Fessenden, Reginald Aubrey

SUBJECT AREA: Broadcasting, Electronics and information technology, Telecommunications

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b. 6 October 1866 East Bolton, Quebec, Canada

d. 22 July 1932 Bermuda

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Canadian radio pioneer who made the first known broadcast of speech and music.

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After initial education at Trinity College School, Port Hope, Ontario, Fessenden studied at Bishops University, Lennoxville, Quebec. When he graduated in 1885, he became Principal of the Whitney Institute in Bermuda, but he left the following year to go to New York in pursuit of his scientific interests. There he met Edison and eventually became Chief Chemist at the latter's Laboratory in Orange, New Jersey. In 1890 he moved to the Westinghouse Electric and Manufacturing Company, and two years later he returned to an academic career as Professor of Electrical Engineering, initially at Purdue University, Lafayette, Indiana, and then at the Western University of Pennsylvania, where he worked on wireless communication. From 1900 to 1902 he carried out experiments in wireless telegraphy at the US Weather Bureau, filing several patents relating to wire and liquid thermal detectors, or barretters. Following this he set up the National Electric Signalling Company; under his direction, Alexanderson and other engineers at the General Electric Company developed a high-frequency alternator that enabled him to build the first radiotelephony transmitter at Brant Rock, Massachusetts. This made its initial broadcast of speech and music on 24 December 1906, received by ship's wireless operators several hundred miles away. Soon after this the transmitter was successfully used for two-way wireless telegraphy communication with Scotland. Following this landmark event, Fessenden produced numerous inventions, including a radio compass, an acoustic depth-finder and several submarine signalling devices, a turboelectric drive for battleships and, notably, in 1912 the heterodyne principle used in radio receivers to convert signals to a lower (intermediate) frequency.

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Principal Honours and Distinctions

Institute of Electrical and Electronics Engineers Medal of Honour 1921.

Bibliography

US patents relating to barretters include nos. 706,740, 706,742 and 706,744 (wire, 1902) and 731,029 (liquid, 1903). His invention of the heterodyne was filed as US patent no. 1,050,441 (1913).

Further Reading

Helen M.Fessenden, 1940, Fessenden. Builder of Tomorrow. E.Hawkes, 1927, Pioneers of Wireless, London: Methuen. O.E.Dunlop, 1944, Radio's 100 Men of Science.

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