dsc00027a.jpg

A box containing the Enigma machine's rotors in the Enigma machine display.

The sign reads

How the Enigma Machine Works

The Enigma machine did not actually transmit a message. Its job was was to scramble a clear message into a formidable code that was then transmitted over the radio in Morse code.

Setting the machine to begin to code or decode a message was a complex process. It involved an officer to choose 4 of 7 rotors for the day, adjust them, and place them into the machine in correct order. He also had to set the plugs on the front of the machine in their correct order. The radio operator then used a series of codebooks and work sheets for determining a beginning rotor position before he could begin to work on the message.