Pioneer AVH-P6500DVD UC Service Manual page 134

1
Symptoms in case of poor adjustment: Error efficiency deteriorated: 10-3 (Optimum value: 10-4 or lower)
A
Caution: Avoid exposing your eyes to laser beams for a long time.
Preparation for adjustment: Clean both ends of the shafts.
Procedures:
1. Place the DVD mechanism module upside down.
2. After replacing the pickup (by referring to the procedures of " Removing the Pickup." ),
roughly adjust the three skew screws through visual check so that the pickup is mounted in parallel
to the CRG chassis around the inner and outer tracks.
3. Connect an oscilloscope as shown in the connecting diagram.
B
4. Turn on the power of the product. Load the test disc (GGV1018).
5. In the front-end test mode, set the disc type to DVD layer 1. Move the pickup toward the inner tracks.
6. Turn on the laser diodes.
7. With the focus servo closed, complete all automatic adjustments. Close the tracking servo, and
then complete all automatic adjustments.
8. Observing the RF waveform on the oscilloscope, slightly turn the skew adj. screw C to maximize the RF level.
Next, move the pickup toward the outer tracks. Slightly turn the skew adj. screw B to maximize the RF level.
Turn the skew adj. screws A and B in the same direction keeping their rotating angles the same until the RF level
becomes the maximum.
Lastly, move the pickup toward the inner tracks. Turn the skew adj. screw C so that the RF level
becomes the maximum.
Repeat the step 8 three times.
9. Turn off the power in the test mode. After confirming that the disc has stopped, eject the disc.
C
10. Apply Screw lock(GYL 1001) to the skew adj. screws and the shafts.
Skew adj. screw
Prevent applied Screw lock
D
from extending beyond this position.
E
F
134
1
2
High jitter of the RF signal
RF waveform deformed
Unstable operation in tracking closing and servo control
Use brand new skew screws supplied with the service kit CXX1639.
Screw lock(GYL 1001)
C
AVH-P6500DVD/UC
2
3
Shaft
Prevent applied Screw lock
from extending beyond this position.
B
A
3
4
Skew adj. screw
4