Virtual Valve Museum

Virtual Valve Museum

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STC CV2189 / V240C/2K Heil tube

Size This valve measures 65x17mm glass, and 30mm across the disk. It has a B7G base.


Heater voltage 6.3V
Heater current 0.26A
Tuning range 3950 to 4050MHz
Control grid voltage -40V
Resonator voltage 255 +/- 15V
Screen grid voltage
(adjusted to give a constant anode current of 35mA)
400V max
Anode voltage 300V max
Cathode current 65mA max
Screen grid dissipation 1.5W max
Power output 350mW min
Mean power input 18W max
Magnetic field 1200H

The total thermal drift from cold to the final operating frequency is between 7 and 10MHz and is completed in about 5 minutes. The frequency change with ambient temperature is about 50kHz per degree C.

Pin Function
1 Control grid
2 Cathode
3 Heater
4 Heater
5 Anode
6 Resonator
7 Screen grid


Top quarter view Bottom quarter view