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AC Power Line Noise - Stop The
Madness
It's just plain awful. The buzzing racket that just won't go away except on rainy
days and Mondays, constantly covering up the weakest of signals (the ones you really
want to hear). Line noise is an insidious form of amplitude-modulated arcing noise
produced by corona discharge around high voltage insulators and arrestors attached
to the local power service delivery grid. Although some types of buzzing noises
can be produced in your own house (see publication #10) and
even in your own equipment (see publication #48), most crackling
and banging noises are from overhead power lines, usually the high voltage (3KV-10KV)
wires.
Can it be dealt with? You
bet, and here's how. First, recognize that electric power companies are
busy places with lots of responsibilties. If you call and whine with your
problems they may help you and they may not. They're not really responsible
for small noises you have tolerate and there are usually more important
priorities for work crews. So it's a big help to them and to yourself if
you can provide them with critical information that will help locate the
problem and hasten the cure.
First, listen to the noise
on a receiver switched to the AM mode and rotate an antenna around if available,
searching for the noise peak on the S meter. Getting a fix on the location
of the noise is extremely valuable information. After locating the direction
or if no directional capability exists, walk or drive out in the
immediate vicinity or peak direction with a portable SWL receiver or AM
BCB receiver. Listen for the loudest peak of the noise as you travel back
and forth, trying to center the peaks on a certain location. If you
are able to reach a verdict on a certain pole or locale, use a pair of
binoculars and see if you can find an insulator on the pole's crossarm
that is either arcing or is discolored from arcing, Compared to the coloration
of the rest. If the pole has a guy wire give it a shake and see if
the noise changes in pitch or stops altogether. Record the pole number
and notify the local power company of your findings. Never, ever,
ever try to climb the pole and fix the problem yourself. It's illegal and
dangerous almost beyond belief! When contacting the power company ask the
switchboard operator who handles noise complaints and follow the company's
procedures. Sometimes they will ask you to fill out a noise form with pertinent
information. Do it, and try to be personable and diplomatic. Remember -
they don't HAVE to help you, and they're human. They may just write
you off if you're a noisy nuisance. You need them but they don't need you,
and they don't have competitors. Be patient and helpful anywhere you can.
Another trick that can be
employed in your search for the noise is to look for it at dusk when arcing
is more visible. A corona discharge is often a faint blue haze around
a dirty or broken insulator. If anything like that is evident, record the
street location and the pole number (the latter is usually found on a metal
band wrapped around the pole about 6 feet above the ground).
Want to protect against
further noises or future trouble? Here's a trick method of
performing a power line noise audit. Use a CB radio in the car on
a quiet channel during the daytime and go up and down all the streets in
your vicinity out to a distance of about 1 mile from your station.
Hunt for small noises and record their positions, pole numbers, etc. Forward
the information to the power company and see if they will act on the report
over a period of weeks. A simple undertaking like that will provide you
with years of quiet enjoyment with only a small time investment.
Better yet, it's all free - even the instructions!
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