Reinhardt, Nicholas Consultant, Lexington, Massachusetts.
Last reviewed:January 2020
- Principle of operation
- Related Primary Literature
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An electron device in which use is made of the electrostatically or magnetically controlled flow of electrons in an evacuated space, or of the phenomena accompanying the electron emission, acceleration, and collection associated with the flow. In common usage, completely evacuated tubes are called hard tubes; tubes containing a small amount of deliberately added gas or vapor are called soft tubes, but they are usually included in the family of vacuum tubes.
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