The RCA COSMAC 1802 “Membership Card”

Computers & Mobile
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You may have seen this little beauty floating through the interwebs. It’s an Altoids Tin-based COSMAC Elf, built around the classic RCA COSMAC 1802 microprocessor. It’s the prototype to a kit that Lee Hart has been developing. P. Todd Decker (Overland Park, KS) sent us a link to this video of his build of the kit prototype. He writes:

I have completed a build of Lee Hart’s “COSMAC Elf Membership Card.” The idea behind Lee’s design was to create an interesting kit to introduce new people to the classic RCA COSMAC 1802 historic microprocessor. This processor has a long, interesting history and is even still used, due to its unique properties when it comes to power and durability. It was the basis for the famous “Elf” home-built computers from the late 1970s. It still has a strong following. Lee’s twist on the old reliable was to rework it into an Arduino-style platform that—best of all for makers—fits into an Altoids can. His design doesn’t require any surface-mount or complicated build techniques. Herb Johnston has done an excellent job of documenting Lee’s efforts to create this kit (see link below).

Lee Hart’s 1802 “Membership Card”

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Gareth Branwyn is a freelance writer and the former Editorial Director of Maker Media. He is the author or editor of over a dozen books on technology, DIY, and geek culture. He is currently a contributor to Boing Boing, Wink Books, and Wink Fun. His free weekly-ish maker tips newsletter can be found at

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