travelling-wave tube

== English == === Alternative forms === traveling-wave tube, traveling wave tube, travelling wave tube === Noun === travelling-wave tube (plural travelling-wave tubes) (electronics) A type of vacuum tube which amplifies electromagnetic signals, where the electron gun fires down the tube with an unmodulated electron beam, that passes through an interaction array, where the EM-signal is fed, which interacts with the electron beam, bunching the electrons, and transferring power to the signal. ==== Usage notes ==== The TWT's electron gun is typically a thermionic cathodic emitters. The usual design for the interaction grid is a helix wrapped around the beam's transmission tube. Modern TWTs have a depressed collector to recuperate unused power in the electron beam after it has passed through the interaction grid. Modern tubes are metal- instead of glass-encased. Radiator fins may be attached for heat management. ==== Synonyms ==== TWT (abbreviation) ==== Hypernyms ==== vacuum tube ==== Derived terms ==== TWT (abbreviation) cold cathode travelling-wave tube (cold cathode TWT) ==== Translations ==== === References === === Further reading === traveling-wave tube on Wikipedia.Wikipedia