Aiwa CSD-MD50, Service Manual, Page: 35 / 74

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2-8. Checking Servo Operation
• Checking the focus search and spindle kick: 1
1) When the MD
2
button is pressed while the machine is in the “ALL SV OFF” status without inserting a disc, focus search
and spindle kick are performed continuously.
The message “FOCUS SRCH” appears on the display.
2) After the check is completed, press the
9
button to show the message “ALL SV OFF” on the display.
• Checking the focus search and spindle kick: 2
1) When the “TUNER/BAND” button is pressed while the machine is in the “ALL SV OFF” status with a disk inserted or
without inserted, focus search and spindle kick are performed continuously .
The message “FOCUS CHECK” appears on the display.
The S curve characteristics can be checked when a disc is inserted.
2) After the check is completed, press the
9
button to show the message “ALL SV OFF” on the display.
• Checking the focus servo
1) Insert a test disc.
2) Move the laser pickup to the center of a disc using the
6
button and
5
button.
3) Press the TAPE
1 2
button, and set the servo mode of the inserted disc as follows.
MO disk (MO) ................................... Select the “SELECT GRV” display.
PIT disk (CD) .................................... Select the “SELECT PIT” display.
4) Press the MD
2
button.
When the focus servo has no problem, the messages “FOCUS SRCH” appears then “FOCUS ON!” appears on the display.
5) After the check is completed, press the
9
button to show the message “ALL SV OFF” on display.
• Checking that all servos are turned ON
1) When the “ENTER” button is pressed while the machine is in the “FOCUS ON!” status, the tracking and sled servos are
turned on and all servos start moving.
When the all servos have no problem, the message “ALL SV ON” appears on the display.
2) After the check is completed, press the
9
button to show the message “ALL SV OFF” on display.
3. ADJUSTMENT (MD)
3-1. Temperature Compensation Adjustment
Test point: Adjustment result is shown on the display
Jig: Thermometer
Adjustment method:
1) After activating the MD TEST mode, press the
9
button to display the “ALL SV OFF” .
2) Press the “DISP” button to change the display to “TEMP=$
⁄⁄
”.
3) Press the “EDIT” button to change the display into “TMP+**c:±## ”.
4) Place a thermometer near MD mechanism to measure the room temperature.
5) Perform adjustment by pressing the
6
and
5
buttons until the thermometer reading and the value ** that is shown on the
display agree. Press the “ENTER” button.
6) After the adjustment is completed, press the
9
button to display “ALL SV OFF”.
7) When the setting is completed, display the “TMP+**c:+##” again and check the value that is calculated by adding or
subtracting the ## value to and from ** must be the room temperature.
Note: Don’t perform the above adjustment if the room temperature cannot be measured.
3-2. Laser Power Adjustment
Test point: Pick up laser output
Jig: Laser power meter
Adjustment method:
1) Press the “TIMER/CLOCK” button three times in the “ALL SV OFF” state to change the display to “LASER WRITE”.
2) Press the “EDIT” button once to display “LASER=$**”.
3) Measure the pick up laser output using the laser power meter, and perform adjustment so that the measuring value is 6.8±
0.03mW by pressing the
6
and
5
buttons. After the adjustment is completed, press the “ENTER”button.
4) Press the
9
button to display “ALL SV OFF”.
Note:
If laser output exceeds 7.0mW, the pick up may be damaged.