Herb Johnson and Lee Hart collaborated to provide some background and general information on the diminutive Membership Card computers, as well as a number of photos:
“The 1802 Membership Card was developed in March 2005 by Lee Hart. The first few years were spent in breadboards, mock-ups and discussions within the cosmacelf online community. It's another in a four-decade series of COSMAC ELF-like computers, going back to the original ELF you-wire-it article by Joseph Weisbecker in the August 1976 issue of Popular Electronics magazine.
“Like the ELF, it has a real front panel. You can load, examine, and run program in binary with the toggle switches and LEDs. No other computer or devices are needed (people didn’t have them in 1976!). But you can connect it to a PC parallel port, and operate the front panel from it.
“The Membership Card is optimized for low power operation (under 1ma), and clock speed is adjustable from 1.8 MHz to zero. The switches and LEDs also work as a general-purpose I/O port. The small size and low power make it a useful ‘project’ computer, like BASIC Stamps or Arduinoes.
“Rev A prototypes were constructed in April 2010; rev B sold in September. Continued revisions have improved the design, added memory, and serial I/O. A protoboard has recently been added. Hundreds of kits have been built. Owners have added more hardware (Arduino shields, USB), and run both original ELF software (monitors, tiny BASIC, etc.) and new software (full BASIC, FORTH, C, etc.).”
To order your own kit, see Lee Hart's 1802 Membership Card ordering web page, which also describes some projects built around it.
For additional documentation, see Herb Johnson's support pages for the 1802 Membership Card. Herb’s site provides a wealth of information on software, hardware, owner “builds,” previous versions, COSMAC early history, and links to other COSMAC websites.
