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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