Date: Thu, 3 Jun 1999 11:38:55 -0400
From: "Howard Aspinall" <100646.144@compuserve.com>
Subject: LF: Noise problems
To: rsgb_lf_group@blacksheep.org
Message-ID: <199906031140_MC2-780F-88E2@compuserve.com>
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John,

It sounds like it could be a power distribution problem, possibly an arcing
insulator or even a transformer, though insulator problems are often
affected by the type of weather (ie) dry, damp or wet.

Having once been in the electricity supply industry my recollection is that
although procedure now differs from company to company, in general their
stance with radio amateurs is that if the amateur can identify the source
of the problem such as the relevant tower or pole, they will effect
remedial work. Otherwise you might have to wait until the problem turns
into a failure, or it is found during planned maintenance. Power companies
did and still might operate a planned helicopter line checking procedure
following hv o/h lines with special detectors to identify hot spots/arcs
etc.

Of course if you could ascertain there are problems with reception to
"protected services" such as bc, pmr or emergency, the local RIS would
probably act. Your best bet there might be with reception problems with lw
Radio4 if you could show people were having them. Once my lw R4 reception
was completely wiped out by a switch mode psu without adequate input
suppression causing noise to be radiated along the mains wiring to everyone
being fed from that particular substation. Switch mode noise does have its
own identifiable characteristic though. I DFed the source using a portable
marine df rx with a sig meter, told the guy that peoples' reception was
affected, let him hear the noise for himself, and he sorted it out double
quick. In that case the guy was using industrial equipment from home, and
was concerned to keep people happy in case someone complained and the local
authority found out about what he was doing and charged him a business rate
or forced him to close his business. The annoying thing was the "noise
generator" remained energised even when he wasn't actually working.

If all else fails, I think you'll have to DF the source, difficult though
that will be, but I feel you should try to observe any variations in the
noise (eg) times, wet or dry weather or any other characteristics which
might give some clue as to the source (eg) factories or workshops etc open
or closed. 

Good luck

73..Howard/G3RXH