EMIDEC 1100

It used magnetic-core memory and transistor technologies and it is claimed to be the first large commercial transistorised machine in the UK.

Because transistors were relatively slow at that time, Hounsfield also used magnetic logic units to speed up the operation of the machine to achieve a processing power comparable with a valve/tube computer.

These logic units consisted of a single ferrite ring (toroid), with up to fifteen connections to it.

Anything else was stored on 1-inch-wide (25 mm) magnetic tape mounted in the vertical drive, vacuum-sealed behind a glass door.

24 EMIDEC 1100 computers were sold to commercial customers including Domestic Electric Rentals, Boots, British Motor Corporation, Kodak, London Transport, Barclays Bank and the Admiralty.