell her to hit the light switch. IT'S GONE!
Now then, what caused this sudden noise when for a decade there was none,
the only thing that changed was the new meter!
I think back. I changed a light bulb from a small CFL, 60W equivelent to a
100W equivelent, but I've run up to a dozen of these in the shack without
any noise. I unscrewed it just in case, no change. I unscrew another CFL,
several years old, never caused a problem. No change. Finally the third
and last CFL. The noise stops! I screw it back in, the noise is back!
I chose this particular brand and model because it was RF quiet. Suddenly
it started generating hash, every 120 Hz up to 8 MHz!!!
I will make a recording and get some screen captures of the spectrum this
bulb produced and it will be available for anyone interested, just ask!
Kurt
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