Stat Fax 303 Plus, Operator'S Manual

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Awareness Technology, Inc. Stat Fax 303 Plus Operator’s Manual Rev. J 31
“Set Carrier to X”, “Then Press Enter” is displayed, where X is either 1 or A, depending on the
strip type. Load the first strip into the right-most carrier position and press ENTER. While the
strip is being automatically positioned for reading, the display will indicate “
Positioning Strp” .
After the strip or strips containing the standards are read, there will be a pause after the standard
curve is read. The display will prompt “
PLOT CURVE Y/N” . Press YES to plot the curve. Press
NO to continue without printing the curve.
If calibrators were read in duplicate, you may choose to edit the curve. The display will prompt
“
DELETE WELLS Y/N” . Use the YES or NO key to answer. If you press NO, the instrument will
proceed to read and calculate the remainder of the strips. If you choose to edit the curve by
pressing the YES key, the display will ask for the location of the well(s) that are to be deleted.
Enter the wells one by one. You may delete as many as one from each pair,
but you may not
delete an entire point . When you have finished deleting wells, press the ENTER key again. The
standard curve will be recalculated showing an “X” beside the deleted well(s). If one of a
duplicate pair is deleted, the remaining point will be considered as the value for that standard.
Again the operator will have an opportunity to see the graph and to edit. This may be repeated
as many times as desired until either an acceptable curve is obtained, or the mode is canceled.
To read and calculate specimens, answer NO to the question
“DELETE WELLS Y/N” .
The instrument will be ready for the next strip when it displays “Set Carrier” , “Then Press
Enter” . To continue reading in the Point-to-Point mode, load the next strip and press the
ENTER key.
Press CLEAR twice to cancel the mode.
2.2.7 % Absorbance Multi-Point Mode
Press the %ABS key. The % Absorbance Multi-Point Mode (%A/A
0
Multi-Pt.) is a multi-point
calibrator mode that allows the operator to enter several different calibrator concentrations.
These are used to calculate the concentrations of unknown samples according to Beer’s Law.
The resulting calibrator curve is a series of line segments connecting the calibrator points, which
is similar to the point-to-point mode. In addition, the calibrator with the highest absorbance (A
0
calibrator) is assigned a value of 100%, and all samples have an additional reported value of
100*(sample Abs / A
0
Cal Abs).
Unknown samples are calculated as in the point-to-point mode (see section 2.2.5). The
additional %A/A
0
calculation is made as above, and printed on a second sample data line.
Note: The calibrators’ absorbances must be decreasing down the strip; i.e., the first
calibrator is the darkest, the second must be the next darkest, etc. The plotted curve
shows absorbance vs. %A/A
0
.
Note: If you are using a stored curve, you must still run the A
0
calibrator to recalibrate the
stored curve. All samples will be calculated using the stored %A/A
0
values for the curve
and the newly-run A
0
calibrator absorbance.
Except for the differences mentioned above, please follow the procedures for running the Point-
to-Point mode to proceed in this mode.