Calibrate The Reading - GQ Electronics GMC-SE User Manual

Calibrate the reading

You do not need to do the calibration if you just want to qualitatively detect radiation.
However, if you have standard radiation sources with known µSv/h value, you may
calibrate the instrument to get accurate readings.
The factory default calibration value is for general in-door and out-door
measurements.
Calibration
Select Calibrate form the Main Menu. There are three points provided for calibration.
Each calibration point needs two values to be entered, the CPM value and the µSv/h value.
The user can enter up to six calibration points from large to high count rates.
Procedure:
1. Place the testing radiation source ~30mm away to the center of unit Geiger Tube
side. In Text or Graphic mode, wait for at least 3 minutes.
2. Note the CPM value.
3. Select Calibrate menu item on the device, then input both the CPM value you noted
and the known µSv/h value of the calibration source.
4. Wait for the popup window to close to save the data for this calibration point.
5. Continue with step 1 with other calibrated radiation sources.
Navigation keys:
Key1: Back/Exit
Key2: Increase the value by 10 CPM or 0.1uSv/h respectively
Key3: Decrease the value by 1 CPM or 0.01uSv/h respectively
Key4: Toggle input data type between CPM and uSv/h
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