Harry Welsch was a notable German cryptographer and mathematician during the Second World War. Not much seems to be known about him. Norwegian Enigma expert Frode Weierud would like to change this. Can my readers help?

Two years ago, I published a list of all German WW2 encryption machines I was aware of. Meanwhile, I have some new information. Here’s an update.

On September 21, 2018, a reconstructed Turing-Welchman Bombe will try to find an Enigma key, just as it did during World War II. Deciphering experts will use this key to decrypt eavesdropped Enigma messages. The whole event will be live streamed on the internet.

Fritz Menzer was one of the brightest German cryptologists of the Second World War. A number of important points in his biography are still unclear. Can my readers solve these mysteries?

On Wikimedia, photographs of a number of lesser-known encryption devices from Switzerland are available. Can a reader tell me more about them?

The Siemens & Halske Geheimschreiber (T-52) was the second-most im portant encryption machine of the Germans in World War II. George Lasry has recently published a few computer-based attacks on this device.

A Reddit user has posted photos of an unusual machine, the purpose of which is unknown. Some say it might be an encryption machine. Can a reader tell more about it?

The Enigma breaking machine “Bombe” had a considerable impact on the course of the Second World War. A recently started crowdfunding campaign aims to create a new Bombe display area in Bletchley Park.

In the Second World War, the Germans constructed a voice encryption machine. I have only very little information about this device. Can my readers help me to find out more?

A store in Peekskill, New York, has an interesting encryption machine on sale. Can my readers help to find information about the background of this device?