Joan-Eleanor system

The Joan-Eleanor system (or J-E for short) was a very high frequency (VHF) radio system developed during World War II for use by agents working behind enemy lines to relay information and replaced the earlier S-Phone system used by agents.

The Joan-Eleanor system was developed from late 1942 onwards for the US Office of Strategic Services (OSS) by DeWitt R. Goddard and Lt. Cmdr. Stephen H. Simpson, with some contributions from mobile radio pioneer Alfred J. Gross. It was reportedly named for Goddard's wife's Eleanor, and a WAC Major of Simpson's acquaintance named Joan.

The initial design work was performed at RCA's laboratories in Riverhead, NY, and the production units produced by Citizens Radio of Cleveland, Freed Radio Corporation of NYC, Dictagraph Corporation of New York, and the Signal-U Manufacturing Company. Most of the testing was carried out in the USA and some at Bovington, England, beginning in July 1944, to refine the equipment with the first operational use later that same year.

The system was classified as top secret by the US military and was not declassified until 1976.

The system comprised a pair of transceivers:

The system was designed to use the VHF band, since it was known that these frequencies could not be effectively monitored by the enemy. The agent made his report in plain speech, and the aircraft recorded the transmission on a wire recorder. Since Morse code was not required, the agent did not need to be trained in it, thus reducing overall training time, which was considered an advantage in the European theater. Additionally, the aircraft could ask for immediate clarification if required, without the delay of encryption and decryption, or an intelligence officer aboard the circling aircraft could talk directly with the agent.

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