How to use the M-209 portable mechanical cipher machine unit

Here is the training video used to teach soldiers how to use the M-209 portable, mechanical cipher machine unit.

This lunchbox-sized cryptographer was primarily used in World War II by the United States Military, even remaining useful in the Korean War.

One of our messages in the hands of the enemy may lose a battle, but if that message is cryptographed, the enemy will lose enough time figuring it out to make the information useless. To help you cryptograph more effectively, this converter, the M-209, has been put into use throughout out the Army. There are several models of the M-209; all operate the same way. To see how, let’s encipher...