Put the Classic PDP-8 Minicomputer on Your Shelf

A look at the PiDP-8i replica kit from Obsolescence Guaranteed by Stephen Cass.


I finally jumped on the PiDP-8i replica kit from Obsolescence Guaranteed because it had a 2020 refresh, fixing a few rough edges from an earlier kit in both the hardware and software setup. And Obsolescence Guaranteed also went to the trouble of getting custom white and brown switches made to help duplicate the look of the original front panel, albeit at a 6:10 scale that makes it much easier to fit on a shelf. (Technically, the kit emulates the improved PDP-8/I released in 1968, which was made using integrated circuits instead of the discrete components of the PDP-8).
The core emulation software is the aforementioned Simh, and some programs have been preloaded, including some of the earliest computer games like Colossal Cave Adventure, Star Trek, and most notably Spacewar!, which you can play by setting a few front panel switches and using a program written in Processing on a desktop computer that emulates a vector display. You can also try the pre-Unix multiuser operating system TSS/8, which lets users run programs in Basic and Fortran, although, be warned, this version understands only dates between 1974 and 1985.


Might be worth a quick look at an earlier post:
A hardware shelfie

Oscar’s working pi-based scale models are very good looking indeed, and easy to construct - even I could manage it!


Don’t forget the the PDP 11 can be had for $100 more.

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Oscar is working on a PiDP-10, already has nearly 40,000 switches, so maybe in a year or two there will be three.

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I have a PiDP8 and it was good fun building it. I opted to write my own PDP-8 emulator for it rather than use SIMH - more to do with learning and understanding PDP-8 code than anything else… I even checked my instruction timings against a real PDP-8 too… see this video:

I also have the PiDP11 but not yet built it - mostly time and energy (lack of) One-day…



Summer is here, energy is the same problem for me. I will soon be at the schematic design of
a 20 bit cpu ( only 20 switches on hand) and wondering who is good at going from rough notes that to physcal boards and front panel work at a fair price. All thumbs for mechanical work here.

I’m on the waiting list for the PDP-11. I haven’t done a lot of soldering so I probably won’t do it for a while but I figured I’d at least try to get one for later.