Fluke TRACKERTM 90100 - Manual (Page 23)

Operation
Operation Instructions
2
2-11
NOTE
NOTE
The FPGF for the center ion chamber is displayed
on the bottom line of the VFD.
Use the UP and DOWN buttons to toggle the FPG annunciator on or off. The FPG annunciator in the
upper right-hand corner of the display signifies that FPG corrections are enabled, see Figure 2-15. When
the FPG annunciator appears, the 35360A TRACKER Display multiplies each ion chamber's exposure
value by its FPGF before displaying the reading. See section 2.4.10 for information on how to set the
front panel gain factors.
2.4.8 Using the MEASURE SELECT Button (Normal Mode)
Press the MEASURE SELECT to display the Measurement screen. The 35360A TRACKER Display can
present the measurement data in an absolute form, or as a percentage of the center ion chamber. While
the Measurement screen is displayed, press the MEASURE SELECT button to toggle the display mode
between the percentage-of-center and absolute presentations.
2.4.8.1 Absolute Measurements
Figure 2-15 shows the ion chamber layout for the Measurement screen in the absolute display mode.
The 35360A TRACKER Display displays the four outside ion chamber readings in a diamond pattern
above the center channel. All five readings are in the selected units ("rads" in this case).
top
left right
bottom
center units
Figure 2-16. Measurement Screen Showing the Ion Chamber Layout
The measurement value corresponding to the
central ion chamber is always displayed on the
bottom line of the VFD.
Figure 2-17. An Absolute Dose Measurement With Air Density Corrections and the Front Panel Gain
Factors Enabled