FD-934S is high power ceramic-metal 
dynatron with thoriated tungsten cathode and 
water cooling anode. With a maximum anode 
dissipation of 130kW, and a maximum working 
frequency 10MHz, it is widely used as an 
oscillator for industrial high frequency heating. 
General characteristics 
Electrical characteristi cs 
Filament…………cathode thoriated tungsten 
Filament voltage…………………………12V 
Filament current…………………………420A 
Transconductance……………………82mA/V 
Amplification factor………………………30 
Oscillatory power……………………200kW 
Interelectrode capacitances:: 
Grid-cathode…………………………185pF 
Anode-cathode………………………3.4pF 
Anode-grid…………………………110pF 
Mechanical characteristi cs 
Operating position………Vertical, anode down 
Height(max.)…………………………690mm 
Diameter (max.)………………………250mm 
Weight (max.)……………………………30kg 
Transportation & Operating position: 
…………Vertical, anode down 
Coolin g 
Cooling methods…combination of water & air 
Anode water flow…………………≥220L/min 
Total air flow of Mandri, radiator & ceramic 
crust…………………………………≥450m3/h 
Temperature on seal of glass and 
metal.(max.)…200℃ 
Maximum ratings 
Filament voltage…………………………12V 
Start current of filament ……………630A 
Anode voltage ………………………… 15kV 
Anode DC current………………………22A 
Anode dissipation power………………130kW 
Grid dissipation power…………………5kW 
Working frequency……………………10MHz 

Typical operation 
Working frequency……………………300kHz 
Anode DC voltage………………………13kV 
Grid DC voltage………………………-800V 
Anode DC current………………………21A 
Anode DC current………………………3.4A 
Prompting power………………………5100W 
Prompting voltage……………………1500V 
Anode output power…………………200kW