On 7/4/2012 9:10 AM, Bill Cromwell wrote:
> Hi,
>
> I have been limping along with a really ugly replacement power supply in
> my big computer. It's networked (think of internet tools). I could hear
> *nothing* on my radios aside from the racket made by that power supply.
> I even found my power supply listed on the internet as an example of
> *ugly*. There is no EMI filter at all - just two jumpers where the
> filter is supposed to be. The computer had to be turned off to even
> think of using a radio.
>
> I have paid for a new, better quality power supply (only $2 more) and
> the online tracker suggests it will be in my mailbox any minute..maybe
> tomorrow. I got impatient. I have two of those ugly supplies so I took
> the filter parts out of one of the dead ones and installed them in this
> one. I put the supply in the computer and it made quite a difference!
> It's not good enough yet but I am listening to hams on 40 meters while I
> am typing this! I couldn't do that before. Next I'll be getting my hands
> on some ferrite core materials and looking to see just how far I can
> reduce the noise.
>
> I have two laptop computers here, older and newer, and I can barely tell
> when I turn either of them on. Neither one talks to my network at the
> moment so I will have to correct that. But I have a "target" noise
> performance for my PC tower, now. Meanwhile I have the noise knocked
> down well enough to try using this computer to help with operations
> while on the air. I may be unable to hear the weakest signals but I'll
> see how that goes.
>
> 73,
>
> Bill KU8H
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
Hi Bill!!
Just for reference, my HP generates NO noise. It is possible to get
clean supplies, although I can't tell you what is in this box. This was
purchased as a complete unit and came through a government purchasing
source available to employees. You might also want to try a UPS between
the computer and the line. I have had that help me in a couple of cases.
--
Kim Herron W8ZV
1-616-677-3706
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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