"With regard to the ENIGMA engine. This was an encryption/decryption machine used by the Germans during the second world war. At the start of every day the operator would set the dials at the top to a new code number. Before starting each new message, the reset button was used to return you to the initial state. Then you typed your message on the keyboard letter-by-letter. Every time you typed a new letter, the Enigma machine responded by giving you an encrypted version. So if you typed A, on one day it might respond with C, the next day it might respond with R, and so on. And of course the next time you typed an A, you’d get a different letter, so if you typed AAA you might get CZR …

Usually you had the message written out on paper – one person typed the message in letter by letter while another wrote down the ensuing coded version. Once you had coded your message in this way, it was transmitted by radio using Morse Code. At the receiving end, the incoming Morse code was written down as the coded message, and then this coded message was fed back through an Enigma machine letter by letter to decrypt it.

The item in the picture corresponds to a more recent model. You can see the code wheels used to set the day’s code in the upper-left of the base unit. Just above the keyboard are the displays for the coded letters – each circle has a letter and a light behind it, so when you press a key on the keyboard a corresponding letter lights up.

In the lid – toward the bottom – you can see a coiled up power core used to plug into a light fitting. Also in the lit – toward the top – you can see a spare display block with cable and connector – the connector could plug into a socket on the side of the base and the auxiliary display could be used by a second operator, so the first operator could be typing the message in while the second operator was observing the coded message on the aux display and writing the coded message down – the coded message was then transmitted in Morse code.

One of the first true electronic computers – Colossus – was created in England to crack the Enigma code. You can read more by going to the following web page: http://www.diycalculator.com/cool.shtml and then scroll down to “The History of Calculators and Computers” topic and then click on the “First Electronic Computers” link (make sure you have pop-up windows enabled) and then click on the “Alan Turing, Tommy Flowers (Colossus)” link."

Clive "Max" Maxfield

X-Number World of Calculators