Thermo Scientific LevelPRO, User Manual

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Startup & the Setup Wizard
The Setup Wizard
Thermo Scientific LevelPRO User Manual 3-9
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Isotope – The isotope option allows the program to select the appropriate half-
life for the radioactive material and to properly correct for the natural decay of
the source over time. The isotope is stamped on the identification plate on the
source housing. Almost all of the sources supplied by Thermo Fisher are
Cesium 137 (Cs-137) with a 30-year half life. When the isotope is not known,
it is usually wise to select Cs-137 as the option.
Note: Selecting the wrong isotope will not affect the initial calibration, but
will result in a small measurement error with time.
9. After making the appropriate selections on this screen, click the Next button to
enter the detector’s length and units.
Figure 3-7. Detector Length/Unit
10. Click the Next button to move to the next screen.