The Lorenz Web app and the Excel Sheet below give a historically accurate simulation of the Lorenz tele-printer cypher attachment as used in World War 2. Letters typed on the tele-printer were encoded and sent using the 5-bit Baudot code. In this system, "A" is represented as 11000, "B" as 10011, etc. You can use the following app to lookup the Baudot representation used in this simulation.
The SZ 40 Lorenz machine would add a seemingly random new letter to each letter of the message to generate the encrypted message.
The SZ 40 Lorenz machine would add a seemingly random new letter to each letter of the message to generate the encrypted message.
You can use the Lorenz SZ40 web app here.

lorenz_sz40_simulator_beta6.xlsm | |
File Size: | 1876 kb |
File Type: | xlsm |
You will need Excel 2016 or later. Macros must be enabled to run Lorenz.
The best place to be is the incredible resource at http://www.virtualcolossus.co.uk/ to learn about this incredible machine and to play with a virtual recreation of the first electronic computer (Colossus) used to crack the codes.