T. A. Edison
Accidental discovery of emission and rectifier effects (vacuum tube)
J.J. Thompson
Discovery of the corpuscle (electron). The name
electron had been suggested in 1891 by Professor Stony for his
conjectured electric particles in a chemical context.
ελεκτρον
(electron) - is Greek for amber and is the root from
which 'electricity' is derived.
P. Lennard
Use of an electrostatically operating auxiliary electrode with cathode-ray experiments
O. W. Richardson
Electron emission theory explains Edison effect
C. Hewitt
Relay effect by magnetic arc control (controlling an ionic discharge)
P. Lennard
Use of wire-mesh grids to electrostatically control electron velocity
A. Wehnelt
Discovery of the excellent emission qualities of alkaline earths (oxide cathode)
J. A. Flemming
Using the electron tube as a high-frequency detector
R. v. Lieben
Vacuum amplifier tube with magnetically controlled electron flow
L. de Forest
Detector tube with plate control
L. de Forest
Audion patent (single-grid tube)
J. A. Flemming
Tungsten filament for electron tubes
R. v. Lieben
Control grid (amplifier with mercury vapor filled tube)
J. Langmuir
Improving emission by thoriated-tungsten filament
O. v. Bronk
Radio-frequency amplifier
AEG
Mass production of Lieben tubes
L. de Forest
Regeneration - positive feedback
G. Leithäuser
Supressor-grid arrangement for cathode-ray experiments
J. Langmuir
Space-charge grid circuit
A. Meißner
Oscillator by positive feedback
J. Langmuir
Significance of high vacuum for the space charge
W. Schottky
Increasing transconductance by dual control
Schenkel
Indirectly heated cathode
W. Schottky
Protective grid
A. W. Hull
Screen grid
First public broadcast in U.K. from the Marconi works in Chelmsford
2MT Marconi transmitter at Writtle, Essex, began first regular public entertainment program.
BBC type approval marks (stamp regulations) introduced on all British sets and valves.
London (2LO), first British broadcasting station, commenced.
First programmes broadcast from the London, Birmingham, and Manchester stations.
Marconi-Osram Dull Emitter valves introduced - see DE4 .
British Broadcasting Company, Ltd., registered.
First outside broadcast, " The Magic Flute " (Mozart), from Covent Garden.
Cardiff station opened.
First broadcast play.
First charity appeal by wireless.
Glasgow station opened.
First broadcast from Savoy Hill.
Sir E. Rutherford's address to the British Association at Liverpool simultaneously broadcast from all B.B.C. stations.
Valve royalties abolished. Type approval and 'sealed sets' ended.
Aberdeen station opened.
Bournemouth station opened.
Newcastle station opened.
Mullard half owned by N. V. Philips Gloeilampenfabrieken of Eindhoven, Holland.
First broadcast from St. Martin-in-the-Fields, conducted by the Rev. Dick Sheppard.
First broadcast by King George V and King Edward VIII (then Prince of Wales) at opening of Wembley Exhibition.
Hull relay station opened.
BBC marks changed.
BBC mark no longer compulsory for BBC companies.
George Uhlenbeck and Samuel Goudschmidt
Discovery of electron spin
Mullard intoduce the PM series of azide process valves. - see PM3.
First transmission from Chelmsford, 5XX, B.B.C. high-power experimental station.
Daventry 5XX officially opened.
The British Radio
Valve Association (BVA) formed from the Valve Association.
Companies involved included A.C. Cossor, Edison Swan,
GEC, Marconiphone, Mullard and Standard.
Jobst/Telegen
Suppressor grid (pentode)
Rugby telegraph station opened.
N. V. Philips Gloeilampenfabrieken become sole owners of Mullard.
Tetrode introduced ?PM12?
Use of BBC marks had died out.
Pentodes and 5 pin base introduced
A.E.I. formed from Edison Swan (Edswan), BTH (Mazda) and Metrovick (Cosmos).
First BBC Regional station, Brookmans Park, opened.
First dual transmission from Brookmans Park.
B.B.C. commence television broadcasts.
K. Steimel
Hexode
First programme from Broadcasting House.
Empire Broadcasting from Daventry began.
K. Steimel
Triode-hexode
Droitwich station opened.
Burghead transmitting station opened.
Penmon (Anglesey) transmitting station opened.
Washford transmitting station opened.
Stagshaw transmitting station opened.