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CV1285 / NR73 double triode

Size This valve measures 102x45mm overall and has an octal base.


This is the equivalent of the ECC31. See also CV181 which is listed as a modified NR73.

Heater voltage 6.3V
Heater current 950mA
Max anode voltage 300V
Anode current * 6mA
Mutual conductance * 2.3mA/V
Amplification factor * 32
Anode impedance * 14k ohms
Max anode dissipation 5W
Max cathode current 50mA
Ca-all 1.0pF
Triode 1  
Cag 3.4pF
Cgc 4.0pF
Cac 1.9pF
Triode 2  
Cag 3.75pF
Cgc 4.0pF
Cac 1.0pF

*: At Va=250, Vg=-4.6.

Pin Function
1 n/c
2 Heater
3 Anode 1
4 Grid 1
5 Grid 2
6 Anode 2
7 Heater
8 Cathode