hum from nearby high-tension wires?

Just as I figured. You'd be amazed how many houses have bad grounds. Keep us posted on the repair.

I agree with Aball. If you have a metallic main incoming water line that should be your main earth grounding electrode. Call an electrical contractor and have him check all the earth ground connections, both ends.

Be careful messing with the earth ground connections. Sometimes a difference of potential, voltage, can exist between the ground wire/s, (grounding electrode conductor/s), and the earth ground/s, (grounding electrode/s).
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01-31-06: Steverw
>>"Jea48: maybe 80 feet high. Insulator about the height of a large owl or hawk (maybe a foot?) (I often see them sitting on the line)."<<
>>>>>>>>

Sure sounds like 69KV. No Kite flying near those lines.
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plastic water pipe. Sigh.

Turned out to be a loose connection.

There was no radio noise, even right under the wires.

But now I know a lot more about grounding, thanks for the advice.

Two things about so-called 'harmful' EMF - 1) The fields decrease at a square of the distance, i.e. if you double the distance away from the line, the field intensity goes down by 1/4, triple the distance 1/9, etc. So while there is detectable electromagnetic radiation below the lines, its pretty weak at ground level. 2) If EMF from power lines causes cancer,etc., why isn't there any epidemic among power company Lineman (there isn't). And no, I don't work for an electric utility. But there is No solid proof of EMF from power lines being harmful (unless, of course, you come in contact with one and are grounded)...