!
164 ATOMLAB 500 DOSE CALIBRATOR
The Semi-Automated Decay Test allows the user to begin a linearity test using the automated
test method while the activity level is high and then switch to the manual test method to
complete the test. This method prevents changing background levels from greatly affecting the
reading at low activity values. The switchover to manual mode defaults to 100 µCi. The switch
from auto to manual can be set from 50 µCi to 500 µCi.
To Perform A Semi-Automated Decay Test:
1. From the Linearity Testing menu, select <Semi-Automated Decay Test>. The Semi-Auto-
mated Decay Test screen is now displayed.
2. Select <Set Test Parameters>. The Semi-Automated Decay Test Set Test Parameters screen is
displayed. From this screen the user can set the reading interval and set the time until
normalized reading. Touch to highlight the desired setting and use the <▲> and <▼> keys
to adjust the value.
3. Select <Setup Options>. The semi-automated decay setup options screen is displayed. From
this screen the user can decide to perform the test using any of several methods including:
• Normalized reading by hours: allows the user to set the reading interval at a set number of
hours and set the time to be used for the normalized reading.
• Normalized reading by half-life of the isotope selected: allows the user to set the reading
interval by half-life and select which half-life reading will be used as the normalized reading.
• Averaging calculation method with readings at a set number of hours: allows the user to
set the number of hours between readings before the system calculates before the system
calculates the results using the averaging method described in Appendix J, Linearity.
• Averaging calculation method by half-life: allows the user to set the number of half-lives
between readings before the system calculates the results.
4. Touch to highlight the desired variance calculation method.
5. Touch to highlight the desired reading interval units.
6. Touch to highlight <Test Ends Below> and enter the activity level at which the test should
be ended. Touch <Enter> to record this value and return to the Semi-Automated Decay
Setup Options screen.
7. Automated Ends Below displays the default activity to end the automated portion of the
test. If the value displayed is not appropriate, touch <Automated Ends Below> and use the
keypad to enter an activity between 50 and 500 µCi at which the automated portion of the
test should end.
8. When all setup options have been addressed on the semi-automated decay setup options
screen, touch <Enter> twice to record all settings and return to the Semi-Automated Decay
Test screen. The live detector reading is displayed in red on the screen. If necessary, touch
<Zero Background> to perform a Zero Background reading at this point.
9. Place the Tc-99m, or another short half-life isotope, into the dipper and then place the dipper
with the source into the detector to perform the linearity test.
To Next Page
Loading...
