Re: Building computer - power supplies
On 09/27/2013 09:21 AM, Ralf Mardorf wrote:
/snip/
> However, undersized voltage for capacitors for switching power supply is
> an often used fraud against consumers and switching power supplies
> pollute the mains. Exotic resistors sometimes make them a PITA when you
> want to repair one and you don't have those resistors on stock. I
> dislike all switching power supplies.
>
> Regards,
> Ralf
>
>
Not sure what you mean by "undersized voltage for capacitors." Good
enigineering practice says that there should be plenty of headroom on
capacitor voltage rating. IOW, if you're filtering a 15 volt supply,
you shouldn't use a 16 volt capacitor, but at least a 20 Volt one.
Or more. MIL-specs require double the working voltage, in most cases.
While it's true that switchers produce RF interference, that can be
handled by proper shielding of the supply and filtering of the AC line,
usually using ferrite components. Modern power supplies for sensitive
radio receivers are designed using switching techniques and proper
filtering, and the receivers work without interference.
A further point: Common computer supplies are rated around 450 Watts.
You wouldn't want to lift the transformer that would supply 450 Watts,
much less take up the space for it. So switching supplies are the only
reasonable alternative.
--Doug, retired electronic engineer and radio amateur, WA2SAY
--
Blessed are the peacemakers..for they shall be shot at from both sides.
--A.M.Greeley
Reply to: