New Developments in Oxide-coated Cathodes

The first of these articles deals with oxide-coated cathodes designed to be loaded with current densities several times higher than ordinary oxide-coated cathodes can withstand, and which yet have a life of a few thousand hours. Although these new cathodes cannot rival the L type of dispenser cathode as regards their permissible current density, they are cheaper and have a lower operating temperature, which removes the problem of insulation between heater and cathode. Where cathode-ray tubes arc used in fully transistorized, battery-fed equipment, such as television receivers, television cameras, oscilloscopes, etc., low power consumption by the heater is an important consideration. The second article concerns an oxide-coated cathode developed for applications of this kind, whose heater consumes only 0.5 W.