2 x GU-81M High Power Pentode Transmitting Generator Tube.Tesla Coil.USSR.Used.

Description

Generating lamp GU-81M
The GU-81M lamp is the most powerful generator pentode in a glass design with a directly heated tungsten thoriated carbide cathode with natural cooling.
It is designed to generate and amplify electrical oscillations of low and high frequencies and is widely used in radio communication and radio broadcasting, for ultra-high-quality reproduction of sound frequencies, in radio-electronic devices of experimental physics and medicine.
The lamp can be used in induction heating installations, including for hardening cutting tools and gears, high-quality drying and firing of ceramic parts, in the plastics and rubber industry for high-quality vulcanization, in the food industry for canning food, drying tea, vegetables, fruits, for drying grain.
The advantages of a lamp include:
high utilization of the anode voltage, that is, high efficiency;
high stability of parameters and performance in a wide range of changes in ambient temperatures - from minus 60 ° C to plus 350 ° C;
stability and performance when exposed to ionizing radiation;
instant readiness for work - no more than 5 seconds;
a sufficiently high mechanical strength of the structure, which allows the use of lamps not only in stationary, but also in mobile equipment;
a wide range of operating frequencies and a sufficiently high level of output power allows the lamp to be used in equipment for a wide variety of purposes.
Basic electrical parameters:
Parameter name, units
Norm
No less
No more
Heating voltage, V
11.8
13.4
Anode voltage, kV
3
Filament current, A
10.5
Anode current, mA
twenty
Reverse current of the first grid, μA
fifty
Leakage current between electrodes, μA
twenty
Displacement voltage of the first grid, V
- 115
-160
Output power, W:
at l = 25m
at l = 6m
750
400
Slope of characteristic, mA / V
4.5
6.5
The gain of the first grid relative to the second,%
2.6
3.7
Interelectrode capacitances, pF:
- input (cathode - first grid)
- output (cathode - anode)
- through passage (mesh first - anode)
- checkpoint (grid first - grid third)
25
21
one
32
26
0.1
four
Limits of change of anode current, mA
45
Anode power, W
600
Equal frequency, MHz
fifty
Resistance in the anode circuit, Ohm
2000