1939
•  Television introduced at the New York World’s Fair.
•  RCA, GE, DuMont, Philco and two other companies sell the first television sets.
•  The first experimental FM stations go on air.

1938
•  Konrad Zuse invents the first binary computer.
•  Al Gross invents the walkie-talkie.

1937
•  Chester Carlson invents the xerographic copy method, but it will be 22 years before the first commercial Xerox Corp. photocopy machine introduced.
•  John Atanasoff begins work on the first electronic computer, completed in 1939.

1936
•  The Berlin Olympics televised.

1934
•  The Federal Communications Commission (FCC) established.

1933
•  Howard Armstrong patents FM radio.

1932
•  Guglielmo Marconi discovers microwaves.

1931
•  "Binaural," better known as stereo recording, invented separately by Alan Blumlein in England and A.C. Keller of Bell Labs.

1930
•  I.G. Farben AG develops magnetic plastic audio recording tape in Germany.