GEC 4100 Computer

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This computer came from the Baker Street complex that controlled the process for the London Underground, including the timetables and the emergency systems.

There were three systems, nicknamed Mummy Bear, Daddy Bear and Baby Bear, installed in Baker Street. This machine is Baby Bear, and controlled the Bakerloo line.

The machine was attached to a large console with the operator, and was connected to an HP1000 machine like the one on display on the left as you enter tha main gallery.

The machine had a long life, being in service from 1985 to November 2021, when it was decommissioned and transported to the centre.

The arrival of the more powerful 16-bit 4000 series in 1973 gave GEC Computers a basis for a much wider attack on the market. The opportunity to build on the 4000 series was helped by two important factors - public sector bodies, such as the Post Office and universities, are directed to buy British; and it had a ready made market within the GEC group, whose members are encouraged, although not compelled, to buy from GEC Computers.

GEC Computers traditionally has strong links with the university market, providing front-end computers for the ICL 1900as well as stand-alone machines. More recently its involvement with the EPSS packet-switching system and Prestel have involved a number of Post Office contracts for 4000s. the order book for 4000s stands at 260 systems with 200 installed.

We are grateful to the staff of Baker street for their extensive tour and knowledge of the systems, and London Underground who arranged the budget and transport for the machines to the Centre.

Manufacturer: GEC
Date: 1985

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Other Systems Related To GEC 4100 Computer:

Item Manufacturer Date
GEC 4000 Computer GEC 1973
GEC 4080 Computer GEC 1976

This exhibit has a reference ID of CH70098. Please quote this reference ID in any communication with the Centre for Computing History.


GEC 4100 Computer

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