Fessenden, Reginald Aubrey

Born Oct. 6, 1866, in East Bolton, Quebec, Canada; died July 22, 1932, in Hamilton, Bermuda. American scientist; specialist in electrical engineering and radio engineering.

Fessenden did not have a specialized education. He began studying electromagnetic waves in 1895, and in 1899 he demonstrated the usefulness of the wireless telegraph for weather reporting. In 1900 he developed industrial models of high-frequency (60/kilohertz) induction generators. In 1901, together with the American scientist E. F. W. Alexanderson, Fessenden built a high-frequency arc generator and succeeded in transmitting the human voice by radio. He invented an electrolytic detector in 1902 and proposed a method for heterodyne reception in 1905.

Fessenden was awarded more than 300 patents, mainly for his inventions in radio engineering. Many of them pertain to marine navigation and signaling, such as the sonic depth finder, various direction finders, and electroacoustic devices.