Overview

thermionic valve


Related Overviews

transistor

Sir Joseph John Thomson (1856—1940) physicist

diode

radio

 

'thermionic valve' can also refer to...

 

More Like This

Show all results sharing this subject:

  • Physics

GO

Show Summary Details

Quick Reference

An electronic valve based on thermionic emission. In such valves the cathode is either directly heated by passing a current through it or indirectly heated by placing it close to a heated filament. Directly heated cathodes are usually made of tungsten wire, whereas indirectly heated cathodes are usually coated with barium and strontium oxides. Most electronic valves are thermionic vacuum devices, although a few have cold cathodes and some are gas-filled (see thyratron). See diode; triode; tetrode; pentode.

Subjects: Physics.


Reference entries

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.