Re: Looking for original Apple II PSU shematics

["Michael J. Mahon" <mjmahon@aol.com>]

Nama wrote:
> Right, understood. Thanks.
> The reason I wanted the schematic, and maybe I should have mentioned
> this earlier, is that a couple of the caps have fallen off and were
> rattleing around inside the box when I got it(someones previous bad fix
> I believe), and I have no idea of their orientation as it's not marked
> on the circuit board.
>
> I maybe (and thats a big MAYBE) able to figure it out though, but I'm
> no electronics wizz. It's not one of those thing you want to be wrong
> about though.

If you follow the ground trace, you'll find the polarity of the output
filter caps, as long as you know whether you're working with a positive
or negative supply voltage.  You can also follow the supply leads back
to the cap.  A continuity tester can make this easier and confirm the
result.

For the input (line filter) caps, check the polarity of the bridge
rectifier and follow traces--that will determine the polarity of the
caps.

> This power supply is #5558 and silver (not bronze), so it's an early
> one and it would be cool to get it working again.

I agree--and its schematic is very likely the one in the Reference
Manual.

> Cheers and thanks for the info.

Good luck.

-michael

Music synthesis for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

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