"Rick" wrote in message
...
I have been wrestling with power line noise here for almost a year.
Power company hasn't been very successful in locating it so I started a
coordinated search.


My local utility has one tech who does power line noise investigations and
I'm happy that he solved my problem. He identified three "problem poles"
and a week later, the noise was gone.

I can't answer your question about how far power line noise will travel but,
since you've put so much effort into this already, this next may be worth
doing, too.

One of the tech's tools was an audio detector, which he aimed toward the
tops of all the poles on my block. It was a 16-inch clear parabolic
reflector with a microphone mounted at the focal point and an amplifier
feeding headphones and a meter. The tech was listening for the sound of the
offending arc. Never mind the RF -- find the faint sizzling noise by ear!!

For a small fortune, these guys will sell you one: http://www.paradish.com/

You could definitely make one. This article
http://www.solorb.com/elect/misc/bige/ illustrates the idea (from a Google
search of "big ear" microphone) and it looks like he used an old wok.
(Are woks parabolic.)

So, if you want to impress the power company ...

Sal