Diana Moon Radar
September 1958 Radio & TV News

September 1958 Radio & TV News

[Table of Contents] Wax nostalgic about and learn from the history of early electronics. See articles from Radio & Television News, published 1919-1959. All copyrights hereby acknowledged.

Earth-Moon-Earth (EME) communications have been used by amateur radio operators for a few decades now, made possible by more capable transmitters and receivers as well as digital encoding which facilitates operation closer to the noise floor. EME is regarded largely as a novelty branch of Ham radio since relatively few people are set up to exploit it. In 1946, the U.S. Army Signal Corps created "Project Diana," named for the Roman moon goddess Diana, as an experimental exercise to bounce radar signals off the Moon and receive the reflected signals. It was the first attempt at radar astronomy and was the first time a terrestrial radio signal was bounced off another celestial body. Once artificial satellites were orbiting in the late 1950's, Hams and other entities were encouraged to detect and track orbits and signal transmission properties - including frequency and power - to aid government engineers and scientists in determining stability (electrical and mechanical), speed, rotation, altitude, path, atmospheric and cosmological noise sources, and other parameters. In order to reward Hams for their efforts, QSL cards were issued to anyone who took the trouble to report reception incidences. The first QSL cards issued for satellite reception reports was by the Russians during the Sputnik flights in 1957.

Diana Moon Radar

Amateur radio operators who successfully pick up signals from outer space during calibration of the satellite-Minitrack stations can now show cards acknowledging their reception. Before launching of U. S. satellites, the giant transmitter and antenna of the Diana moon radar at the U.S. Army Signal Research and Development Laboratory at Fort Monmouth bounce 108-mc. signals off the moon. This is done so that the far-flung Minitrack stations and amateur radio operators can calibrate their receivers for precise tuning to the transmitters aboard the U.S. satellites. When hams receive the moon-bounced signals, they notify the Laboratory at Fort Monmouth or the American Radio Relay League at West Hartford, Connecticut. In appreciation of their assistance, the Army sends each reporting amateur a customary acknowledgement or QSL card - the first one ever issued for picking up signals via the moon.

Posted August 18, 2020