MD-M3/M1
– 22 –
Figure 22-3 Optical Pickup Grating Deviation
Measuring Method
Mechanism Adjustment
1. Optical pickup grating inspecting method
After the automatic adjustment has been performed in the AUTO
mode (test mode) using the low reflection test disk MMD212 (TEAC)
("COMPLETE" will have been displayed), adjust the Lissajous
waveform (x-y) using EOUT and FOUT.
1. Slightly loosen the 3 screws of spindle motor, and make an
adjustment, observing the Lissajous's waveform.
2. After the adjustments are complete, tighten the screws in numerical
order: 1 , 2 and then 3 . (See Fig. 22-4.)
Lead-in switch position measurement mode
Insert High reflection test disk (TGYS1)
Note: Adjust the lead-in switch position to FF85 to FFDF.
1. Loosen the screw (A) x 2 pcs. which fix the mechanism switch
PWB.
2. Retighten the screw, pressing the mechanism switch PWB in
the arrow direction, and then measure the lead-in switch
position again.
After position adjustment fix with the two screws (A). (See Fig. 22-1.)
Note: After tightening the two screws on the PWB apply Screw Lock.
Figure 22-1
Forced rotation of loading motor
When STOP or EJECT appears in the display and the VOLUME
CONTROL knob is rotated (up or down), it allows the loading motor
to be forced to run (loading and unloading operations).
Figure 22-2
Figure 22-4
Adjustment of magnetic head mounting position
When the magnetic head and optical pickup have been replaced, be
sure to adjust the mounting position.
For easier adjustment of mounting position move the optical pickup
to the center position, and then adjust the position.
1. Set the adjusting transparent disc 3.
2. Lower the magnetic head up-shift arm with your finger, and raise
the magnetic head.
3. Viewing the set from above, make an adjustment so that the
magnetic head aligns with the optical pickup objective lens.
4. Make sure that there is a clearance as shown in Figure 22-2 and
the magnetic head moves up and down smoothly.
Loosen the
two screws (A).
Lead In Switch
Mechanism Switch PWB
Magnetic head
Magnetic head
Push
Tangential direction
Objective lens
Radial direction
1
2
3
1
2
3
adjusting
hole
Spindle motor
Check the Lissajou's waveform,
shifting the mounting position with
a screwdriver (to be fitted into the
disc motor adjusting hole).
Spindle Motor
Adjusting hole
GND CH1
CH2
X
Y
GND (TP1125)
43 Pin of IC1101
26 Pin of IC1101
25 Pin of IC1101
EOUT (TP1129)
FOUT (TP1130)
100K
OSILLOSCOPE
470p
470p
a
b
Less than a:b = 4:1
LISSAJOUS'S WAVEFORM
100K
Содержание CP-M1
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