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CV2138 geiger muller tube

Size This tube measures 70x36mm overall.

This tube is marked No. 8938, Volts 1410, Window weight 7MGm/cm2. Equivalent to GM4 this uses ethyl formate as a quenching agent which gives better plateau characteristics and temperature coefficients.

Plateau length average250V
Plateau slope average0.05%
Operating voltage limits1250 to 1450V
Count life6x10^8
Shileded background counts7 to 15 per minute
Signal output220/100+C (*)
Dead time100µs
Recovery time250µs

*: C = the total capacitance across the tube in pF