Define Calibrations
4.
The system will prompt for the Gain Calibration Standard to be selected.
Using the down arrow, select the
241
Am source to be used for this calibration
and press the
Enter
button.
5.
Enter the number corresponding to the source carrier in the sample changer,
which contains the gain calibration standard.
6.
At this point the system is ready to execute the gain calibration procedure.
Make sure that the gain calibration standard is in the source carrier specified
and that the source carrier is in the right sample stack (see the figure in
Loading Sample Carriers
on page 15).
7.
Press
Count
to initiate the procedure. The
i
Matic will advance the sample
changer to the gain source carrier, insert it into the detector cave and begin the
calibration sequence.
8.
When finished, the
i
Matic will display the message:
SYS GAIN ADJUST COMPLETE, Gain Error = 0. 00 %.
Press Enter to Accept or Cancel to Reject.
You should press
Enter
and accept this gain adjustment. Upon accepting the
gain adjustment, the system will restack the carriers if the auto-restack feature
is enabled. See
Auto-restack
on page 68.
Note: The
i
Matic will always be able to make a proper gain adjustment if the source
is
241
Am and the source activity plane is 4 mm from the PIPS detector face. If
an incorrect source was used or the source used was too far away from the
detector, the
i
Matic will not be able to achieve a 0 % error and this procedure
will need to be repeated.
Define Calibrations
Calibrations are performed by defining the procedures (background, alpha efficiency,
and beta efficiency) for any of the 10 available system calibrations, and running those
procedures. Each user procedure is associated with a system calibration and sample
data acquired in a user procedure will use that calibration to calculate activity. Data
records for all sample counts are maintained by
i
Matic until cleared by the user.
If an attempt is made to modify a calibration definition while data exists from a
procedure that used that calibration, you will be prompted with the following screen:
iMatic Automatic Counting System User's Manual - 9239221K
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