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Oxide-Coated Cathodes

Author: E.E. Kimberly

It has been discovered that a cathode coated with an oxide of barium, calcium, or strontium will emit many times as well as uncoated metal. The temperatures of such coated cathodes need not be so high as those of uncoated cathodes, and a less expensive metal may be used. Lower plate voltages may also be* used. Uncoated cathodes are still used for tubes with very high voltage.

Last Update: 2010-10-05