I have started design work on the next generation of DigiComp computers - the DigiComp IV. This will be a 4x4 design that can count up to 15, not just 7. Basically I have just added another flip-flop and another I/O bank to the existing computer. There's really no theoretical limit to how big you could scale this design - just add a motor drive, and you could have your own mini-Harvard Mark I.
This is based on the Minds-on Toys version, but I may use some design elements from the original plastic version. I am working on a cardboard prototype to make sure everything fits, but once I get that worked out, I would prefer to build it out of plexiglass. I would also love to see a Steampunk version of the DigiComp, with all the brass, chrome and rivets showing. Stay tuned.
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