Wireless Geiger Counter - Trouble Obtaining Data

Trouble Obtaining Geiger Counter Data

Trouble Obtaining Data

Issue: Counts for GM counter lower or different than expected

Possible Cause: Dead-time: With any GM tube, there is a deadtime associated with any count where the device is not able to detect a radioactive particle or photon moving through the tube. To determine if there are lost counts due to the dead-time of the tube, Increase the distance between the GM tube and the sample and determine if the resulting consecutive counts adhere to the inverse square law. If you find two consecutive point that adhere to the inverse square law, then there is a sufficiently low missed count rate that proper data collection can occur.

Possible Cause: Maximum value for single sampling period exceeded: The maximum value for the count for any time step within PASCO Capstone is 65535. If your recorded counts are significantly different than what is expected, please shorten the sampling period. As you shorten the sample period further, when you have a sample count rate (counts/s) that agrees between two adjacent sampling rates (Hz or sample period in time), the longer period of those two samples will be the longest period over which you should collect counts for that sample under those experimental conditions. 

Issue: Having trouble with saving Data, after setting the start and end conditions to count for a fixed time.

Cause: This is an indication that the Start Condition was never met. In that case, no run is recorded.

If you want to count for a specific amount of time, display Count Rate (counts/sample) and set the Sample Rate on the Sampling Bar at the bottom of the screen to 30 seconds (as an example). Then the total counts for 30 seconds will be displayed after 30 seconds and then the total counts for the next 30 seconds will be displayed after 60 seconds, etc.

If you only want to sample for 30 seconds and then stop, open the Geiger Counter Tool at the left and check the box for “Record only one interval”.