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CV78 grounded-anode triode

Size This valve measures 67x35mm overall and has a B9G base

This valve is of a similar internal construction to the CV172 noise diode.

Heater voltage 6.3V
Heater current 0.6A
Max anode voltage 250V
Max anode dissipation with grid leak <1k ohm 8W
Max anode dissipation with grid leak > 1k ohm 4W
Mutual conductance At Va=250V, Ia=32mA 15mA/V
Amplification factor 50
Anode impedance 3100 ohms
Efficiencies as as oscillator
50cms 4%
60cms 12%
70cms 18%
80cms 32%
90cms 27%
100cms 30%
Cag Measured with spigot connected to anode 7.4pF
Ca (c+h) 6pF
Cg (c+h) 5.7pF


Pin Function
1 Heater
2 Anode
3 Anode
4 Grid
5 Grid
6 Anode
7 Anode
8 Cathode
9 Heater

Inside view Inside view