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Edwin Howard Armstrong

American inventor of FM radio and the superheterodyne receiver.

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The developer of frequency modulation broadcasting and the superheterodyne receiver, Edwin Howard Armstrong, was an American inventor and radio-frequency engineer.[1] A total of 42 patents were held by Armstrong, and his accolades included the French Legion of Honor and the Institute of Radio Engineers' first Medal of Honor.[2]

Key facts and history

At age eight he contracted Sydenham's chorea, a neurological disorder, which caused a physical tic and led to home tutoring for two years.[3] He enrolled at Columbia University in 1909 and graduated with an electrical engineering degree in 1913.[4][2] While an undergraduate, Armstrong began work on his first major invention, the regenerative circuit, using positive feedback to achieve amplification hundreds of times greater than before.[5][6] In 1933 he was granted five US patents covering wide-band FM, a system that varied carrier frequency over a wide band to reduce noise.[7][8]

Armstrong came into the world on December 18, 1890, as the oldest of three children in the Chelsea neighborhood of New York City.[9]

What the cited sources add

The same source states that the Institute of Radio Engineers refused to rescind a gold medal awarded to Armstrong for the feedback circuit even after de Forest won the patent battle.[8] The account from America's Apex Broadcasting Stations describes that FM was the third and most elegant solution to improve radio broadcasting.[10]

References

  1. Wikipedia, "Edwin Howard Armstrong" (CC BY-SA 4.0), which cites: Lawrence P. Lessing, "Edwin H. Armstrong", Britannica; "Armstrong, FM Inventor, Dies In Leap From East Side Suite", The New York Times, February 2, 1954, p. 1 (original not read by us) en.wikipedia.org
  2. Wikipedia, "Edwin Howard Armstrong" (CC BY-SA 4.0), which cites: "Who Was Who in American History – the Military", Marquis Who's Who, 1975, p. 15 (we also read that source) en.wikipedia.org
  3. Wikipedia, "Edwin Howard Armstrong" (CC BY-SA 4.0), which cites: Lessing 1956, p. 26 (original not read by us) en.wikipedia.org
  4. Wikipedia, "Edwin Howard Armstrong" (CC BY-SA 4.0), which cites: "What Everyone Should Know About Radio History: Part II" by Prof. J. H. Morecroft, Radio Broadcast, August 1922, pp. 294–302. (original not read by us) en.wikipedia.org
  5. Wikipedia, "Edwin Howard Armstrong" (CC BY-SA 4.0), which cites: DeForest Radio Co. v. General Electric Co., 283 U.S. 664 (May 25, 1931). Fleming and Lilenfeld had advocated high vacuum. "Of critical importance in the present (we also read that source) en.wikipedia.org
  6. Wikipedia, "Edwin Howard Armstrong" (CC BY-SA 4.0), which cites: "Operating Features of the Audion" by E. H. Armstrong, Electrical World, December 12, 1914, pages 1149-1152. (original not read by us) en.wikipedia.org
  7. Wikipedia, "Edwin Howard Armstrong" (CC BY-SA 4.0), which cites: Raymond, "Air War: Legal Battles Over FM Radio", Fathom; Frost (2010), page 95. (original not read by us) en.wikipedia.org
  8. "Edwin Armstrong", wirelesshistoryfoundation.org, April 25, 1999. facts only, no text reused. wirelesshistoryfoundation.org
  9. Wikipedia, "Edwin Howard Armstrong" (CC BY-SA 4.0), which cites: Tsividis, Yannis, "Edwin Armstrong: Pioneer of the Airwaves", Columbia Magazine, Spring 2002; "Armstrong, FM Inventor, Dies In Leap From East Side Suite", The New York Times, February 2, 1954, p. 1 (original not read by us) en.wikipedia.org
  10. America's Apex Broadcasting Stations of the 1930s by John Schneider.. facts only, no text reused. theradiohistorian.org

Each numbered sentence above was checked against the source it cites before publication. Sentences citing Wikipedia adapt text from the English Wikipedia article Edwin Howard Armstrong (contributors), used under CC BY-SA 4.0; this entry is available under the same licence. Other sources were used for facts only; no text or images are copied from them.

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Sources

Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.

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