Path: utzoo!attcan!uunet!ingr!proctor
From: proctor@ingr.UUCP (John Proctor)
Newsgroups: sci.electronics
Subject: Re: Whispering wires
Summary: CORONA
Message-ID: <2272@ingr.UUCP>
Date: 27 Jun 88 12:51:03 GMT
References: <3025@mit-hermes.ai.mit.edu.AI.MIT.EDU>
Organization: Intergraph Corp. Huntsville, Al
Lines: 23

In article <3025@mit-hermes.ai.mit.edu.AI.MIT.EDU>, jpexg@mit-hermes.ai.mit.edu.AI.MIT.EDU (John Purbrick) writes:
> I was out in the country a few days ago and passed under some high-tension
> wires. The power lines were emitting a sort of hissing, crackling sound,
> with no detectable 60Hz component that I could hear. What causes this effect?
> If it makes a difference, the weather that day was very hot and fairly humid.

What you heard is corona discharge. The same principle applies to 
electrostatic discharge from any conductor. Dirt, temperature, humidity
all come into play in determining how severe the problem is. It will
generate broad spectrum RF noise from the am band up beyond 30 MHz. If
it was severe let the power company know they might be interested, but
not usually. 


John D. Proctor		|  Usenet: {ihnp4,uunet}!ingr!jdp!proctor
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