You may not consider him a traditional Columbia entrepreneur but Edwin Armstrong ’13SEAS has been called “the most prolific and influential inventor in radio history”. He is credited with inventing three circuits that are fundamental to the radio, the television, and to radar systems. As an undergraduate, Mr. Armstrong created what he called the “regenerative” circuit which changed how the radio would operate for ever.
Yonkers History.org reported that after graduation from Columbia in 1913, Armstrong worked as an instructor at Columbia. When the US entered the war in 1917, he joined the Army Signal Corps and rose to the rank of Major—his preferred title for the rest of his life. While in the service, he invented the super–heterodyne circuit which amplified even further the sound of radio transmission. This invention brought him into contact with David Sarnoff, who became President of Radio Corporation of America and whose bright and attractive secretary, Marion Maclnnis, Armstrong later married.
According to his Wikipedia page Armstrong was born in New York City, New York, in 1890. He studied at Columbia University where he was a member of the Epsilon Chapter of the Theta Xi Fraternity. He later became a professor at Columbia University. He held 42 patents and received numerous awards, including the first Institute of Radio Engineers now IEEE Medal of Honor, the French Legion of Honor, the 1941 Franklin Medal and the 1942 Edison Medal. He is a member of the National Inventors Hall of Fame and the International Telecommunications Union’s roster of great inventors.