[Ham-Computers] hash w/o the corned beef

[Philip]

Jeff,

My experience here has shown that this interference typically comes from two 
sources.  The computer power supply and the monitor itself, with some noise 
occasionally being radiated by the mouse cord etc.  On my last computer, (a 
600MHz P3) some noise was radiated around 7MC by the mouse cord whenever I 
moved the mouse. The mouse also got QRM'd sometimes when I transmitted on 
40M, doing strange things to the cursor.  Ferrites didn't help, I just lived 
with it.  The new 3.4GHz P4 machine is very quiet, RF wise.  It's well 
shielded and has an RF quiet power supply.  The old HP CRT monitor was well 
shielded and only radiated a little.

When I had to replace that monitor I found that ALL the new CRT monitors 
that I tried out were TERRIBLE, and they went back to the store! Apparently 
they no longer bother to shield them any. The answer was to buy a nice 
ViewSonic  LCD flat-screen monitor with INTERNAL power supply (I finally 
took a portable radio to the dealer).  It is VERY quiet, RF wise.  The only 
radio that hears any QRM is the AM portable that I listen to Rush on, and 
that's because it and it's internal ferrite antenna is only a couple feet 
from the monitor.

NOTE:  NOT all LCD monitors are as quiet as this one.  The "Generic" one 
that came with the new computer has an external switching PS that does 
create a few "Birdies", but not excessively so.  I let the wife use it with 
the old 600MHz P3 for her Email.  But if the need ever arose I wouldn't be 
averse to putting it here in the radio room.

73 de Phil,  KO6BB
DX begins at the noise floor!

THE BEACONEER'S LAIR:   http://www.geocities.com/ko6bb/
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Merced, Central California,    37.3N  120.48W  CM97sh


> My computers are wreaking havoc upon my radios.
>
> I just tried putting some ferrite donuts around the power cords,
> resulting in a zero db reduction.  I might as well have eaten them.  I
> have an indoor loop and outdoor antenna; switching makes no difference.
>
> I'm going to try reorienting them, but what other practical solutions
> are there?  I'm not limited to one room, but since I spend a lot of time
> there, I'd prefer to have radios and computers both in the room.
>
> Face it - it would be pretty silly to try tuning a radio in the next
> room.
>
>
>
> Thanks,
> jeff