6 : M e c h a n i c a l a n d E l e c t r o n i c A d j u s t m e n t s
CHRISTIE
CHRISTIE
35/70 Service/PM Manual
March, 1997
Figure 6.5: Pulldown Sensor Test Point
After completing the above adjustment, check the 90-degree output by connecting the second channel of the scope to pin 3
of U19. The phase relation should be about 90 degrees, as shown in Figure 6.6. The quadrature relationship is required
when the projector executes high-speed slew motion operations. If adjustment is required the 2 screws securing the pull-
down encoder to the framing ring can be loosened, and the encoder moved up or down to achieve correct quadrature.
Pulldown
Signal (TP13)
Pulldown
Sensor
90-degree
Figure 6.6: Phase Relationship of Pulldown Quadrature Signal