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John William Marchetti (June 6, 1908 – March 28, 2003) was a radar pioneer who had an outstanding career combining government and industrial activities. He was born of immigrant parents in Boston, Massachusetts, and entered Columbia College and Columbia School of Engineering and Applied Science (the undergraduate colleges of Columbia University) in 1925. In a six-year program combining liberal arts and engineering, he earned both A.B. and B.S. degrees, followed by the graduate E.E. (Electrical Engineering) degree in 1931. He was employed by New York Edison as a power engineer for several years, during which time he also participated in the U.S. Naval Reserve as an Ensign.〔"John W. Marchetti – Oral History," Modern Physics Collection, National Museum of American History, Smithsonian Institution (six tape cassetts, recorded Nov. 2-3, 2000)〕 ==Army - Signal Corps Laboratories== In 1937, Marchetti obtained a civil service position in the Signal Corps Laboratories (SCL) at Fort Monmouth, New Jersey. He began as a junior radio engineer in the General Development Laboratory, running tests on the SCR-300, well known as the "Walkie-talkie" communications set. After receiving appropriate security clearances, he was transferred to the Radio Position Finding (RPF - early SCL designation for radar) section where Paul E. Watson, the SCL Chief Engineer, was leading the development of the Signal Corps’s first pulsed detection system. His initial assignment was to design a 600-MHz transmitter for future RPF systems using the newly developed Doorknob tubes. In December 1937, the 200-MHz experimental equipment was set up near the coast and detected aircraft at distances up to seven miles flying in and out of New York City. In early 1938, the RPF activities were moved to a more secure location at Fort Hancock in Sandy Hook, a peninsula reaching into the New York Harbor. Watson’s initial system was designated SCR-268, and two other systems soon evolved, the SCR-270 (mobile) and SCR-271 (fixed site). Marchetti continued work on 600-MHz devices as well as on the other three systems. Before the end of 1940, all of these were placed into production and had limited deployment. During 1941, the SCL again relocated, this time to Camp Evans, a site a few miles south of Fort Monmouth. Here it was called the Evans Signal Laboratory, with Watson, now a Lieutenant Colonel, serving as the Director. One of the first SCR-270s was in service on the island of Oahu on December 7, 1941. At 7:20 a.m., the operators reported detecting a flight of planes due north, but the Duty Officer dismissed it as "nothing unusual" and the alarm went unheeded.〔Witness testimony regarding Opana Point radar; http://www.ibiblio.org/pha/myths/radar/〕 At 7:53 a.m., the Japanese hit Pearl Harbor. With the entry of the U.S. into war, most of the personnel at the SCL were commissioned into the Army; Marchetti was made a Captain. Following the surprise bombing of Pearl Harbor, there was a crash program to obtain radars to protect the Panama Canal Zone from a similar attack. To detect low-flying aircraft at a range allowing sufficient warning, a high-frequency radar system for picket ships stationed 100-miles offshore was needed. Coworker Harold A. Zahl had developed a tube (VT-158) that gave up to 240 kW pulse power at 600 MHz . (This was actually four triodes and their associated circuitry tightly packaged in one glass envelope.)〔Orr, William L.; "The secret tube that changed the war," ''Popular Electronics'', March 1964, pp. 57-59, 103-105〕 Marchetti led a 20-person team in adapting the SCR-268s for using this tube; the project was completed in a few weeks, with the first set installed on the M.S. Nordic.〔Carl, Fred; "Radar experts worked at Camp Evans to protect canal," ''The Coast Star'', June 12, 2003; http://campevans.org/articles/196-radar-experts-worked-at-camp-evans-to-protect-canal.html〕 As U.S. troops began the recapture of islands in the Pacific Theater of Operations, there was an urgent need for a portable radar to provide medium-range early-warning against aircraft. Again Marchetti was assigned the task of developing a suitable system. In only a few days, Marchetti and his team converted the picket-ship radar into the AN/TPS-3, a lightweight, transportable system that could be assembled and placed into operation by a small crew in 30 minutes.〔Zahl, Lt. Col. Harold A., and Major John W. Marchetti; "Radar at 50 Centimeters," ''Electronics’’, Jan. 1946, pp. 98-104; http://www.infoage.org/html/elec-1946-01-p098-tps-3.html〕 Somewhat later, the set was modified as a mortar-locating radar, the AN/TPQ-3.〔Everts, J. T., and W. P. Goldberg; "Location of Mortars by Radar," ''Coast Artillery Journal'', Feb.-Mar., 1948, pp. 20-24〕 During the war, about 900 of these early-warning and mortar-locating systems were built, including 24 sets used in the D-Day Normandy landing. For the continuing war years, Marchetti was engaged in a wide variety of radar projects. One of the largest activity was his support to the Rad Lab at MIT in developing a mobile, gun-laying, microwave system, eventually designated the SCR-584. Undoubtedly the best-known radar system of the war, this included the M-9 analog computer that set the stage for great post-war advances in this field.〔Colton, Roger B.; "Radar in the United States Army," ''Proc. IRE'', vol. 33 (1947), pp. 740-753〕 Attacks on England by German V-1 flying bombs began in early 1944. Several SCR-268 systems upgraded to 600 MHz were rushed to England and set up on the coast to direct the anti-aircraft guns. When first used, the radar-directed guns actually were reduced in their hits. Marchetti was sent to England to check the radars. He found the electronic function was correct; however, the signal being sent to the gun-aiming analog computer was not the direct reflection from the V-1 but a signal being reflected from the nearby English Channel. After a minor change in the equipment as well as in the operating procedure, the hit probability increased from a few percent to around 90 percent, subsequently saving thousands of lives. For his efforts, Marchetti was awarded the Order of the British Empire(OBE).〔''Opt. Cet.'', Marchetti, "Oral History"〕 After correcting the SCR-268 operation, Marchetti remained in England, and in June 1944, he participated in the D-day liberation of Europe. Following the Omaha Beach landing in Normandy, he served as the radar officer for the First Army and was promoted to Major. Among other duties, he searched in unsecured areas for German radar installations. After several months of service in Europe, he returned to Fort Monmouth. In 1999, the Federation of French War Veterans awarded Marchetti the Normandy Medal in recognition of his contributions. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「John W. Marchetti」の詳細全文を読む スポンサード リンク
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