Heathkit H11
| Industry | Electronics, Computer kits |
|---|---|
| Products | Heathkit H11 computer kit |
The Heathkit H11 Computer represents one of the pioneering personal computers offered in kit form, launched by Heathkit in 1978. It was essentially a miniaturized adaptation of the Digital Equipment PDP-11 system. As one of the earliest 16-bit personal computing devices, it was marketed at a price of US$1,295. Functionality depended on connecting an external terminal and storage device, which confined its market primarily to hobbyists familiar with Heathkit products. Its premium price and specialized target audience led to its discontinuation by 1982.
Specifications
Key features of the H11 included:
- Processor — LSI-11 (KD11-HA module)
- Clock speed — 2.5 MHz
- Read-only memory — maximum of 8 kWords (16 KB)
- Random access memory — expandable up to 32 kWords (64 KB)
- Expansion slots — 7 available Q-bus slots
- Storage options — H27 8-inch floppy drives (two single-sided units with 256 KB capacity each) or paper tape
- Input/output interfaces — serial (RS-232) and parallel connections
- Operating system — HT-11, a streamlined variant of RT-11
- Instruction compatibility — aligned with PDP-11/40
- Programming languages supported — including BASIC, Focal, among others
While the initial memory capacity restricted software availability, upgrading RAM to 32 kWords enabled operation with various PDP-11 operating systems and peripherals, facilitating seamless integration within the DEC Q-bus architecture.
See also
External links
- Heathkit H-11 Computer – Heathkit Computer Advertisements, Decode Systems
- Computer Museum – Depiction of a fully expanded H11 bearing the Heath/Zenith branding