Edwin H. Armstrong, an engineer and inventor
in the field of radio, lived in this house from 1902 to 1923.
Armstrong invented two of the electronic circuits that are the
basis of modern telecommunications. Armstrong also invented
the frequency modulation (FM) system of radio broadcasting.
While still a boy, Armstrong set about
becoming an inventor. His homemade radio equipment eventually
filled his bedroom, and during high school, he built a 125-foot
tall radio antenna on the lawn of his house. Armstrong made
his first important discovery while studying engineering at
Columbia University. During the summer of 1912, he created a
new regenerative circuit and tested this device in the turret
room of the Yonkers house. Armstrong received distant stations
loudly enough to be heard without earphones, not possible before
the creation of this circuit. Armstrong's regenerative circuit
was the first radio amplifier and it became the basis of the
continuous-wave transmitter that remains key to radio broadcasting.
Armstrong obtained his engineering degree
in 1913, and continued at Columbia serving as an instructor
and assistant to physicist and inventor Michael Pupin. Serving
in the U.S. Army Signal Corps during World War I, Armstrong
was asked to attempt detection of possible enemy shortwave transmissions.
To achieve this, he created an eight-tube receiver which greatly
amplified weak signals. Named the superheterodyne circuit, this
was another of Armstrong's inventions that became essential
to the operations of telecommunications devices. The sales of
rights to his inventions made Armstrong a millionaire in the
1920s. He continued teaching as a professor at Columbia, and
in 1923 married Marion MacInnes.
After a legal battle to control his patent
for the Regenerative Circuit that lasted from 1922 to 1934,
Armstrong eventually lost the case in the US Supreme Court,
but he continued to be recognized by the scientific community
as the inventor of this circuit. In an effort to eliminate static,
Armstrong designed a new system of radio broadcasting. In 1933
he demonstrated the wide-band frequency modulation (FM) system.
This new system was not immediately adopted by broadcasters
due to financial considerations; the new system required changes
to some of the basic equipment. After World War II, however,
FM broadcasting burgeoned. Unfortunately for Armstrong, he again
faced patent challenges. He undertook twenty-one lawsuits against
corporations that infringed on his frequency modulation system
patents. With another protracted legal battle looming and undergoing
the stress of personal illness as well as a separation from
his wife, Armstrong committed suicide on January 31, 1954. It
was not until 1967 that the lawsuits were finally settled by
Armstrong's widow; all of the suits were decided in Armstrong's
Armstrong was posthumously
elected by the International Telecommunications Union in Geneva
to its roster of electrical pioneers, joining such figures as
Alexander Graham Bell, Marconi, and Michael Pupin. Armstrong had
also received the Franklin Medal in 1941, the most prestigious
award in American science.
The house in Yonkers remained in the
Armstrong family until 1957. When it was designated as a National
Historic Landmark on January 7, 1976, it was still well-maintained.
Beginning in 1979, however, the property appeared to be endangered
by proposed residential development. The house was not maintained
during this period, in anticipation of sale of the property
for development. The structure deteriorated and suffered fire
damage, which destroyed part of the roof and caused severe damage
to the interior walls. The Edwin H. Armstrong House was demolished
in February 1983 and the site was leveled. The Landmark designation
was withdrawn on March 5, 1986 and the property was also removed
from the National Register of Historic Places.