The GM Counter Accessory is shown below. It can generate a DC voltage upto 1 KV using the 5V pulse generated on PWG. The duty cycle of the pulse is varied to control the voltage. The high voltage applied to the GM tube is divided by 200 and connected to CH0 for monitoring. The pulse generated by the GM counter when radiation passes through it is processed and given to CNTR input of Phoenix for counting. Click here for the circuit schematic.

GM counter experiments can be done using a GUI or the small Python programs gmcount.py and gmtubechar.py.

This screenshot shows the gamma radiation counts from a gas light mantle during 100 seconds.

Statistical distribution of gamma rays from ⁶⁰Co plotted by taking 100000 trials shown below

GM tube Voltage Vs Count Curve (Taken using a gas light mantle as gamma source)