Sharp DV-NC70U Service Manual page 33

8-22 REPLACING THE UPPER AND LOWER
DRUM ASSEMBLY
• Replacement (Perform in the numerical order)
1 Remove the motor as stated in 8-21 Replacement of
Drum D.D. motor.
2 Remove the drum earth brush ass'y 2.
3 Remove the upper and lower drum assembly from main
chassis 1.
4 Remove the drum FFC holder 3.
[Cares when replacing the drum]
1. Be careful so that the drum earth brush is not lost.
2. Do not touch directly the drum surface.
3. Fit gently the screwdriver to the screws.
4. Since the drum assembly is an extremely precise as-
sembly, it must be handled with utmost care.
5. Make sure that the drum surface is free from dust, dirt
and foreign substances.
6. After replacing the drum be sure to perform the tape
running adjustment.
After that, perform also the electrical adjustment.
• Playback switching point adjustment
• X-position adjustment and check
• Standard and x-3 slow tracking adjustment
7. After replacing the drum clean the drum.
2
1
3
Lower drum bottom side
Figure 8-35.
8-23 ASSEMBLING OF PHASE MATCHING
MECHANISM COMPONENTS
• Assemble the phase matching mechanism compo-
nents in the following order.
1. Assemble the reverse guide lever and pinch drive cam.
2. Mounting the shifter (on the back of the mechanism
chassis).
3. Mounting the master cam (on the back of the mecha-
nism chassis).
4. Assemble synchro gear.
5. Assemble the loading motor parts.
• PINCH DRIVE CAM AND REVERSE GUIDE
LEVER ASSEMBLING METHOD.
(Place the following parts in position in numerical order.)
(1)Pinch drive cam 1
(2)Reverse guide spring 2
(3)Reverse guide lever ass'y 3
(4)Open guide 4
4
Figure 8-36.
3
2
33
DV-NC70U/C
DV-NC72U
Insert it into the
groove of the shaft
3
Don't run up
on the spring
2
1
A
B
1
Synchro gear
From Top View