IBM 5155 Power supply schematics or info

[Alberto Rubinelli - A2 Sistemi]

> Well, it shoud be until the PSU gets going :-).

Right

> I presume that delay is that 47uF capacitor charging up. So
> that's probably
> not defective.

Yes, is this delay. I have change the capacitor with a new one, to be sure
of this delay ... but with no effect

> > Maybe IC3001 or IC3002 defective ?
>
> Or the transistor is open-circuit?

The transistor (tested with multimeter) seem to be good (the two junctions
are ohmnicalli corrected)
I can try to substitute it. Now I haven't the board near me, I not remember
if is a standard NPN

> Still, you're now down to one simple-ish stage that presumably you can
> debug.

Yes , the only question is : what is the tolerance of these protections ?

> Incidentally, I should get a copy of the schematics to Dave at the
> weekend for scanning.

They are good ! very good.
I'm writing a little page with information on how to repaire this power
supply, and can complete.

Thanks

Alberto

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Alberto Rubinelli          Mail : alberto at a2sistemi.it
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