2 PCS GU-81M High Power Pentode Transmitting Generator Tube.Tesla Coil.Valve online Power Tube.Ryazan.Tested.

Vacuum tubes are in excellent condition, no dark rings from use. All the filaments of the lamps are intact, without damage, checked with a multimeter.

GU-81M
Generator pentode GU-81M with a directly heated tungsten carbide cathode in a glass shell and air cooling.
Designed to amplify power and generate high-frequency oscillations at frequencies up to 50 MHz with an output power of at least 700 W.
The GU-81M pentode is used in transmitters, high-power stages of low-frequency amplifiers and in other radio engineering devices of stationary equipment for general and special purposes.
Produced in glass version.
Cathode tungsten thoriated online carbide direct heating.
Socle special with 6 conclusions.
Working position vertical, a socle down.
Cooling air natural or forced.
Overall dimensions of the GU-81M pentode:
- lamp height - 260 mm;
- lamp diameter - 120 mm.
Weight not more than 1 kg.
Guaranteed shelf life of the GU-81M lamp is 12 years from the date of acceptance by the customer's representative.
Operating time not less than 1000 hours
Specifications: SSH3.310.018TU.