Armstrong is the most important engineer in the Electrical Engineer’s list, and one of greats of the 20th century. Most of the greats are known for one or two key innovations: Widlar and the op amp, Cray and vector supercomputers, Sutherland for both Sketchpad and flight simulation. Armstrong had three : regeneration, superheterodyning, and frequency modulation. He was the last of the line of heroic individual American inventors, and he came to a particularly American end - death by lawyers. His last struggles also bear on questions that are puzzling to this day, such as why AM radio hasn't been swept away by FM.
Here he is in the late 1940s, looking like a particularly unsympathetic banker, but showing the fierce and uncompromising attitude that ultimately did him in.