[R-390] powerline noise

[Bruce Ussery]

----- Original Message -----
From: "Roy Morgan" <roy.morgan@nist.gov>
To: <r-390@mailman.qth.net>
Sent: Thursday, March 27, 2003 7:45 AM
Subject: Re: [R-390] powerline noise


> At 05:47 PM 3/26/03 -0600, you wrote:
> >My QTH has a horribly high noise level  ...
> >Any ideas?
>

My particular "horribly high noise level" was mainly below 4 Mhz; sniffed it
out using a transistor radio as mentioned in other posts and turning off
circuit breakers. Turned out to be a garage door opener. The little remote
receiver must have a dirty power supply, and the wiring going to the remote
button and safety sensors made a great transmitting antenna. Knocked it down
95% or so with an inductor in series with the remote button wire at the
receiver end, and a little cap across the remote button contacts. Don't know
the inductor value (random junkbox parts); the cap value was fairly
critical - .0022uF comes to mind but would have to check. Good luck.

Bruce
WA4ZLK