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Comment on the mechanism of operation of the impregnated tungsten cathodeRecent life-test measurements, over 20,000-30,000 h, on impregnated tungsten cathodes in tubes employing an open-type electron-gun structure, show emission current degradation with time. This is in contrast to those recently published by Rittner on B-type cathodes, run in close-spaced diodes, taken some years ago. These more recent life-test results are consistent with the model suggested by Forman and disputed by Rittner that the barium coverage on an impregnated cathode is less than a monolayer for most of its life and decreases with time.
Document ID
19790058011
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Forman, R. (NASA Lewis Research Center Cleveland, Ohio, United States)
Date Acquired
August 9, 2013
Publication Date
March 1, 1979
Publication Information
Publication: Journal of Applied Physics
Volume: 50
Subject Category
ELECTRONICS AND ELECTRICAL ENGINEERING
Distribution Limits
Public
Copyright
Other