CPU Z80A at 4MHz
Text 40/80 x 25/30 (black and white), AD model had internal 16 character vacuum fluorescent display
Graphics 256/320/512/640 x 250
2 tape ports and floppy disc
2 serial ports
Three models were available. The "A" only had a tv/monitor output, the "AD" had a 1
line by 6 character VFD, and the "M" had the VFD and a battery pack. There are three stories of it's origin, one is that it was offered to Sinclair who turned it down
another is that Sinclair sold it when they failed to get the BBC contract.
A third story is mentioned in
the "Sinclair story" by Rodney Dale. He says that first Sinclair
microcomputer contained some innovative design concepts, but the National Enterprise Board (a
major shareholder) sold
the design to Newbury Electronics to raise cash for Sinclair Radionics.
After two years, the machine was rescued by the British Technology Group who
placed the design and production in the hands of the Grundy Group.