PET power connector/voltage regulator

From: Anders Carlsson (
Date: 2007-03-24 18:31:40


Today I have picked up a box full of various PET/CBM motherboards,
ranging from 3000, 4000, 8000 to a few PET-700 boards. I also picked
up a few matching internal keyboards for the 3000/4000/8000 series.

Currently I don't own a single, working PET so I can't test these
motherboards, but they were all marked as OK fifteen years ago, so
I hope some of them will still work today.

The idea is that we're a bunch of vintage computing people who are
going to have a local repair/mod group. I believe we together will
be capable of building our own power supplies and some video circuit,
of which there are a few different variations on the 'Net, including
one by Nicolas Welte.

Now, I have found schematics on Zimmers for the 8032 voltage regulator.
The corresponding images in the other directories (2001N, univ. board)
are broken, so they don't display at all. Am I safe to assume that the
3000 and universal boards have the same pinout on the power connector,
so one could use an external power supply and build some extra circuit
to generate the required voltages: +5V, -5V, +9V unreg, +12V, +16V?

I did grab a lot of technical docs/specs/schematics on the PET too,
so perhaps most of what we need to know is available among the docs.
We'll see later exactly what we can do with all this stuff. If we
manage to build our own PETs, I'll take pictures of the lot.

Anders Carlsson

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