Russian audiophile 4P1L tube

Perfect tube with heater voltage / current

2,1 / 4,2 V / 0,65/0,325 A.

With direct heating & lowest anode voltage.

The pentode is fine up to 100 Mc/s.

Eqivalent to the 4L1S / 4LS1. Copy of RL2 / 4P6 Wermacht tubes.

Penthode on direct heating.

The tubes are never used.

SVETLANA =C= PLANT.

Military tubes.