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CV2434 / Z803U high-stability long-life gas filled trigger tube

Size This valve measures 41x20mm and has a B9A base


Nominal trigger ignition voltage 132V
Max working anode voltage 290V
Min working anode voltage 170V
Nominal anode/cathode maintaining voltage 105V
Typical trigger/cathode maintaining voltage 95V
Max priming current 25µA
Min priming current 2µA
Max peak cathode current 100mA
Max average cathode current (15 secs) 25mA
Max positive peak trigger current (*) 8mA
Max priming anode ignition voltage (darkness or daylight) 150V
Max transfer current (Va=240V) 25µA
Min trigger capacitance to ensure ignition with: (**)
Va=+170V 1500pF
Va=+200V 1000pF
Va=+240V 500pF
Max increase in trigger ignition voltage when
anode voltage is changed from 290 to 170V

Typical stability of trigger ignition voltage
2000 hour life (**)

+/- 1%


(*) Negative trigger current should not be drawn by the valve. Such a current occurs if the trigger potential is reduced below 90V during anode conduction.

To limit the positive peak trigger current a resistor of 2.2k ohm is required for trigger capacities between 4700 and 15000pF, and a resistor of 5.6k ohm for capacities greater than 15000pF

(**) To ensure high stability of characteristics in light and darkness a priming discharge of approx 10µA flowing between priming anode and cathode is essential. If the valve is used without priming discharge, delays in trigger ignition of up to 10 seconds may occur and thus appear to impair the stability of the characteristics. However under these conditions the pre-strike current of the valve is reduced considerably.



Pin Function
1 Anode
2 i/c
3 i/c
4 Cathode
5 Cathode
6 Priming anode
7 Cathode
8 Trigger
9 Trigger

The cathode connection should be made to pins 4, 5 and 7 together.