Made in USSR 1987.12,one batch.All tubes 100% tested with military L1-3 tube tester,
The anode current and slope correspond to the factory settings 
(Ia value : minimal = 10mA, at an average = 15mA, to 20mA).
(S value : minimal = 10mA, at an average = 12,6mA, to 16mA)

Main technical characteristics 6N23P:

The heating voltage ...... 6.3 ± 0.6 V
Current of heating ... 310 ± 25 mA
The anode voltage is nominal (constant) ...... 100 V
Anode voltage limit (constant) ...... 300 V
The current of the anode of each triode 15+-5
Kathode limiting current ...... 20 mA
The cathode current is the limiting (pulse amplitude) ...... 200 mA
The grid voltage (constant) ...... 9 V
The grid voltage is the limiting (pulse amplitude) ...... 260 V
Power dissipated by the anode, limiting ...... 1.8 W
Power dissipated by the grid, limiting ...... 0.03 W
The voltage between the cathode and the heater is the limiting (constant) ...... -200 V
The steepness of the characteristics of each triode 8.... 12.7 mA / V
The gain of each triode is 34 ± 9
Input resistance at a frequency of 200 MHz ...... 500 Ohm
Equivalent resistance of intra-lamp noise ...... 300 Ohm
Resistance in the cathode circuit for automatic bias ...... 680 Ohm
Resistance in the grid limit chain ...... 1 Om
Input capacitance of each triode ...... 3.6 pF
Output capacitance of the first triode ...... 2.1 pF
Output capacitance of the second triode ...... 1.9 pF
The capacitance of each triode is 1.5 pF