Fluke Biomedical 35080M User Manual

Page 63

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35080M
Operators Manual

C-4

4. For all subsequent measurements at other generator settings, use the following procedure. First,

obtain a reading using the Linear Mammo Filter Pack (37351). Next, determine the actual kVp
using the look-up-table at the end of this application note. Finally, add the K-edge correction value
calculated in step 3 to this value. This procedure will allow kVp measurements over the range of
about 25 to 35 kVp. The example at the end of this addendum show a sample measurement
session with all of the appropriate corrections applied.

5. When using an oscilloscope as the readout device for the kVp divider, first convert all measured

voltages to kVp using the standard gain and offset for each filter pack. Then these measured
values can be converted to actual kVp values using Tables C-1 and C-2.

Example: The chart below gives a set of sample kVp measurements made following the procedure
outlined previously.

K-edge

reading

uncorrected

K-edge

reading

corrected

(Table C-1)

Linear pack

reading

uncorrected

Linear pack

reading

corrected

(Table C-2)

K-edge

correction

value

Corrected kVp

measurement

27.8 28.2 34.3 28.7 -0.5 28.2

32.2

26.1

same as

above*

25.5

38.3

33.5

33.0

* Once the K-edge correction value is determined, all subsequent measurements in the same session

will use this same value. It is not necessary to repeat the K-edge measurements in the same
session unless the Model 35080M kVp Divider is moved.

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