Classification--It is a nine pins tube.oxide coated cathode of indirect heated.
Application--It intended for use a NF voltage amplifier or Phase inuerter. It is Low noise tube.
Dimensions--Dimensions, outline diagrams of the tube and bases and the arrangement of electrode commections to the base terminals are shown in Figures 1 and 2 .

Nominal operating conditions and parameters

Heater voltage……………………………………………………………12.6 V*
Heater current……………………………………………………..........0.15 A
Plate voltage………………………………………………………………250 V
Grid voltage……………………………………………………………….－2 V
Plate resistance…………………………………………………………62.5 kohms
Plate current………………………………………………………………1.2 mA
Amplification factor…………………………………………………………100

Characteristics-Average characteristics

Figure 3. shown typical curves of plate currents as a function of grid voltage for several values of plate voltages.

Fig.3

Limiting Operation Conditions for Safe Nor-nor simultaneous ratings

Maximum plate voltage……………………………………………… 330 V
Maximum Grid voltage………………………………………………-- 50 V
Maximum Grid voltage………………………………………………....0 V
Maximum Power of plate……………………………………………1.2 W