Quantum ODYSSEY HF Series, Service Manual

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Appendix B Calibration (DiRex System)
HF Series X-ray Generators - Service Manual Revision W
Quantum Medical Imaging, LLC
B-47
Film Screen Selection
Calibration of film/screen combinations should be performed in the following
sequence, assuming a typical radiographic system having one ion chamber in
the wall stand (72" and 40" SID), and a second ion chamber used in the
radiographic table (40" SID).
If the system is using a wall stand and 200 and 400 speed films, calibrate the
Wall 72" film screen combination using 200 speed film first, followed by Wall
72" using 400 speed film.
If the system only has a table receptor, perform all AEC calibrations (i.e., ion
chamber balance, AEC MAS balance, AEC optical density, and AEC KVP proce-
dures).
IMPORTANT NOTE: Typically, the AEC calibration
parameters for each of the various receptors used
with the generator are quite similar. Therefore, the
HF Series generator’s calibration data "Copy Film
Screen" function can be used to copy the calibration
parameters from one receptor (i.e., a calibrated
receptor) to the other receptors. For example, after
completing AEC calibration of 72" Wall film/screen,
the Copy Film Screen function can be used to copy
the 72" film/screen calibration data to 40" Wall
film/screen.
After copying AEC data, the only further AEC cali-
bration usually required for the 40" film/screen is
performing AEC OD Calibration to set the "AEC Ref"
value. Similarly, the 40" Wall film/screen calibra-
tion data can be copied to the 40" Table, however,
the table ion chamber’s MASTER GAIN potentiome-
ter must be adjusted as required. Be sure to verify
the AEC films for each SID/receptor meet applica-
ble regulatory agency requirements. If required,
further optical density accuracy can be attained by
performing the "AEC KV Calibration" procedure.