General Science

  • noun an electronic relay made up of a gas-filled tube in which a signal applied to the control grid initiates, but then cannot control, a transient anode current


  • A hot cathode gas-filled tube which incorporates one or more control electrodes. The control electrodes assist in the initiation of current flow, and usually do not otherwise affect the operation of the tube. Used, for instance, as a switching device for modulators.