Elliott 920M Computer

Technical Information

Catalogue No: C0137
Category: General Purpose
Object Type: Signal/Data Processor
Object Name: Elliott 920M Computer
Part No: MCS920M/IL322A11787
Serial No: 216
Manufacturer: GEC Computers
Division: Unknown
Platform(s): Jaguar 
Year of Manufacture: circa 1982
Width (mm):
Height (mm):
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Location: Archive Object Store

GEC Computers Limited
Title. MCS920M Digital Computer
Catalogue No. MCM7
Drawing No. IL322A11787
NATO No. 6JA-7440-99-111-8581
Serial No. 216
Joint Services Manuf. No. K0978
Borehamwood England
A subsidiary of the General Electric Company Limited


.The 920 series of computers was developed at Elliotts Borehamwood Computing Division in the 1960’s and was derived from the successful 901 commercial computer which was miniaturised for airborne use. One of the primary production derivatives was the MCS 920M which was used in the
Jaguar Navigation and Weapon Aiming Sub-System NAVWASS This system comprised the MCS920M central digital computer, E3R inertial platform, projected map display and horizontal situation indicator together with the necessary power supply, electronic, interface and control units.
The MCS 920M is a microminiature general purpose digital computer using flat pack integrated circuits and. has a random access, 8192 word, 18 bit ferrite core store with a 2microsecond cycle time. Elliotts lacked access to multi-layer printed circuit board technology so used a special technique developed at the Borehamwood Computer Laboratory (see ‘Moving Targets’ by Simon Lavington). The box is unusual in that it folds out into three blocks.
In addition to performing navigation and weapon aiming calculators, the computer caters for in-flight monitoring, initial alignment and in situ first line system testing. The Computer also had an Interface Unit which enables the digital computer to receive and transmit information from and to other units in the aircraft in compatible signal form. The Interface Unit also supplied the power for the computer and Navigation Control Unit.
In its production form the MCS920M was widely used in its intended role in the Jaguar navigation attack system and eventually grew to a 64 K machine. Yje 920M also saw use in the ELDO rockets.
The MCS920M was also adopted for a number of naval inertial navigation applications.

This Unit is Serial No. 216 and was made at Borehamwood in 1982

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