Developed in 1939, Telefunken introduced the Wurzburg A air defense radar, which operated at 560 MHz with a 3 meter (9.8 ft) parabolic antenna, had a range of 28 miles, and enabled the tracking of aircraft height, distance, and baring to guide night fighters attacking Allied bombers and to direct anti-aircraft guns and searchlights. To improve range and accuracy, the Wurzburg Riese, or Giant Wurzburg, used the same basic electronics with a larger 7.4 meters (24.3 ft) antenna and a more powerful transmitter, extending its range to 44 miles. Constructed by Luftschiffbau Zeppelin GmbH with the same lightweight alloys and construction methods as its 1930's airships, the Giant Wurzburg was too large to be fully mobile and was mounted on fixed bunkers, rail cars, and in at least one case aboard a ship, while its electronics and operators were housed in a shed on the azimuth mounting that turned with the radar. First deployed around Berlin in 1941, it was the most powerful radar in use until the SCR-584 was introduced by the U.S. Army in late 1942, and by the end of World War II about 1500 Giant Wurzburg radars had been deployed around Germany and nearby industrial areas to aid in the destruction of Allied bombers. After the war, many were taken over for scientific research; some were brought to the U.S. for studies of the Sun and used as radio telescopes to map the Milky Way. In 1947, three Wurzburg antennas, including the one at the National Electronics Museum, were installed by the U.S. Bureau of Standards in Sterling, Virginia, to research solar noise and sun spot phenomena, and in 1952 they were moved to Table Mountain near Boulder, Colorado, where they continued in research. This Giant Wurzburg is the only remaining example in the U.S.; others were destroyed or returned to Germany. Two Wurzburg Riese radars were used together with systems such as the Freya early warning search radar, with one tracking incoming bombers and the other tracking and controlling interceptors.
