Fluke Biomedical 4000M+ - Manual (Page 22)

Victoreen 4000M+
Operators Manual
3-4
3.4 Sensitivity Selection
Sensitivity selection depends on the type of measurement required, as follows:
• Select HIGH sensitivity for dental, mammography, and other measurements requiring increased
sensitivity. (Detector sensitivity is increased by a factor of 20.)
NOTE
When the unit is in the Fluoroscopic Mode
(FLUORO), the detector sensitivity is always high,
regardless of the front panel HIGH/LOW Switch
setting.
• Select LOW sensitivity for standard radiographic measurements.
TUBE ANODE (TARGET)/FILTER SELECTION
The tube anode (target)/filter selection depends on the X-Ray machine being tested:
• Select Mo/Mo for molybdenum anode mammography machines.
• Select W/Al for standard radiographic machines.
NOTE
When using the 4000M+ with the Tube Anode
(Target)/Filter Selection Switch set to Mo/Mo, set
the filter wheel to the 21-50 kVp position.
3.5 Detector Positioning
The proper detector positioning depends on the application as discussed in the following paragraphs.
Radiographic Measurements
For a radiographic x-ray beam, position the detector as follows:
1. Position the detector on the x-ray table with the black plastic disk facing the x-ray tube.
NOTE
To eliminate measurement error due to the “heel”
effect, position the Model 4000M+ so that the front-
to-rear panel axis is parallel to the tube anode-to-
cathode axis.
2. Position the x-ray tube with the tungsten target approximately 66 centimeters (26 inches) away
from the top of the black plastic disk.
NOTE
The optimum distance is 66 centimeters (26 inches)
for most measurements. See Appendix A for a
discussion of source-to-detector distance (SDD).