Sharp DV-NC65H, Service Manual

Page: 29 / 113

29
DV-NC65H/S
DV-NC70H
Set value LP 6.9 mN
⋅
m (70 gf
⋅
cm)
• Checking
1. Make sure that value is within the setting 6.9 mN·m
(70 gf·cm).
2. The winding-up torque fluctuates due to variation of
rotation torque of limiter pulley ass'y. Read the center
value of fluctuation as setting.
3. Set the LP record mode and make sure that the winding-
up torque is within setting.
• Adjustment
If the playback winding-up torque is not within the setting,
replace the limiter pulley assembly.
8-10. CHECKING AND ADJUSTMENT OF TAKE-
UP TORQUE IN RECORD/PLAYBACK
MODE
• Load the cassette torque meter into the unit.
• Press the picture record button, and set LP picture
record mode.
Figure 8-9.
+20
–25
+2.0
–2.5
+2.0
–2.5 +20
–25
Cassette torque
meter
8-11. CHECKING AND ADJUSTMENT OF TAKE-
UP TORQUE IN VIDEO SEARCH REWIND
MODE
• Remove the cassette housing control assembly.
• After short-circuiting between TP803 and TP802 pro-
vided at VCR Operation PWB, plug in the power cord.
• Setting
Press the playback button and rewind button to set the
video search rewinding mode.
• Checking
Place the torque gauge on the supply reel disk, and turn it
counterclockwise very slowly (one rotation every 1 to 2
seconds) and check that the torque is within the set value
14.1
±
3.5mN
⋅
m. (144
±
35gf
⋅
cm)
Figure 8-10.
Note:
Surely put the torque gauge on the reel disk to measure. If
the torque gauge is raised, accurate measurement is
impossible.
• Adjustment
If the rewinding playback winding-up torque is not within the
setting, replace the limiter pulley assembly.
Note:
The winding-up torque fluctuates due to variation of rota-
tion torque of supply reel disk. Read the center value of
fluctuation as setting.
Torque gauge
Supply reel disk
CCW