Hum problem solved

Sun Apr 13 07:47:15 EDT 2008

If there is a green pigtail ground wire on the outlet strip's power
cord and the pigtail wire has a spade lug on the end that you are
supposed to place under the head of the screw that secures the cover
plate to the wall outlet, the spade lug might have been touching the
head of the screw. To do an effective job of  reducing hum in audio
equipment, the pigtail wire doesn't have to carry much current--maybe
only microamperes. As a result, if the lug had merely been touching
the screw head, it could have been sufficient for hum reduction--until
something ever so slightly disturbed the ground wire's position.
That's all it would take.

Dan Strassberg (
eFax 1-707-215-6367

----- Original Message ----- 
From: "A. Joseph Ross" <>
To: <>
Sent: Sunday, April 13, 2008 12:53 AM
Subject: Hum problem solved

> The stereo and some other components are connected to an outlet
> strip
> which, instead of a three-prong plug, has a two-prong plug, plus a
> wire that is intended to be connected to the screw holding the
> outlet
> cover plate.  It wasn't connected.  I connected it, and everything
> works fine.
> What I don't understand is why it worked previously.  If it was
> connected before and came undone, I would think the screw would have
> been looser than it was.  I'll probably never know, but the problem
> is solved.
> Again, thanks to all who responded with their suggestions.
> -- 
> A. Joseph Ross, J.D.                           617.367.0468
> 92 State Street, Suite 700                   Fax 617.507.7856
> Boston, MA 02109-2004          

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