Grundy NewBrain Model A

The Grundy NewBrain Model A was a compact British Z80 computer with powerful BASIC, high-resolution monochrome graphics and unusually comprehensive interfaces. It connected to a television or monitor and stored programs on cassette, with disk and memory expansions available.

The design began at Sinclair Radionics, moved to Newbury Laboratories and was finally manufactured by Grundy Business Systems. Its long development and connection with the BBC Computer Literacy Project made it one of the most intriguing British micros of the period.

Notable Features

• High-precision BASIC included mathematical and graphics support.
• Video modes extended to 640-pixel horizontal resolution.
• Expansion modules could add CP/M disks and bank-switched memory far beyond the Z80’s native address space.

Historical Significance

• The NewBrain was once the expected computer for the BBC’s national computer-literacy project.
• Its journey through Sinclair Radionics, Newbury and Grundy reflects Britain’s turbulent early microcomputer industry.

Collector’s Notes

• Model A relies on an external television or monitor and lacks the AD’s built-in fluorescent display.
• Original power supplies, cassette leads and expansion modules are now scarce.

Specifications

Technical Information
Name	Grundy NewBrain Model A
Manufacturer	Grundy Business Systems
Launched	Thursday, July 1, 1982
Launch Price	£199
Country	United Kingdom
CPU	Zilog Z80A at 4 MHz
Units Sold
Operating System	NewBrain BASIC; CP/M with disk expansion
I/O	Two cassette, two RS-232 and expansion connectors
Keyboard	Integrated 62-key keyboard
Storage	Two 1200-baud cassette interfaces; optional floppy module
Sound	Sound available through expansion
Graphics	Monochrome graphics up to approximately 640 x 256
Display	External television or monochrome monitor; multiple 25- or 30-line text modes
ROM	24KB
RAM	32KB built in; expansion system supported up to 2MB
CPU Speed	4 MHz