![](https://coimages.sciencemuseumgroup.org.uk/242/484/large_thumbnail_1984_0535__0001_.jpg)
Logic door from a Ferranti Mark I computer, 1951
1951
1951
1950-1959
1930
1953-1955
circa 1985; circa 1985
1930-1950
circa 1985; circa 1985
1945-1955
1933-1938
1950
circa 1946
1928-1939
circa 1946
1925-1950
1954
1930
1933-1937
1930-1950
1945-1947
1925-1950
1950-1956
1945-1948
circa 1952
circa 1956
1935-06-24
1953-1955
1954
1928
1956-1958
1940-1970
1983-1985
circa 1985
1930-1960
1938
1952
1950
1953
1932
1936
1951-1953
1954
1925-1940
1925-1935
1930-1950
1945
1948
1950-1956