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CV1787 / FX2505 hydrogen thyratron

Size This valve measures 175x60mm overall and has a 4 pin base.


Heater voltage 6.3V
Heater current 6.0A
Max peak anode voltage 8kV
Max DC anode supply voltage 2.5kV
Max PIV 8kV
Max peak anode current 90A
Min trigger voltage 175V
Max negative grid voltage 200V
Max mean anode current 100mA
Max rate of rise of anode current 1000A/µs
Max value of product of peak anode voltage, peak anode current and pulse repetition rate 2x109 VxAxPPS
Min cathode heating time 3 mins
Ambient temperature range -50 to +90C


Pin Function
1 Grid
2 Heater + cathode
3 Heater
4 Cathode
TC Anode