The Edison
laboratory had done little work radio waves since the 1880s,
. The lab designed improved diodes and GE
manufactured these vacuum tubes during the war for wireless
telegraphy. special research branch Western
Electric's Engineering Department was established examine
the possibility electronic amplifier for long distance
telephone circuits. This became the basis of
their involvement radio and their dominance long distance
telephony. 1919 and AT&T pooled their patents and formed
the Radio Company America hold them. The first commercial radio station began transmission in
late 1919. Both companies
prepared themselves manufacture radio equipment the
1920s.XIII-14
The Bell system could not ignore this threat and
redoubled the efforts their industrial laboratories into
electronic technology. When Forest and other experimenters
found that the triode could act amplifier AT&T acted
quickly acquire the audion patents.2® The first radios
were primitive crystal sets, but these were soon replaced by
radios with several vacuum tubes and loud speakers. 25
The basic elements radio had been assembled the
time the World War: oscillators generate waves,
electronic detectors pick them up, and the triode amplify
them.2^ GE's involvement incandescent light bulbs had
brought its research organization into the field of
electronics. 1921 there were over 250,000 sets the and
sales increased 400,000 sets 1922
