Wild Weasel. The SAM Suppression Story

RADAR — a term that was an acronym of Radio Detecting And Ranging, named for a device that transmitted radio frequency energy waves and received reflections or bounce backs (echoes) of the radio energy waves in order to locate an object in the path of the transmitted radio waves.
Knowledge of radio waves has been with us since the late 1800s but it wasn't until 1904 that a use other than communications was discovered. In that year, the German scientist Christian Hulsmeyer demonstrated a crude radar receiver, actually an interference detector, for locating ships on the Rhine River. In 1922 American scientists used the same theory to set up a similar detector on the Potomac River. In 1925 the Americans discovered that an airplane flying through a radio beam could also be detected, and by rotating the antenna, they discovered that the direction or bearing of the object could be determined.
By 1930 there was sufficient interest in both radio and its ability to locate objects, that the United States Army began a development program on radio location at the Signal Corps Laboratory at Fort Monmouth. New Jersey. On 14 March 1934 a pair of US engineers developed the first 'pulsed' radar beam. Simply put. a radar beam is 'pulsed* by switching the set off and on. With a pulsed beam, it was possible to locate an object, not only in direction but also in range (distance) by measuring the echo, or bounce backs. In December of 1934, engineers Taylor and Young observed their first radar echoes, one of the most important engineering feats of the 20th Century.
Radar would be used for detecting and locating both friendly and enemy aircraft and ships, and to guide lost air and sea pilots to safety. Radar could be used to first locate, then pinpoint an intruder; after which highly accurate targeting information could be fed into the defenders artillery fire control system. The first demonstration of this use of radar came in May of 1938 when the US Army Signal Corps connected a newly developed radar set. the SCR-268, to a floodlight battery and picked out airplanes in the New Jersey night sky with amazing rapidity. Aftera thorough evaluation of the SCR-268. and favorable results, the Signal Corps and Westinghouse began develop­ment of the US Army's first early warning radar set. the SCR-270. In August of 1938. an SCR-270 mounted in a bomber, successfully located a patrolling B-17 seventy-eight miles away. With detection at that range, and considering bomber speeds of the period, defenses would have at least thirty minutes to react.