Experiments with various CPU's

One-gallon computer. The two-gallon model was pre-empted by IBM's introduction of the PC.

Plywood computer based on RCA's CDP1802 CPU.

Digitport, a device for entering bytes into the computer, considerably faster than eight toggle switches.

Operating system (or monitor) written in machine language, input from digitport.

Z80 based raster generator with storage for four frames.

Z80 based cp/m machine, 8" dual floppy drives, Xerox820 motherboard. When motherboards became cheap, reinventing the wheel got more appealing.