A good, inexpensive PS I''ve found
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Also, are the outputs on the PC supply isolated from the power line, or is
their a potential to get zapped if the power supply goes south?
There are lots of "budget" power supply ideas floating around, but for the
beginner, why throw in the added potential for disaster?
Original Message
> Isn't it true that you always need some load on computer power supplies to
> work/regulate.
> Seem to me I read something about this in N&V some time back.
> Also how would you regulate/limit the current so not to blow anything or
in
> my case blind by the light when (not if) I short something out. Just
can't
> trust us mech types with electricity/
> I've noticed a few questions on here about power supplies and thought I'd
> share an inexpensive solution that I've found works well for me. I built
a
> supply for my own use around a PS taken from an old AT (Pentium or older)
> computer. The AT supply is a switch-mode supply that easily provides me
> with a very well regulated high current +5v (~20A, red), +12v (~5A,
yellow),
> and lower current -5v (white), -12v (blue). Blacks are ground. Usually
> there's a sticker on top of the supply with exact current ratings. You
can
> get other voltages between +12 and -12 with the addition of a simple
> regulator. I wouldn't recommend it for applications requiring very large
> amounts of power, but it works well for electronics work.
>
> They retail for about $30 (last I checked) but many times you can just
pull
> one out of an old PC you've got lying around. Just be careful when
working
> with the power switch on an AT supply. Remember that it's switching both
> sides of 120 RMS VAC across its DPDT contacts so use caution when
connecting
> the four wires! (I've got an AT switch with a black scorch mark to prove
> the point). Also, note that even though the supply has a grounding wire,
> the chassis still needs to be separately grounded.
their a potential to get zapped if the power supply goes south?
There are lots of "budget" power supply ideas floating around, but for the
beginner, why throw in the added potential for disaster?
Original Message
> Isn't it true that you always need some load on computer power supplies to
> work/regulate.
> Seem to me I read something about this in N&V some time back.
> Also how would you regulate/limit the current so not to blow anything or
in
> my case blind by the light when (not if) I short something out. Just
can't
> trust us mech types with electricity/
> I've noticed a few questions on here about power supplies and thought I'd
> share an inexpensive solution that I've found works well for me. I built
a
> supply for my own use around a PS taken from an old AT (Pentium or older)
> computer. The AT supply is a switch-mode supply that easily provides me
> with a very well regulated high current +5v (~20A, red), +12v (~5A,
yellow),
> and lower current -5v (white), -12v (blue). Blacks are ground. Usually
> there's a sticker on top of the supply with exact current ratings. You
can
> get other voltages between +12 and -12 with the addition of a simple
> regulator. I wouldn't recommend it for applications requiring very large
> amounts of power, but it works well for electronics work.
>
> They retail for about $30 (last I checked) but many times you can just
pull
> one out of an old PC you've got lying around. Just be careful when
working
> with the power switch on an AT supply. Remember that it's switching both
> sides of 120 RMS VAC across its DPDT contacts so use caution when
connecting
> the four wires! (I've got an AT switch with a black scorch mark to prove
> the point). Also, note that even though the supply has a grounding wire,
> the chassis still needs to be separately grounded.