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 Home > LEO Computers > Lyons Electronic Office (LEO) Archive > LEO Artefacts Collection > Leo III Logic Board

Leo III Logic Board

One of the many logic boards that would have been installed in a LEO III computer.

Board no: S101/30N1/3; S101/30P2/3
Serial no: S006756

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

The first Leo III was completed in 1961, not long before the company was merged with the English Electric Company, which not only broke up the team that had done so much for the UK computer industry, but also marked the decline of the computer industry in the country.

Incredibly some machines were still in use in the General Post Office until 1982.

Manufacturer: LEO Computers LTD
Date: early 1960s

Related Topics:

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Leo III Logic Board Articles:

Item Manufacturer Date
Barry Hooper, Programmer Shell Australia Unknown
Hackney Archives Unknown
Higher Systems Unknown
Steve Farrow: Interview Leo Computers Society Unknown
Graham Briscoe: Reminiscence Unknown
Dick Cromwell: LEO Memories Unknown
Ray Dawson: Reminiscences Unknown
Mike Finlay: Memories of LEO Unknown
John Simon Florentin, Computer Operator Unknown
David Holdsworth: Reminiscence Unknown
Maurice Bonney: Memoir LEO Unknown
Ron Marshall: Reminiscence Unknown
Peter Mills: Reminiscence Unknown
Ray Smith: Reminiscences of a LEO III Operator and Intercode Programmer Unknown
Anthony Robin Davies: Commentary LEO Unknown
Mike Tyzack's story with Leo computers Unknown
Faith Van Rooyen Unknown
Harry Warner: Reminiscence Unknown
Emil Gottwald: Reminisence LEO Unknown
Pat Whitaker: Commentary Unknown
Norman Witkin: Memoir of working with LEO in South Africa Unknown
Denis Hitchens: Reminiscence LEO Unknown
New Computers for the Post Office Unknown
Joe McNulty: Memoir LEO Unknown
Chris Reynolds: Memoir LEO Unknown
Mike Smith: Memoir LEO Unknown
Michael Wilson: Commentary LEO Unknown
Andrew Wylie Unknown
Nigel Furness: Reminiscence Unknown
I Love ICL Unknown
Museums Victoria, Melbourne Unknown
Peter Baker: Reminiscence Unknown
John Fletcher: Reminiscence Unknown
Brian Grimshaw: Reminiscence Unknown
Penny Woodward: Reminiscence Unknown
Chris Parker: Comment Unknown
Alison Taylor: Reminiscence Unknown
On-line Leo III User Manuals Unknown
Brian Skillen: Memories of my time operating LEO I Unknown
Explore our LEO Computers Collection Unknown
Electronic Computers in the Office 1956
Introducing LEO III 12 Aug 1960
Computers for Shell-Mex and BP 1962
Current Developments in Commercial Automatic Programming 1 Aug 1962
Wythenshawe: The Second Computer Centre for Shell-Mex and BP 1963
The Management of a Large Commercial Computer Bureau LEO 1964
An Introduction to Compiler Writing Jan 1965
The Brains Behind The Buttons 5 Jan 1967
LEO III/7 Fire Sep 1967
LEO III: a rave from grave 4 Sep 1975
Interview with Les Turtle 1990
London’s Home Movies 2003
Timesharing History: the UK Story 2004
Report on visit of inspection to LEO III/ in Edinburgh Museum 2007
LEO Computer Reunion 2010 18 Apr 2010
Tony Morgan: Interview Leo Computers Society 8 Nov 2011
John Daines: Interview Leo Computers Society 26 Apr 2012
LEO Computers in Australia LEO 2013
Software, A Progress Report on the LEO III Intercode and Master Routine Emulator LEO 2013
British transistor manufacturers in the 1950s 2016
Derek Jolly: Interview Leo Computers Society 11 Apr 2016
Patrick Blakes: Interview Leo Computers Society 27 Jul 2016
Peter Bird: Interview 6 Sep 2016
Tony Earnshaw: Interview Leo Computers Society 16 Feb 2017
John Page: Interview 11 Apr 2017
A Virtual LEO III 2018
Brian Mills: Interview 27 Feb 2018
Brian Hobson: Reminiscences LEO 18 Dec 2018
Software - LEO III 2020
Michael Hancock 2020
Michael Guy: LEO Master Routine 2020
John Daines: Reminiscence 2020
Robin Davies: Reminiscence 2020
John V Panter: Reminiscence 2020
Tom Brooks: Memoir LEO 2020
John Gardner: Interview Mar 2020
Greg Wojtan: My Days with LEO 2021

Magazines RELATED to Leo III Logic Board 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 III Logic Board:

Item Manufacturer Date
Leo II Valve Rack LEO Computers LTD June 1959
55625 Program Wiring Subset Unit from LEO III LEO Computers Ltd c1965

This exhibit has a reference ID of CH52240. Please quote this reference ID in any communication with the Centre for Computing History.


Leo III Logic Board

Click on the Image(s) For Detail


Introducing LEO III
LEO III/7 Fire
A Virtual LEO III
Software, A Progress Report on the LEO III Intercode and Master Routine Emulator
A LEO III: 21st Century Hindsight
LEO III Software Rescue
History of the Leo III Software Preservation Project: Blow by Blow Account
LEO III: a rave from grave
On-line Leo III User Manuals
Report on visit of inspection to LEO III/ in Edinburgh Museum
"Check Everything”: Validity and Correctness in LEO III
Ray Smith: Reminiscences of a LEO III Operator and Intercode Programmer
Software - LEO III

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