Date   : Tue, 05 Dec 2006 21:40:12 +0000
From   : splodge@... (Richard Gellman)
Subject: [OT-ish] A3020 won't turn on

Hi,

I'm looking for the expertise of a power supply expert...

I have here an A3020 that was working fine until I switched it off, then 
back on again (not quickly, leaving adequate pause between) to check the 
cold start boot sequence.

But it didn't come back on.

The supply fuse is fine, and no burning smells are too be found. A quick 
test with a voltmeter shows that the +5V line stays constantly at 0V, 
and the +12V and -12V lines seem to *very* slowly build up (about 0.01V 
every 10 seconds for -12V, 0.01V every 1.5 minutes for +12V).

The power supply itself looks to be a linear type (there is only one 
huge transformer and a single toroid coil present), unless its a very 
deceptive looking switch-mode supply. There doesn't seem to be a -5V 
test point, so I assume it doesn't require one.

Anyone have any ideas?

-- Richard