Join TNMOC volunteer Jerry M as he elaborates on one of TNMOC's oldest residents - the Harwell Dekatron Computer, affectionately known as "The WITCH". In this talk, Jerry will explore the history and significance of this incredible machine, before explaining how the W.I.T.C.H. is programmed today.

The presentation will begin with an introduction to the W.I.T.C.H., offering insights into its origins, functionality, and its role in computing history. Jerry will then dive deeper into how the computer is programmed, with a demonstration of a specially designed emulator written by Jerry himself.

About the speaker

Jerry used to write software during his day job, in areas such as retail systems, cryptography and internationalisation, for a global computing company. Since his retirement, he now volunteers at The National Museum of Computing (TNMOC), which is situated within the Bletchley Park Campus.

There, he talks to visitors about, inter alia, EDSAC, the W.I.T.C.H., and the Museum’s slide rule collection. He takes an interest in other early computers and also crypto systems such as Enigma and the Lorenz SZ42 and the breaking thereof.