GS31b 
Triode 
The GS31b triode fulfills generation and amplification functions in
groundedgrid circuits in continuous wave operation in the decimetric and metric wavelength
ranges. It is physically identical to the GS1b, but with minor electrical differences.

GENERAL  
Cathode: indirectly heated, dispenser, oxidecoated.  
Envelope: metalceramic.  
Cooling: forced air.  
Height, mm, at most:  with heat sink: 147 
without heat sink: 134  
Diameter, mm, at most:  with heat sink: 100.2 
without heat sink: 65  
Mass, kg, at most:  with heat sink: 1.2 
without heat sink: 650 
A  anode; C  grid; KP  cathode and heater; P  heater 
ENVIRONMENTAL OPERATING CONDITIONS  
Vibration loads:  
frequency, Hz  52,000 
acceleration, m/s²  98 
Multiple loads with acceleration, m/s²  343 
Single impacts with acceleration, m/s²  1,470 
Linear loads with acceleration, m/s²  490 
Ambient Conditions:  
Temperature, °C  60 to +70 
Relative humidity at up to +40 °C, %  98 
NOMINAL ELECTRICAL PARAMETERS  
Heater voltage, V  12.6 
Heater current, A  3.4 
Mutual conductance (V_{a} = 2KV, I_{a} = 250mA, change in V_{g} = 1V), mA/V, at least  22 
Operating point (negative V_{g} with V_{a} = 2KV, I_{a} = 250mA), V  9 
input capacitance, pF  21.5 
output capacitance, at most, pF  4.5 
transfer capacitance, pF  0.12 
Warm up time, s, at most  120 
Output power, V_{a} = 1.8KV, I_{a} = 500mA, wavelength 60 cm, W:  >360 
Output power, V_{a} = 1.7KV, I_{a} = 700mA, wavelength 30 cm, W:  >180 
Designed Tube Life (hours)  >1000 
ELECTRICAL PARAMETER LIMITS  
Heater voltage, V  1213.2 
Heater current, A  3.13.7 
Operating point (negative V_{g} with V_{a} = 2KV, I_{a} = 250mA), V  612 
input capacitance, pF  1924 
output capacitance, pF  3.85.2 
Maximum CW Anode voltage (V_{a}), KV:  3 
Maximum Instantaneous value Anode voltage (V_{a}), KV:  6 
Instantaneous value Grid voltage (V_{g}), V  400 to +120 
Maximum CW Cathode current (I_{c}), A  1.4 
Anode Dissipation, W:  1.0x10^{3} 
Grid Dissipation, W:  22 
Temperature at anode lead, °C  200 
Temperature at cathode and grid leads, °C  120 
Temperature at external ceramic parts, °C  250 
Wavelength,cm  28100 
Averaged Characteristic Curves: U_{f} = 12.6V; _______ anode; _ _ _ _ gridanode 
Averaged Characteristic Curves: U_{f}= 12.6V; _______ anode; _ _ _ _ gridanode 
Averaged Characteristic Curves Showing Output Power and Efficiency versus Anode Current: U_{f} = 12.6V; L = 30cm; _______ output power (P); _ _ _ _ efficiency (n) 
Averaged Characteristic Curves Showing Output Power and Efficiency versus Anode Current: U_{f} = 12.6V; L = 30cm; _______ output power (P); _ _ _ _ efficiency (n) 