SIGMA BM-286A - Manual (Page 26)

3. OPERATING INSTRUCTIONS page 23
Model BM-286A
3.5.3. Detector Efficiency Check:
The Calculation Set-up box will appear and the operator will be prompted for a count time (in
seconds) and the calibration source activity (in nanocuries).
Press BEGIN at which time a START button will appear.
Press the START button and the unit will then take an nn second background.
The operator will be prompted to place the source in the center of the chamber.
Press START to accumulate an nn second count with the source in the chamber.
Calculate efficiencies of the detectors and the overall efficiency of the unit. The efficiencies are
displayed, but not stored. Overall efficiency which is the sum of the efficiencies for the six
plastic detectors is calculated with a test source in the center of the counting chamber.
3.5.4. Operator Setup:
Operators can be deleted or added by name, badge number, password and level of accessibility
(Admin. or User). Be careful in selection of administrative access.
3.5.5. Shut Down:
Pressing this button will close the program and release the computer back to the Windows NT
environment.
3.5.6. Detectors, Scale, and Disc.:
This window provides us with a troubleshooting tool as well as a way to adjust the upper and
lower level discriminators. Refer to Discriminator Adjustment (section 5.3.) for detailed
instructions.
The detector counts and scale weight are displayed and updated every two seconds.