Rare output beam tetrode 30P1M (later name 30P1S) with a the heated oxide cathode is intended for an energy amplification in devices of broad application. Made in USSR, MELZ factory (from 1949 till 1950 only). NOS and never used before!

Filament voltage: 30V;

Anode voltage: 110V;

Voltage of the second grid: 110V;

Bias voltage on the first grid: -7.5V;

Filament current: 300 ± 25mA;

Anode current: 70 ± 22mА;

Second mesh current: < 12mA;

Steepness: 10±2.5 mA/V