Triode He said Radio jamming Commentary

Lee de Forest, Irving Langmuir electromagnetism

Triode

• Audion
• Lee de Forest took a Fleming valve
• added a grid electrode between filament and plate.
• He left a rarified gas in the tube,
• believing it was necessary for electrical conduction,
• and wired it so a small current flowing to the grid
• controls a larger current flowing from the filament to the plate.
• Kenotron
• Irving Langmuir built a Fleming diode with a complete vacuum
• and found it could rectify higher voltages.
• Pliotron
• Irving Langmuir built an Audion with a complete vacuum
• and found it could amplify higher frequencies.

He said

• De Forest said he didn’t copy Fleming.
• He said he didn’t know how the Audion worked.
• He said a low-pressure gas was needed,
• but the gas made the Audion unpredictable.
• He said his “spade detector” didn’t infringe
• on Fessenden’s electrolytic detector.
• He said his “sparkless” arc transmitter didn’t infringe
• on Valdemar Poulsen’s arc transmitter.
• He said he created his “ultra-audion” circuit
• before Edwin Howard Armstrong’s regeneration circuit.
• In his 1950 autobiography, de Forest said
• that he was the father of radio.

Radio jamming

• For the 1901 International Yacht races,
• de Forest and two other companies—Marconi and
• the American Wireless Telephone and Telegraph
• Company—jammed each others’ transmissions
• because no one at the time had effective tuning.
• For the 1902 races, the International Wireless Company
• set up a transmitter to deliberately jam the other two.