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STC CV398 / 4B/603E pulse modulator tetrode

Size This valve measures 152x60mm overall and has a 4 pin base.


Heater voltage 26V
Heater current 2A
Max anode voltage 12kV
Max negative grid voltage -1kV
Max peak positive grid voltage 300V
Max screen grid voltage 1.25kV
Max screen grid voltage, Ia=0 1.35kV
Max anode dissipation 60W
Max screen grid dissipation 8W
Max peak anode current 15A
Cag max 2pF
Cgc 37pF
Cac 7.5pF


Pin Function
1 Heater
2 Screen grid
3 Control grid
4 Heater and cathode
TC Anode
Top quarter view Bottom quarter view