Edwin H. Armstrong was born in Manhattan in 1890. His father was a publisher and his mother a former teacher. Both his parents encouraged his childhood interest in mechanics, although they were a little worried about the solitary habits and experimentation that would characterize his entire life. At age fourteen Armstrong read about Marconi`s transatlantic wireless message and decided to become an inventor himself. Determined to improve instruments for wireless transmission, he studied fiercely and eventually went to Columbia University`s School of Engineering.
While still a junior, he invented the regenerative circuit in 1912. This circuit amplified signals and thereby also became a generator of wireless waves. The invention led to a protracted patent suit with Lee DeForest, whose 3-element vacuum tube, the Audion, provided the basis for Armstrong`s work. Although the courts eventually decided in favor of De Forest, the scientific community recognized Armstrong as the inventor of the regenerative circuit.
During World War I Armstrong served as a signal officer in the United States military. He was sent to the front lines in France to monitor the American wireless communication system. While in France he invented the super-heterodyne circuit. This invention was a highly selective means of receiving and amplifying weak, high-frequency electromagnetic waves. Armstrong was awarded the French Chevalier de la Legion d`Honneur for his military service and became known in the electronics industry as Major Armstrong.
After World War I he returned to Columbia as a student and then a professor. David Sarnoff, the general manager of RCA, was impressed with the applications of the super-heterodyne circuit. Other members of the RCA board of directors were more skeptical until they witnessed Armstrong getting off an elevator carrying a radio in full operation with an opera program in progress. Armstrong sold the patent rights on his inventions and became a wealthy man during the 1920s radio boom.
Armstrong`s next project was the problem of static in radio. He solved this problem by varying the frequency, or the number per second, of radio waves instead of the amplitude, or power, of radio waves. Since natural static was a phenomenon of amplitude, varying a wide frequency range eliminated static as a problem. FM (for frequency modulation) transmission required basic changes in transmitters and receivers. Armstrong treated the promotion of FM as a crusade. He and his supporters took advantage of the dissatisfaction of the academic, literary, and artistic communities with the programming available on AM (for amplitude modulation) radio. Beginning in 1938 Armstrong addressed numerous clubs, organizations, and technological groups, promising a steady flow of high quality programs broadcast without technical difficulty. Progress was slow, and even Sarnoff, Armstrong`s supporter at RCA, had other priorities, namely television, which was given precedence over FM radio
Disagreement with Sarnoff, was not Armstrong`s only problem. Throughout the 1940s he continued to lose money on promoting FM radio, fighting protracted patent litigation, and attempting to ward off regulatory attempts. He desperately craved recognition, bringing lawsuits and writing letters to the editor in an effort to demonstrate his accomplishments.
Colleagues recognized his brilliance but viewed his desire for glory as obsessive and unnatural. Ill and despondent, in 1954 Armstrong put on his evening coat, hat, and gloves, and stepped out the window of his thirteenth-floor Manhattan apartment. Though his life did not end happily, his achievements are undeniable. He laid the foundation for modern radio and electronic circuitry. Radio, radar, and television broadcasting today still rely on Armstrong`s inventions.