Born in 1890, inventor Edwin Howard Armstrong was impressed by
the work of Guglielmo Marconi and Lee deForest and took their innovations
to a new stage.
Early in the 20th century, Lee deForest had invented a three-element
electron tube. Armstrong redesigned that tube to feed electrons
from the transmission back through the tube. This regenerative
circuit allowed radio engineers to broadcast a more powerful
During World War I, Armstrong served in the signal corps and invented
a small, lightweight radio for airplane pilots. During that time,
Armstrong also developed the superheterodyne circuit, which changed,
amplified and transformed radio waves into sound vibrations. The
superheterodyne became an integral part of commercial radios, allowing
listeners to tune into a single station with optimum reception.
Purchasing Armstrongs regeneration and superheterodyne patents,
Westinghouse was able to start up the nations first regular
radio station, KDKA/Pittsburgh. In the 1930s, Armstrongs efforts
to create staticless radio led to the invention of wide-band
frequency modulation and the development of FM radio.
Edwin Armstrong died on January 31, 1954.
Edwin Armstrong was inducted into the Radio Hall of Fame in 1990.
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