I have a lower mid priced power supply in my computer at the radio desk and 
it's very quiet. Even the cheap one that came with that computer was fine 
but that one burnt up. I have seen some that are bad, some that are good and 
that goes for expensive and cheap ones. It's very hit or miss. I tend to 
just look on the web sites I order from most and get the same thing I got 
before that I liked.
----- Original Message ----- 
From: "Steve" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, August 07, 2014 12:27 PM
Subject: Re: more noise


> Who knows.  Cheap power supplies aren't very well-shielded.
>
> I remember when my XYL, N7JBY, built a computer for our son.  The damn 
> power
> supply was so dirty, it produced an S9 noise spectrum across the whole
> 75-meter band.  You could even detect noise from it when the computer was
> turned off; you had to turn the actual power switch on the back of the
> computer off to completely get rid of the noise, and that was with the
> computer twenty-five feet away from the ham station on another floor. 
> Yet,
> other computers will happily run right next to the station with no
> discernible noise.
>
> Sometimes, ya gets whatcha pay for.
>
> Steve, K8SP
>
> ----- Original Message ----- 
> From: "Howard Kaufman" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Wednesday, August 06, 2014 6:29 PM
> Subject: more noise
>
>
>>I had to replace the power supply in my main computer today.
>> Now the computer works, but I have birdies all over the broadcast band.
>> Haven't turned on the HF station yet.
>> Will one of those RF line filters help?
>> Is their anything I can do besides replacing the supply again?
>> How do I know the next one won't be worse?
>> I imagine they are all switching supplies these days.
>>
>> H T Kaufman MSW LCSW
>> Adaptive Technology Instructor
>>
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