directly-heated cathode

Definition

Electronics

  • A cathode, within a thermionic tube, which is directly connected to a source of current. Such a cathode, usually in the form of a filament, becomes heated as current passes through it, and emits electrons when sufficiently heated. Also called filament (2), filament cathode, filamentary cathode, or filament-type cathode.
http://www.dictionarycentral.com/definition/directly-heated-cathode.html