Don't know if this would help

General characteristics (by UH=6.3V, UA=250V, RK=600
Ohm):
Type 6N1P 6N1PVI 6N1PEV
Filament (heater) current, mA 600± 50 600± 50 600± 50
Anode current, mA 5,6 - 10,5 7,5± 1,5 7,5± 1,5
Reverse grid current, mkA £1 £0,5 £0,2
Dissipate cathode-heater current, mkA £15 £15 £12
Mutual conductance, mA/V 4,5± 1,0 4,45± 0,65 4,5± 0,8
Gain coefficient 35± 7 35± 7 35± 7
Input resistance (by f=60 MHz), Kohm
Equivalent noise resistance, Kohm
Vibration noise (by RA=2 KOhm), mV £100 £80 £50
Inter electrode capacitance, pF:
input 3,1±1,1 3,3±0,9 3,05±0,55
output 1st triode 1.6±0.5 1.75±0.5 1.75±0.5
output 2nd triode 1.7±0.5 1.95±0.5 1.75±0.5
transfer 1.85±2.2 £2.6 £2.6
Operation period, hrs ³3000 ³3000 ³5000
Limited operating values:
Type 6N1P 6N1PVI 6N1PEV
Filament voltage, V 5,7-7 5,7-7 6-6.6
Anode voltage, V 300 300 250