Reginald Aubrey Fessenden (October 6, 1866 – July 22, 1932) was a Canadian-born inventor, who did a majority of his work in the United States and also claimed U.S. citizenship through his American-born father. During his life he received hundreds of patents in various fields, most notably ones related to radio and sonar - wikipedia 
Fessenden is best known for his invention of the modulation of radio waves and the fathometer. Fessenden worked as a chemist for Thomas Edison during the 1880s and later for Westinghouse. Fessenden started his own company, where he invented the modulation of radio waves known as the "heterodyne principle," which allowed the reception and transmission on the same aerial without interference - thoughtco.com
Reginald Fessenden, the ''father'' of radio broadcasting in the US - wikimedia.org
Fessenden is best known for his pioneering work developing radio technology, including the foundations of amplitude modulation (AM) radio.
An aerial view of Cobb Island, Maryland.
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His achievements included the first transmission of speech by radio (1900), and the first two-way radiotelegraphic communication across the Atlantic Ocean (1906).
Penny postcard of Reginald Fessenden's Brant Rock, Massachusetts radio tower.
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In 1932 he reported that, in late 1906, he also made the first radio broadcast of entertainment and music, although a lack of verifiable details has led to some doubts about this claim - see First entertainment radio broadcast.
# See also * Early years * Early work * Radio work * Later years * Awards * Death and legacy * Quotations - First entertainment radio broadcast