Power supply question

From: ajp166 <ajp166_at_bellatlantic.net>
Date: Sat May 12 21:30:44 2001

From: ip500 <ip500_at_home.com>


> Would a "modern" switching supply ie: a cheap, generic PC supply
>have enough output to run a vintage machine? I had considered doing that


At best the answer is maybe. Reason is I have no idea of the specific
vintage machines power needs.

For example the average PC power supply can run from 145-350 watts
and that alone covers a lot of ground. Ther other problem is most of the
PC power supplies outout is +5 and some +12, some of the vintage
machines may have heavier needs for +12 or maybe -12. Another
example is the PDP-8/f I have, a 250W PC supply would easily
satisfy the +5v needs but would fail badly as the PDP-8 wants
+15 and -15 something a PC supply cannot do.

>faulty memory] the HP drew about 20 amps or so on the +5 line. Shouldn't
>be too hard to pull a couple of the faulty cards to make room for the
>much smaller [physically] supply. Might be a problem with lack of decent
>air circulation for cooling though.
> Again from memory ... even the CE's really didn't want to fool with
>repairing the PS units on these. When I bought a bunch of HP gear there
>were 8 or 10 dead supplies that had been stashed away to maybe fix
>"someday'.


Many people are scared of PS units. Switch mode PSUs are harder
to fix than linear. Then again I fixed a BA123 supply by replacing a
failed internal fuse! So first testing and deciding how bad the failed
 unit is likely first order of the day.

Allison
Received on Sat May 12 2001 - 21:30:44 BST