Fluke TRACKERTM 90100 - Manual (Page 27)

Operation
Operation Instructions
2
2-15
2.4.10.1 Changing Front Panel Gain Factor's From the Measurement Screen
The five FPGF's may be set by adjusting the measurement readings to achieve a set of desired values.
Press the MEASURE SELECT button until the desired Measurement screen is displayed. Press the
GAIN SELECT button to advance the "X" cursor among the five measurement values. Next use the UP
and DOWN buttons to adjust the selected measurement value.
When the measurement values are displayed in the absolute form, see Figure 2-26, pressing the UP or
DOWN arrow increments or decrements the selected chamber's FPGF. For example, increasing the left
dose value by 2% will increase the left FPGF by
2%.
Figure 2-26. An Absolute Dose Measurement With the Center Ion Chamber Selected for FPGF
Modification
When the measurement values are displayed in the percent-of-center form, see Figure 2-27, and the "X"
cursor is pointing at one of the percentage values, pressing the UP or DOWN arrow will increment or
decrement the selected chamber's FPGF. For example, increasing the left percentage value by 2% will
increase the left FPGF by 2%.
When the measurement values are displayed in the percent-of-center form and the "X" cursor points to
the center ion chamber's absolute measurement value, pressing the UP or DOWN arrow increments or
decrements all five of the FPGF's. This causes the FPGF of the center channel to increase, while
allowing the four peripheral ratios to remain unchanged. For example, increasing the center chamber's
absolute dose value by 2% will increase all five of
the FPGF's by 2%.
Figure 2-27. A Percentage Dose Measurement With the Left Ion Chamber Selected for FPGF
Modification
2.4.10.3 Saving the FPGF Changes
To save any changes made to the FPGF's, press and hold the GAIN SELECT button for approximately
three seconds. These settings become permanent and will be used when the 35360A TRACKER Display
displays the FPG annunciator.
2.4.10.4 Aborting the FPGF Changes
To abort any changes made to the FPGF's, turn off the instrument while in the Gain Setting Mode. This
causes the 35360A TRACKER Display to discard the new FPGF settings and use the values previously
stored.