Timeline Filter by: Decade or Famous Calls The Network The Business
De Forest Audion triode invented
De Forest Audion triode invented
1906
First multiplexed telephone circuits
1910
Vacuum tube repeater demonstrated
Lee de Forest
1913
Hartley invents the Hartley oscillator
Ralph Hartley
1915
Arnold perfects the vacuum-tube telephone amplifier
Harold D. Arnold
1915
Otto Zobel invents m-derived filters
Otto Julius Zobel
1920
Type C carrier system deployed
1922
Davisson–Germer experiment confirms wave particle duality of matter
Clinton Davisson Lester Germer
1927
Black invents the negative feedback amplifier
Harold Stephen Black
1927
Hartley formulates Hartley's law
Ralph Hartley
1928
Nyquist and Johnson explain thermal noise in conductors
John Bertrand Johnson Harry Nyquist
1928
Anti-sidetone circuit developed
Anti-sidetone circuit developed
1930
Bell Labs scientists pioneer crystal lattice (quartz) filters
Lloyd Espenschied Warren P. Mason Otto Julius Zobel
1934
Speech synthesizing system demoed at Bell Labs
Homer Dudley Harvey Fletcher
1936
Mead, Carson and Schelkunoff publish their 'Hyper frequency wave guides' paper
John Renshaw Carson Sallie Pero Mead Sergei Alexander Schelkunoff
1936
First Nobel awarded for work done at Bell Labs (electron diffraction)
First Nobel awarded for work done at Bell Labs (electron diffraction)
1937
Crossbar switching introduced
Crossbar switching introduced
1938
p-n junction (transistor/solar precursor) invented at Bell Labs
Russell Ohl
1939
A Modern Aladdin's Lamp, About Vacuum Tubes (Western Electric)
A Modern Aladdin's Lamp, About Vacuum Tubes (Western Electric)
1940
Transistor invented at Bell Labs
Transistor invented at Bell Labs
1947
Bottle of Magic (The Vacuum Tube)
Bottle of Magic (The Vacuum Tube)
1948
Pfann invents zone refining (melting), enabling purer silicon for transistors and semiconductors
Pfann invents zone refining (melting), enabling purer silicon for transistors and semiconductors
1952
The Transistor (Bell System)
The Transistor (Bell System)
1953
Transistors first used in telephone equipment
1953
The Bell Solar Battery
The Bell Solar Battery
1956
Bell Labs scientists win Nobel Prize for the transistor
John Bardeen Walter Brattain William Shockley
1956
Improved echo suppressors deployed
1957
Kahng and Atalla invent the MOSFET
Mohamed M. Atalla Dawon Kahng
1959
West and Sessler invent the foil electret microphone
James West
1962
Genesis of the Transistor (Bell Labs)
Genesis of the Transistor (Bell Labs)
1965
World's first electronic telephone switch (No. 1 ESS) installed
World's first electronic telephone switch (No. 1 ESS) installed
1965
Lucky invents the adaptive equalizer
Robert W. Lucky
1965
Boyle and Smith invent the charge-coupled device
Willard Boyle George E. Smith
1969
Inventing the Negative Feedback Amplifier (AT&T)
Inventing the Negative Feedback Amplifier (AT&T)
1980
Inventing the Laser (Bell Labs)
Inventing the Laser (Bell Labs)
1988