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Leo II Valve Rack

One of the many valve racks that would have been installed in a LEO II computer.

This is probably a Register or a store unit. It has a change label on the side dated 11/6/1959, and a number 857701A/P2.

It also has a test date of 19/5/1960 and A5 written on the label side, on the other side is another mark of ECC 91 and a tick.

Valve checking policy changed many times. transmitter/receiver would have needed regular setting up to maximum performance in the test rack. these ECC91 valves may have needed special attention.

The board is part of our onsite display for the National Lottery Heritage funded-project 'Swiss Rolls, Tea and the Electronic Office'.

LEO II computers were installed in many British offices, including Ford Motor Company, British Oxygen Company and the 'clerical factory' of the Ministry of Pensions at Newcastle. LEO III computers were installed in Customs & Excise, Inland Revenue, The Post Office and in Australia, South Africa and Czechoslovakia. The first was installed at Stuart and Lloyds in 1957.

Manufacturer: LEO Computers LTD
Date: June 1959

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Leo II Valve Rack Articles:

Item Manufacturer Date
Leo III Tape Reels English Electric Leo 1966

Magazines RELATED to Leo II Valve Rack in our Library

Item Manufacturer Date
The Computer Journal July 1960 Jul 1960
The Computer Journal April 1962 Apr 1962
The Computer Journal April 1963 Apr 1963

Other Systems Related To Leo II Valve Rack:

Item Manufacturer Date
Leo III Logic Board LEO Computers LTD early 1960s
Program Wiring Subset Unit from LEO III LEO Computers Ltd c1965

This exhibit has a reference ID of CH56848. Please quote this reference ID in any communication with the Centre for Computing History.


Leo II Valve Rack

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