Appendix B Calibration (DiRex System)
Revision W HF Series X-ray Generators - Service Manual
B-32 Quantum Medical Imaging, LLC
Filament Offset Calibration
This procedure establishes the filament current offset and gain corrections.
Filament current measurement accuracy is verified using a pre-calibrated
Dynalyzer (or equivalent), non-invasive kV meter, or mAs meter as a bench-
mark. Ensure precision of the measurement instrument is sufficient enough
to assure generator accuracy requirements can be met. The Filament Offset
Calibration procedure may be performed using an oscilloscope, however, it is
not the preferred method. Using this method, the objective is to achieve the
"flattest" possible large and small filament waveforms, with no spikes or
peaks as shown in Figure B-20 below.
Figure B-20. Filament Offset Current Measurement (Using an Oscilloscope)
FLAT
CURVE, NO
PEAKS
FLAT
CURVE, NO
PEAKS