[Lowfer] PC noise source; I was surprised

[Andy - KU4XR]

Hi everyone:

My PC noise woes are no longer a problem. And when I found the
problem, I got a bit ticked off. I spent a pretty penny on the
ORION power supply from HP in the UK. Advertising had it hyped
up to be a super Industrial type power supply. Clint described 
it in his post. The frazzlin thing had NO::: input filtering
whatsoever, not a stitch. All the places for the components
were on the board, but when manufactured; the caps were left
out, and where the chokes were supposed to be was bypassed with
with straight wire. I brought home 3 power supplies from work
to switch out, and a dead one for parts. SMPS have always made
me a little leary about working on them, but I figured what the
heck, it'll either go, or blow. I took the input filter parts
from the dead supply, and installed them in the ORION supply.
Plugged it in the outlet, no kaboom, flipped the switch on the
supply, the light dimmed for a split second; but no kaboom.
And finally the smoke test, pressed the power button on the PC
and::: no kaboom, just a nice boot up, and heavens to betsy !!
no noise !!!! I tuned around and found the noise still there
but down at 497.80 KHz, AND !! dropped 20dB in intensity.
No noise in the lowFER band, ran the ham bands thru 30 meters,
and just a couple of very narrow spots on 160, and 80 meters,
none on 40 meters, and 30 meters was as quiet as if the PC was
turned off.

A couple of other tid-bits; - - before fixing the power supply;
I replaced every power cord in the house with the shielded ones,
and it did make a difference actually to my surprise. No more
TV hash now, and all PC's but my daughters made no noise.
I forgot that I had put the same ORION supply in her PC too.
I swapped it with one I brought home that was well filtered,
and had the shielded AC input plug. Turned her PC back on,
and Wah-Lah !!! noise gone !!!  I'm sitting here now looking
at the S meter and seeing the lowest noise level ever with
3 computers, and a HDTV set going. 

Gentlemen; again I want to say thank you for the wealth of
information you guys have shared with me while trying to find
the culprit. Now, I am looking forward to actually doing some
listening with a chance of hearing something.

73 to all from Friendsville, TN.


Andy - KU4XR - EM75xr - Friendsville, TN.
LOWfer Beacon " XR " @ 185.29866 KHz ( QRSS-60 )
Coordinates:  N:  35* 43' 54" - W:  84* 3' 16"
http://www.myspace.com/beaconxr
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