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is suggested but any valid directory is acceptable. This directory will be
created in the images directory.
Example: newmod="m195_T5p9_vrf_m0p2__20070829"
Explanation:
o m195: Preferably set the module number of the detector (for 1
module systems only)
o T5p9: Energy of the illuminating x-rays, e.g. 5.9 keV
o vrf_m0p2: Vrf = -0.2, Setting of the analog amplifier
o yyyymmdd: Date of the calibration
The system will now run through the Vcmp scan. The next prompt will occur in
about 5 minutes. Vcmp (comparator voltage) should be set such that all pixels
are counting 100% of the incoming X-rays. The appropriate level of Vcmp can
be determined from the “mean_vs_vcmp” graph (Figure 16). Set vc to a level
well above the inflection point of the S curve: e.g. Vcmp = 0.65, where all
pixels are counting.
Figure 16 Result of the Vcmp scan.
The system will now run through a Vtrm voltage scan. All 6 trimbits are set to
63 and Vtrm is varied. You are now asked to enter a value of Vtrm such that
all pixels are counting 0% of incoming X-rays. The appropriate level of Vtrm
can be determined from the “mean_vs_vtrm” graph (Figure 17). Set Vtrm to a
level well below the inflection point of the S curve, e.g. vt=1.35, where no
pixels are counting. However the procedure suggests a value that is almost
always correct.
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