HV power supply for Geiger-Mueller Tube

High Voltage Generator for Geiger Tubes

http://www.techlib.com/science/geiger.html

Output Voltage vs. Input, measured by me

 Icc[mA] @ no load
 
version 1
GM tube СИ3-БГ (SI3-BG) may be is not suitable for measuring the background radiation.
This tube  is not very sensitive, it counts less than 1 cpm   without any radiation sources around   ??!! (in my case HV=420V)