H8 Running C/PM at System Source

Heathkit H8

Date Acquired:
Sales Brochure:
Bruce Stuck via Douglas Wise

Heathkit's H8 is an Intel 8080-based microcomputer sold in kit form starting in 1977. The H8 was similar to the S-100 bus computers of the era, and like those machines was often used with the CP/M operating system on floppy disk. The main difference between the H8 and S-100 machines was the bus; the H8 used a 50-pin bus design that was smaller, more robust and better engineered electrically. The machine also included a bootstrap ROM that made it easier to start up, including code for running basic input/output and allowing input through a front-mounted octal keypad and front panel display instead of the binary switches and lights used on machines like the Altair 8800. The H8 was a successful design but required a separate terminal to be truly useful; Heathkit introduced several terminals as well.

Bruce Stuck built this unit as a kit in 1978. He wrote "When at the Letterman Army Institute of Research in San Francisco, we used an H-8 to detect and determine position of a moving target on a terrain board simulator and acquire quite a bit of pursuit tracking performance data as degraded by various levels (and wavelengths of laser glare). We used the CPM operating system as opposed to HDOS."

In December 2017, John Sutley restored the machine to working condition. He cleaned the contacts on the power switches, replaces some capacitors in the disk drives, and replaced some 7400 series TTL chips that drive the LED display.

We have a large amount of original documentation and software