Hologic DISCOVERY A, Technical Manual

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Discovery QDR Series Technical Manual
5-33
5.8.4 Rotary Potentiometer
To remove and replace the Rotary Potentiometer (included in the cable assembly 180-
0267), refer to Figure 5-16 and follow the procedure below:
1. Shut down the computer and then turn off the main circuit breaker on the foot end
pedestal.
2. Remove the Aperture Position Belt (refer to the procedure above).
3. Remove the potentiometer pulley.
4. Remove and replace the potentiometer (face wires towards the Aperture Motor
PCB).
5. Replace the potentiometer pulley (pulley goes all the way down on the shaft).
6. Refer to the Aperture Position Belt procedure and replace the belt.
7. Turn on the Discovery power, boot the computer and login as Service.
8. Perform “Aperture Calibration ” on page 4-9.