Sharp VC-90ET - Page 26

VC-9O0ET
f) Push the (+) or (-) tracking button to check
that a flat response is obtained on the
envelope waveform.
g) Secure the guide roller by tightening the
guide roller setscrew in the unloading mode.
h) Play back the tape drive train alignment tape
to check that the envelope waveform does
not change.
8. Adjustment of A/C head X-position.
a) Push the (+) and (-) tracking buttons at the
same time to the preset mode.
b) Rotate the X-position adjusting nut with an
adjusting box driver, and adjust the A/C head
position for maximum head switching pulse
low side envelope.
c) Adjust the playback switching point.
d) Check the flatness of the envelope waveform
and sound by playing back a recorded tape.
X-position adjusting nut
AC head
A 4
een =
Main chassis
Figure 1-62.
REPLACEMENT OF THE CAPSTAN D.D.
(DIRECT DRIVE) MOTOR
@ Remove the cassette housing control assembly.
® Removal (Follow the order of indicated
numbers.)
Remove the three screws.
Capstan D.D.motor
la control PWB
Remove the reel belt.
Figure 1-63.
MR element
Remove the FFC.
e Reassembly
1. Mount the capstan motor on the mechanism
chassis making sure not to allow the capstan
shaft to hit the mechanism chassis, and attach it
with the three screws.
2. Insert the FFC into the capstan D.D. motor
control PWB.
3. Attach the reel belt.
Notes :
1. After installing the capstan D.D. motor, be sure
to rotate the capstan D.D. motor and check the
movement.
2. Check and adjust the servo circuit.
REMOVAL AND REASSEMBLY OF THE
LOADING GEAR BLOCK
Notes : The following explanation is based on 4-
head models. (The slow brake spring and
slow brake lever are not provided on 2-
head models.)
1. Remove the cassette housing control assembly.
2. Remove the reel belt.
3. Remove the reel block.
@ Removal
Notes :
1. Use care not to deform the parts hooked to the
slow brake shaft cap, take-up loading gear, and
supply loading gear as shown in Figure 1-64.
8-4
Figure 1-64,
2. In removing the loading gear, secure the guide
roller with a rubber band or the like beforehand
for easier reassembly.
Remove the E ring.
Remove the relay
gear drive “@ ;
@ ©
‘e
J" Loading relay gear
Remove the E ring.
Unhook ibe slow
brake sprin
Remove the
slow brake cap. I
Remove nA
slow ved
ty
Capstan D.O. motor
Figure 1-65.
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