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which was needed to create a beam narrow enough to locate ships or planes. The antenna is mounted on a mast so it can rotate and also tilt to point up into the sky. The rotating mast extends through the roof to a large manual wheel in the room below which contains the radar equipment, so it can be
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being developed during the late 1930s on the roof of the US Naval
Research Laboratory, Anacostia, Washington DC. Operating at 200 MHz, it was the first rotating radar antenna. Research in radiolocation was started as early as 1922 by Naval radio engineers Albert Hoyt Taylor and Leo Clifford
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Closeup of the antenna of the first complete radar, installed "topside" of a building at the Naval
Research Laboratory, Anacostia, D. C. in the late 1930s. It is a "dirigible" antenna, meaning that it is so mounted that it can be turned to allow for around the compass
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Young. In 1930 at the newly opened NRL, with another engineer
Lawrence Hyland they began a research program. In 1934 they patented a radar system. This picture shows a "bedspring" antenna made of multiple
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magazine would have the copyright renewed in 1973. Online page scans of the
Catalog of Copyright Entries, published by the US Copyright Office can be found here.
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because it was published in the United States between 1929 and 1963, and although there may or may not have been a copyright notice, the
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The following pages on the
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Search of the
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for US works (depending on the date of the author's death), such as Canada (70 years
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magazine, Ziff-Davis
Publishing Co., New York, Vol. 34, No. 4, October 1945, p. 30
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Note that it may still be copyrighted in jurisdictions that do not apply the
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Experimental radar antenna, US Naval
Research Lab, Washington DC, 1930s
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Click on a date/time to view the file as it appeared at that time.
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Early radar antenna - US Naval
Research Laboratory Anacostia.jpg
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177:"Radar: The Silent Weapon of World War 2" in
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612:(101 KB)
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