... and yet one more project for me, reviving an old LSI 11/03

So this is what the mystery box contained …

An interesting contrast between the ends of a computing spectrum; a fully populated Unibus frame from a LSI 11/03 (but no case/PSU) and a BBC Micro:Bit with a breakout board.

(Also a high speed paper tape reader (RS232 output), that I have no idea what use I can put it to.)

My elder brother (the donor) tells me that the LSI 11/03 worked (with the replacement PSU) when he last used it … 30 years ago.

But it least it comes with a comprehensive collection of books/manuals and a spare CPU board (but no software). So I think I have a good chance getting it running again. (Though I might need some help connecting a terminal.)

I need to finish a few projects I currently have on my small workbench before starting a new one, which will give me time to research exactly what I have got here, and make a plan for slowly setting it to work again.


Just to confess a momentary confusion on my part - this here is an 11/03, whereas you mentioned fixing up an 11/20 in your intro post:

But that’s a machine you no longer have… so you hope to get back to running a PDP-11, which is surely a worthy goal!

Yes, that second DEC machine was a PDP 11/20, one of these:-https://images.computerhistory.org/revonline/images/x1507.98p-03-05.jpg?w=600
Quite big, very heavy and a bit noisy.

So this LSI 11/03 will be my third DEC machine.

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I always wanted a brother. Now I know why :slight_smile: