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CV2349 gas-filled arc discharge tetrode

This valve measures 70x17mm overall and has a B7G base

This is an arc discharge tetrode with a cathode designed for pulse operation. It is equally suited as a strobotron. It is based on the EN30.

Max D.C. anode voltage400V
Min D.C. anode voltage250V
Max peak anode current (a)250A
Max mean anode current50mA
Peak inverse anode voltage250V
Trigger voltage (b)80 to 130V
Max average grid current10mA
Max flashing frequency250 per sec
Ambient temperature range-35 to +60°C
Starting characteristics (b)
Min trigger current (Va=400)50µA
Min trigger current (Va=250)300µA
Max delay time (c)40µs
Typical operating conditions as a stroboscopic source
D.C. supply voltage330V
Screen voltage70V
Trigger pulse amplitude (d)150V
Charging resistor6000 ohms
Discharge capacitor (µF) for operation at (Hz): 
6 to 352
30 to 501.5
45 to 801.0
80 to 1500.5
140 to 2500.3

(a) A minimum of 5A is necessary for the formation of an arc discharge with a tube drop of approx. 20V. if the main gap current is less than 5A peak, a glow discharge is likely to form with a 70V drop and result in excessive cathode dissipation.

(b) For triggering between Grid 2 and Grid 1, with Grid 2 positive with respect to grid 1

(c) Less than 40µs dependent on circuit conditions. With higher energy pulses the delay time can be considerably reduced

(d) With 100µs square pulses, negative with respect to Grid 2. Narrower pulses require a higher amplitude

1Grid 1
7Grid 2
Top capAnode

Inside view