thermionic
Electrons from heat
Thermionic describes the emission of electrons from a heated surface.
When metals or other materials reach high temperatures, electrons gain enough energy to escape into the surrounding space.
This principle underlies vacuum tubes and certain types of electron guns: thermionic emission, thermionic valve.
The technology dominated electronics before transistors.
Three-element electron tube
- diodeOne-way semiconductor
- pentodeFive-electrode vacuum tube
- tetrodeFour-electrode vacuum tube
- valveFluid flow controller
magnetron · nixie · oscillator · grid · plate · socket · getter · envelope
Negative subatomic particle
- cathodeElectrode current exits through
- filamentVery thin thread
- anodeOxidation electrode
- emitterThing that gives off
tungsten · barium · incandescence · glow · heater
Heat transfer through contact
- temperatureMeasured heat intensity
- heatTransferred thermal energy
- vacuumAbsence of matter
- ionizationCharge acquisition process
Increase in intensity
- rectificationAct of setting straight
- oscillationRepeated back-and-forth movement
- radioElectromagnetic wave receiver
- transmitterSignal-emitting device
receiver · audio · television · radar · computing · ENIAC · switching · microwave
triode
Three-element electron tube
valve · magnetron · nixie · oscillator · grid · plate · socket · getter · envelope
electron
Negative subatomic particle
conduction
Heat transfer through contact
- temperatureMeasured heat intensity
- heatTransferred thermal energy
- vacuumAbsence of matter
amplification
Increase in intensity
- rectificationAct of setting straight
- oscillationRepeated back-and-forth movement
- radioElectromagnetic wave receiver
transmitter · receiver · audio · television · radar · computing · ENIAC · switching · microwave
thermionicphotovoltaic
Light-to-electricity converting
photoelectric · cold cathode · secondary emission · piezoelectric
thermionicsolid-state
Using semiconductors, not tubes
semiconductor · transistorized · integrated circuit · digital · silicon-based