23 Jul
2007
23 Jul
'07
7:18 a.m.
On Sun, 22 Jul 2007, Josh Dersch wrote:
Hi all --
Picked up an Apple III this weekend in non-working condition, and I suspect
the power supply is at fault.
Symptoms are: On power up, a rapid clicking noise is emitted from the power
supply (maybe 4Hz or so), and the power LED on the system's motherboard
pulses at the same rate. Obviously I haven't run it for more than a few
seconds like this :).
There are no obviously bad parts (burned parts, swelled/leaking capacitors,
etc...) that I can see.
I'm mostly a software guy but I'm trying to get more into hardware so that I
can better maintain my collection as more stuff starts to break down :). I'd
like to make an attempt to fix this but I'm unsure where to start. I have
found schematics at: http://www.1000bit.net/SUPPORT/SCHEMA/a3/050-0057-a.jpg.
If anyone has any advice, I'd be most appreciative.
Thanks in advance!
- Josh
I had an Apple ][+ which did the same thing, but it was temperature
sensitive. Try warming or cooling the system before powering on. If that
works, you can heat/cool individual components to find the one that is
causing your problem. I got a replacement supply from the EBay seller, so
never determined exactly what was wrong with mine.
Clint
