Memotech MTX500

The Memotech MTX500 was a British home computer built around a Z80A processor, dedicated video memory and Texas Instruments graphics and sound chips. Its black extruded-aluminium case and full-travel keyboard gave it a markedly more substantial appearance than most contemporary home computers.

Although named for a 32KB user-memory configuration, the machine included a separate 16KB of video RAM and could be expanded substantially. Memotech BASIC, a monitor and built-in commands for graphics and sound made the MTX500 capable, but its comparatively high price limited its mass-market success.

Notable Features

• Black extruded-aluminium case housed a full-travel mechanical keyboard.
• Separate 16KB video RAM left the main memory available to programs.
• Microsoft-derived MTX BASIC included extensive graphics and sound commands.

Historical Significance

• Memotech's first complete home computer after the company became known for Sinclair memory expansions.
• Combined polished industrial design with a highly expandable Z80 architecture.

Collector’s Notes

• MTX500 and MTX512 cases look very similar, so the model badge and internal RAM configuration should be checked.
• Communications boards, disk systems and original manuals add substantially to a complete setup.

Specifications

Technical Information
Name	Memotech MTX500
Manufacturer	Memotech
Launched	Saturday, October 1, 1983
Launch Price	£275
Country	United Kingdom
CPU	Zilog Z80A at 4 MHz
Units Sold
Operating System	MTX BASIC and monitor; CP/M with suitable disk hardware
I/O	RF, composite video, audio, two joystick ports, Centronics, cassette, cartridge and expansion
Keyboard	Integrated full-travel mechanical keyboard with numeric keypad
Storage	Cassette up to 2400 baud; optional FDX floppy and HDX hard-disk systems
Sound	SN76489A, three tone channels plus noise
Graphics	TMS9929A, 256 x 192 pixels, 16 colours and 32 sprites
Display	40 x 24 text; optional 80-column display with disk systems
ROM	24KB containing MTX BASIC, monitor and utilities
RAM	32KB main RAM plus 16KB video RAM; expandable to 512KB
CPU Speed	4 MHz