At 21:04 30/05/2004 +0100, you wrote:
SMPS are always a pain to troubleshoot, and I've always opted to find a
replacement. In this case that isn't probably feasible so ---
They are a pain to troubleshoot, but they're also a part of the classic
computer, and thus should be repaired and preserved. Why do people seem
to think that 'classic computer' == 'CPU only'?
Agreed - I could easily put in a PC supply, and I even have a couple from
"slimline" PC's which would probably fit the box - however I want the
machine
to be as original as possible.
I'd
buckshot the components in the switch driver, such as the IC. Sounds
In a supply of this age, I would not be suprised if the chopper driver
was discrete transsitors.
It is - the only IC is the Opto-isolator.
Anyway - I found the problem - It was a shorted capacitor on the primary side
of the transformer - what threw me off was it was NOT one of the electrolytics...
There's another one beside it which is just like it, so I think I will replace
both.
Supply works fine now - and so does the entire machine.
(Joy at getting an old Apple clone working somewhat overshadowed by the fact
that I finally found a Kaypro today!)
Regards,
Dave
--
dave04a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools:
www.dunfield.com
com Vintage computing equipment collector.
http://www.parse.com/~ddunfield/museum/index.html