Radiation Alert Inspector + Manuel D'instructions page 19

21. Turn the Inspector+ off. Hold down the "+" button while turning the
Inspector+ on. The numeric display will show a single number.
23. Press the "+" or "-" button until 7 is shown on the numeric display.
24. Push the Set button.
25. The calibration factor is displayed. Press the "+" or "-" buttons to adjust
the calibration factor to the average calibration factor calculated in Step 20.
26. Push the Set button to enter the new setting and resume normal operation.
The calibration factor is set to 100 (percent) at the factory. If you change the
reading, for example, to 20% higher than the factory reading, the new calibration
factor would be 120. The current calibration factor is displayed during the system
check when the Inspector+ is first turned on.
Calibrating Electronically
You can calibrate electronically using a pulse or function generator. Electronic
calibration requires a cable with a 2.5 mm plug, with the tip carrying the signal.
Follow these steps:
1. Set the signal height to 3.3 volts and a negative pulse width of 85
microseconds positive pulse.
CAUTION: Do not inject a pulse when the Inspector+ is turned off.
Do not exceed 5 volts.
2. Turn on the Inspector+ and set the mode switch to mR/hr µ µ Sv/hr.
3. Plug the cable into the upper jack.
4. Use the following table to check the Inspector+'s accuracy. The table shows
appropriate pulse generator count rates to calibrate for Cs-137. If the
accuracy is not within desired limits, follow steps 5-7. Note that the
Inspector+ automatically compensates for lost counts due to GM tube dead
time. Thus, the display reading in CPM mode will not equal the input
frequency. You can display uncompensated counts in the CPM mode by
continuously holding down the "-" button. The reading will now correspond to
the input frequency.
19