Tape Adjustments - Sanyo DC-DA70 Service Manual

CD PLAYER ADJUSTMENTS
(2) Checking the "eye" pattern
1. Switch "ON" the POWER.
2. Connect an oscilloscope to TP1 (RF) and TP4 (VC).
3. Load the test disc.
4. Press the PLAY button.
5. Check to be sure that the "eye" pattern is at the center of
waveform and that the diamond shape is clearly defined.
6. Press the STOP button.
7. Turn off the POWER switch.

TAPE ADJUSTMENTS

a. Replacing the head
1. After replacement, demagnetize the heads by using a
degausser.
2. Be sure to clean the heads before attempting to make any
adjustments.
3. Be sure both channels (1 and 2) are the same level.
(Using a dual-channels oscilloscope).
4. All wiring should be returned to the original position after
work is completed.
b. Adjusting head azimuth
1. Load a test tape (VTT-738, etc. :10kHz) for azimuth
adjustment.
2. Press the PLAY button.
3. Use a cross-tip screwdriver to turn the screw for normal
azimuth adjustment so that the left and right outputs are
maximized at the same phase during normal playback.
4. Press the STOP button.
c. Adjusting motor speed
d. Replacing the motor
R / P HEAD
RED WHITE
YELLOW EARTH
e. Checking the mechanism torques
- 2 -
+
TP1
(RF)
-
TP4
(VC)
a
1. Insert the test tape (MTT-111 or etc. 3,000 Hz).
2. Press the PLAY button.
3. Use a flat-tip screwdriver to turn the SVR to adjust so that
the frequency counter becomes 3,000 Hz.
4. Press the STOP button.
MOTOR SPEED
ADJUSTMENT
1
4
• Clean the head, capstan and pinch roller before making any
measurement.
Measureent Take-up torque
Cassette for PLAY : TW-2111A
measurement F.FWD/REW : TW-2231
PLAY 30 ~ 70gr.cm
F.FWD/REW 55 gr or more
OSCILLOSCOPE
OPENING EXPANDED
b
3
2
4
Back tension Tape tension
PLAY : TW-2111A Drive-power cassette
TW-2412
1.0 ~ 6.0gr.cm 80 gr or more
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