GU93 B
TETRODE
The GU93B tetrode is used for RF power amplification at frequencies up to 250 MHz in generalpurpose television transmitters.
GENERAL
Cathode: indirectly heated, oxidecoated.
Envelope: metalceramic.
Cooling: forced air.
Working position: any desired.
Height: at most 145 mm.
Diameter: at most 116 mm.
Mass: at most 3.5 kg.
A  anode; KP  cathode and heater; P  heater; C1  grid 1; C2  grid 2
OPERATING ENVIRONMENTAL CONDITIONS  
Vibration loads:  
frequencies, Hz  135 
acceleration, m/s²  4.9 
Multiple impacts with acceleration, m/s²  147 
Ambient temperature, °C  155 
Relative humidity at up to +25 °C without moisture condensation, %  80 
BASIC DATA Electrical Parameters 

Heater voltage (AC or DC), V  12.6 
Heater current, A  9.512 
Mutual conductance (at anode voltage 700 V, grid 2 voltage 400 V, anode current 3,000 mA), mA/V  75125 
Zero anode current (at anode voltage 700 V, grid 2 voltage 400 V, grid 1 voltage 0), A, at least  4 
Negative cutoff voltage, absolute value (at anode voltage 4,000 V, grid 2 voltage 400 V, anode current 20 mA), V, at most  240 
Interelectrode capacitance in agroundedcathode circuit, pF:  
input, at most  100 
output, at most  20 
transfer, at most  0.1 
Limit Operating Values  
Heater voltage (AC or DC), V  13.212 
Anode voltage, V:  
DC  3,800 
instantaneous value  6,500 
Grid 2 voltage (DC), V  450 
Negative grid 1 voltage (DC, absolute value), V  250 
Anode current, A:  
DC component under conditions of class Â  2 
instantaneous value in the sync pulse mode  9 
Grid 1 current (DC component), mA  100 
Dissipation, W:  
anode  4,000 
grid 2  20 
grid 1  5 
Operating frequency, MHz  250 
Minimum cathode heating time, s  240 
Temperature at hottest point of envelope, °C  200 
Averaged Anode Characteristic Curves:
U_{f} = 12,6V; U_{g2} = 400V
Averaged Characteristic Curves:
U_{f} = 12.6V; U_{g2} = 400V;
_____ anodegrid;
_ _ _ grid 2;
_ . _ grid 1
Averaged GridAnode Characteristic Curves:
U_{f} = 12.6V; U_{g2} = 400V