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CV257 triode

This valve measures 125x60mm overall

This is a disc seal triode intended for pulse operation. It's serial number is 2504. In pulse mode a pair of CV257 valves could produce 10kW RF at 600MHz.

Heater voltage6.3V
Heater current4A
Max DC anode voltage600V
Max pulse anode voltage4kV
Max anode dissipation *75W
Min peak emission15A
Amplification factor **22
Mutual conductance **20mA/V
Efficiency at 500MHz with 11db gain60%
Efficiency at 1GHz with 8db gain40%

*: At ambient temperatures of 30°C forced air cooling of greater than 5 cubic feet per minute with a pressure drop equivalent to 2" of water is required.
**: At Va=500V, Ia=100mA

Quarter view
In the image above, the heater connection is leftmost, with the heater/cathode connection being the first disc. The grid is the next disc and the anode the far end. The anode connector has an internal radiator (see below).
Quarter view

This file was last modified15:23:22, Tuesday September 02, 2014