Ken Bessler wrote:
The following website has a 1M .mp3 file of some QRM
I'm getting on 160 meters. A little background is in order:

My station has my PC about 3' away from my FT-857D's.
I've eliminated all cables except video so I'm pretty sure it's
not coming from them. I've powered off my monitor and
adjusted the refresh rate to no avail. I grounded the PC's
metal case and tried it with/without the side covers. No
difference in the signal.

Tonight I looked at my CPU temp and it was a tad higher
(127 deg F) than normal so I decided to turn on a box
fan pointed at the left side of the tower case. To my shock,
the QRM faded away! I switched the fan on and off several
times to prove my theroy. Then I made the mp3 recording you
can download he

http://members.cox.net/kg0wx/index.html

Listen closely to the sound - at 2.2 seconds into the rec-
ording, you can hear the "tick" that is me turning on the
fan to "low". Within a few seconds, the QRM is gone!

Anybody know where I should look to find this and kill
it?

I had a similar problem with a new computer system I recently built up.
Problem was a noisy 350W Power Supply.

I replaced it and the machine now is perfectly quiet. A good solution
for a few bucks. It is very hard to shield a computer from this sort of
noise as it radiates from the leads in addition to directly from the case

Dick K7RNZ