On Sun, 13 Dec 2009 17:55:45 -0800 (PST), b
put finger to keyboard and composed:

I eventually traced the cause to a partially shorted spindle motor.
Changed that and the beast works, but I am concerned that the bridge
rectifier (marked GW RS202; appearance-wise, its like number 2 in
this pic http://arcadecontrols.com/BBBB/bridges.jpg ) gets extremely
hot in operation (you can't keep a finger on it at all). Not sure if
that is normal; the pcb looks slightly scorched near there, so could
have always been this way for all I know. The other identical bridge
is pretty much cool in use.

So, question is, is this likely to be leaky? I've only ever had one
case of a similar leaky rectifier, in a VCR a few years ago. In my
experience they normally just short out. Maybe fit a beefier one?

I've seen several instances of leaky rectifiers in linear supplies.
The ripple on the output was very obvious in my case, though.

An RS202 crosses to an NTE166 (100V, 2A):
http://www.nteinc.com/specs/100to199/pdf/nte166.pdf

Here are other datasheets:
http://www.datasheetarchive.com/sear....x=24&sub.y=12

You may want to measure the current drawn by the load.

- Franc Zabkar
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