Detector Boards; Figure 5-11. Upper C-Arm Frus - Hologic QDR 4500 Technical Manual

Detector Boards

To remove and replace the Detector Boards refer to Figure 5-11 and follow the procedure below:
1. Turn off the QDR 4500 computer and instrument power switches, and main power
circuit breaker.
2. Remove the Integrator/Multiplexor Board (see procedure above).
CAUTION: Do not attempt to remove detectors without first removing the Mux board, as the
detectors may be damaged.
3. After the Mux board has been removed, loosen (do not remove) the screws on all three
detector boards (4 on each board).
4. Remove the screws on the detector board being replaced, and remove the detector
board.
5. Replace the detector board (reverse the steps) and the Mux board (see above procedure).
6. Perform the A/D Gain Control Adjustment in the Alignment and Calibration section of
this manual.
7. Perform Beam Flattening in the Alignment and Calibration section of this manual.
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QDR 4500 Technical Manual

Figure 5-11. Upper C-Arm FRUs

SQLW Mux Bd Assy
Center Metal Plate
Back Detector Bd
Middle Detector Bd
Front Detector Bd