GU88A
TRIODE
The GU88A triode is a RF oscillator and power amplifier tube for use in stationary generalpurpose RF equipment.
GENERAL
Cathode: directly heated, carbonized thoriated tungsten.
Envelope: metalceramic.
Cooling: water for anode, forced air for envelope other elements.
Height: at most 764 mm.
Diameter: at most 215 mm.
Mass: at most 33 kg.
K1, K2  cathode; C  grid; A  anode
BASIC DATA Electrical Parameters 

Filament voltage (AC or DC), V  26 
Filament current, A  640720 
Output power at frequencies up to 22 MHz, kW, at least  500 
Mutual conductance (at anode voltage 1 kV, peak grid voltages 200 and 600 V), mA/V  380620 
Cathode emission current, A, at least  500 
Static amplification factor (at anode voltages 1 and 2 kV, anode current 10 A)  3654 
Interelectrode capacitance, pF:  
gridanode, at most  200 
gridcathode, at most  500 
anodecathode, at most  7.5 
Limit Operating Values  
Filament voltage (AC or DC), V  2426 
Filament starting current (peak value), A  1,150 
Anode voltage (DC), kV  12 
Negative bias voltage, absolute value, V  500 
Dissipation, kW:  
anode  400 
grid  7 
Operating frequency, MHz  30 
Envelope temperature at hottest point (except for anode), °C  175 
Averaged Characteristic Curves:
_____ anodegrid;
_ _ _ grid