Introduction

On August 10, 2018 I received a carefully crated DEC PDP-8 Straight 8 from a friend in Auckland who realised he was never going to restore it, and was happy to pass it on to someone willing make the attempt. 

To the best of my knowledge it is the only one in New Zealand, and after 18 months of restoration effort, I am confident it is the only working example in the country.

There are several websites that document the restoration of these systems, most notably: 

David Gesswin’s experience: https://www.pdp8.net/straight8/pdp8.shtml

And here: http://www.pdp8online.com/straight8/ps_restore.shtml?large

The University of Iowa’s restoration: 

https://homepage.cs.uiowa.edu/~jones/pdp8/UI-8/log2015a.shtml

It’s not my intention to repeat the material they have covered, and besides their systems were in a considerably better state than the one I received. Instead I will detail my approach to troubleshooting, the tools I found useful, my experience with the repair of core memory, and other tips I trust will be helpful along the way.

It is worth remembering this computer uses only transistor and diode logic. There are no integrated circuits in sight. It also uses Ov -3v logic, so don’t expect to see +5v anywhere.

My name is Brendan McNeill, and I have throughly enjoyed this restoration project. I welcome any comments feedback or suggestions you may care to make.

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