Catherine Caughey
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Catherine Mary Caughey used Colossus computers for codebreaking at Bletchley Park during World War II.
The Colossus computer, as operated by Catherine Caughey at Bletchley Park during World War II
Lorenz cipher
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The Lorenz SZ40, SZ42a and SZ42b were German rotor stream cipher machines used by the German Army during World War II. They were developed by C. Lorenz AG in Berlin. The model name SZ is derived from
Catherine Caughey
…using the Colossus computers for deciphering German High Command messages. Later she was responsible for the teleprinter room in the Newmanry, where Tunny (Lorenz cipher) messages were received from the main intercept station located in Kent. After the war, Harvey attended Dorset House in Oxford, trained…
The Lorenz SZ42 machine with its covers removed. Bletchley Park museum
The Lorenz SZ machines had 12 wheels each with a different number of cams (or "pins"). OKW/Chi wheel name ABCDEFGHIKLM BP wheel name ψ1 ψ2 ψ3 ψ4 ψ5 μ37 μ61 χ1 χ2 χ3 χ4 χ5 Number of cams (pins) 434751535937614131292623
Cams on wheels 9 and 10 showing their raised (active) and lowered (inactive) positions. An active cam reversed the value of a bit (0→1 and 1→0).
A rebuilt British Tunny at The National Museum of Computing, Bletchley Park. It emulated the functions of the Lorenz SZ40/42, producing printed cleartext from ciphertext input.