[John L Stewart]

Originally Posted by flipper

On Sat, 14 Jul 2012 09:45:27 +0000, John L Stewart
wrote:


Coincidentally, I discovered that one of my RF noise problems, in
addition to this location being an RF nightmare, was one of my PCs.
The dern thing splatters RF all over the place even when turned off, I
have to pull the plug to get it off the air, so I guess the power
supply is going out. Fortunately it's not the server.

It is the switch mode PS that generates lots of RFI, wether the PC is on
of off. Not unusual at all. I found similar problems while testing some of
my experimental AF amps in the past.

Cheers, John

Thanks. Yes, I know its the switching power supply. That's why I
speculated it was going out.

I've got a dozen PCs here and that's the only one doing it but I don't
really know when it 'started' because its reserved for testing things
and doesn't always have even the power cord connected since that's
'shared', along the monitor, keyboard, mouse, et all, with another one
I also use for testing (one is Windows 7 and the other Windows XP).

I mentioned it because I imagine there might still be people who think
'off' really means 'off' but that hasn't been the case ever since the
'soft' power button.

It took me a while to pin that particular noise to the PC because
noise here is sometimes so bad I can barely receive even the strongest
local stations and I know that's nothing in the house because I've
tripped the main breaker and had the power company out. They seemed
'surprised' there was so much noise, and confirmed its coming in on
their lines, but then informed me the power company is only obligated
to provide 'power' and not 'noise free' power.

Another common & obvious nusance is the CRT type display. Generates a beautiful comb spectrum that can really get in the way as we try to chase down some kinds of problems.

Good Luck, John