Reginald Aubrey Fessenden

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Reginald Aubrey Fessenden


Canadian Electrical Engineer and Inventor

A disciple of Thomas Edison (1847-1931), Fessenden made major contributions to wireless telephony and radio. In 1906 he made the first broadcast of voice and music from Brant Rock, Massachusetts. The principle of using electromagnetic waves to send detailed information over great distances to one or more receivers was central to many of the most significant technologies of the twentieth century.

"Reg" Fessenden was born in East Bolton, Quebec, where his father was a minister. Although the family moved to Niagara Falls, Ontario, Fessenden returned to Quebec, where he completed his bachelor's degree at Bishop's College while teaching high school mathematics. Fessenden changed jobs frequently during his life, alternating between academics and industry. He was a school principal in Bermuda, from 1884-86, where he met his future wife, Helen, but he returned to New York to work for Edison, from 1887-90, before moving on to further industrial positions. Fessenden then returned to teaching, as professor of electrical engineering at Purdue University (1892), and then at the University of Pittsburgh (1893-1900). In 1900, Fessenden began working for the U.S. Weather Bureau, on the new technology of wireless telegraphy, but two years later he left to form his own business, the National Electric Signaling Company.

Fessenden's inventions in the first decade of the twentieth century were originally intended to improve the transmission of telegraph signals, but they were also crucial for making a successful wireless telephone. His "electrolytic detector" received radio waves much more clearly than the crude "coherer" used by other systems. His high-frequency alternator, developed in conjunction with the Swedish engineer E. Alexanderson (1878-1975), produced smooth, continuous radio waves capable of carrying a clear sound signal, unlike the noisy, intermittent bursts generated by existing spark gap technology. Fessenden also developed the key ideas of "amplitude modulation" (AM) and the "heterodyne principle," which explained how to mix sound with radio waves for transmission, and how to decode them at the receiving end. Many wireless telegraph stations used Fessenden equipment, and thus received his first radio broadcasts of December 24 and 31, 1906, hearing voices and music through headsets that had previously only produced dots and dashes.

Fessenden soon succeeded in producing wireless telephone communication over thousands of miles. Unfortunately, relations between Fessenden and his financial backers broke down, and the company collapsed in 1911. It took Fessenden until 1928 to resolve ownership of his wireless patents, after lengthy and expensive court battles. In the meantime, he consulted for the British and American governments during World War I, developing signaling systems for submarines, antennas used to detect incoming zeppelins, and a superior depth-measuring instrument for ships. During the 1920s, when commercial radio began, Fessenden received greater recognition for his work, and won several honors. He was increasingly in poor health, however, worn out from his legal disputes, and he gradually withdrew from public life. Fessenden retired to Bermuda in 1928, to devote himself to his new interest, research on ancient civilizations. He was happier in Bermuda than in the U.S., but died just four years later at 65.

Reginald Fessenden was a talented, original, and multi-faceted inventor. Although he had many interests, his contributions to radio and wireless communication were by far the most important. Virtually every aspect of twentieth-century life was affected by technologies that his work made possible, such as radio and television broadcasting, wireless point-to-point communications, satellites, and personal mobile phones. Fessenden was also highly idealistic, and always stuck to his personal beliefs, even at his own cost. This meant that he was not as successful in business as his contemporary, Guglielmo Marconi (1874-1937), but he did manage to attract a few loyal friends and followers.