Sharp DV-NC70U Service Manual page 23

Note:
Whenever replacing the reel disk, perform the height check-
ing and adjustment.
Master plane
Reel disk
10 0.2mm
Reel disk
Figure 8-6.
8-8 CHECKING AND ADJUSTMENT OF TAKE-
UP TORQUE IN FAST FORWARD MODE
• Remove the cassette housing control assembly.
• After short-circuiting between TP803 and TP802
provided at operation PWB, plug in the power cord.
• Setting
1. Set a torque gauge to zero on the scale. Place it on the
take-up reel disk.
2. Press the FF button.
3. To calculate the remaining capacity of the play back
mode, slowly rotate the supply reel disk, and then shift
it into the forward mode.
• Checking
1. Turn the torque gauge slowly (one rotation every 2 to 3
seconds) by hand in the CW direction.
2. Make sure that the indication of torque gauge is not less
than 25mN·m (255gf·cm).
Torque gauge
25mN·m (255gf·cm)
or more
Idler ass'y
Figure 8-7.
• Adjustment
1. If the FF winding-up torque is less than the specified
value, clean the capstan D.D. pulley, reel belt, and
limiter pulley with cleaning liquid, and check again.
2. If the torque is less than the set value, replace the reel
belt.
Reel disk height
adjusting jig
Mechanism chassis
A
B
CW
The gauge is held at
its maximum value.
(Red mark)
Notes:
1. Hold the torque gauge by hand so that it is not moved.
2. Do not keep the reel disk in lock state. Do not allow long-
time measurement.
8-9 CHECKING AND ADJUSTMENT OF TAKE-
UP TORQUE IN REWIND MODE
• Remove the cassette housing control assembly.
• After short-circuiting between TP803 and TP802
provided at operation PWB, plug in the power cord.
• Setting
1. Set a torque gauge to zero on the scale. Place it on the
supply reel disk.
2. Press the rewind button.
3. To calculate the remaining capacity, slowly rotate the
take-up reel disk, and then shift it into the rewind mode.
• Checking
1. Turn the torque gauge slowly (one rotation every 2 to 3
seconds) by hand in the CCW direction.
2. Make sure that the indication of torque gauge is not less
than 25mN·m (255gf·cm).
Torque gauge
CCW
• Adjustment
1. If the rewind winding-up torque is less than the specified
value, clean the capstan D.D. pulley, reel belt, and
limiter pulley with cleaning liquid, rewind again, and
check the winding-up torque.
2. If the winding-up torque is still out of range, replace the
drive belt.
23
DV-NC70U/C
DV-NC72U
25mN·m (255gf·cm)
or more
The gauge is held at
its maximum value.
(Red mark)
Supply reel disk
Idler ass'y
Figure 8-8