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2) In the test mode, perform the adjustment. After adjust-
ment is completed, cancel the test mode.
Optical
pick-up
1. Temperature compen-
X
sation offset adjustment
2. Laser power adjustment
O
3. Traverse adjustment
O
4. Focus bias adjustment
O
5. Error rate confirmation
O
3) Perform the adjustment in the order described.
4) Use the following tools and measurement equipment.
• CD test disc TGYS-1
• Laser power meter
• Oscilloscope (with bandwidth of more than 40 MΩ)
(Calibrate the probe before measurement.)
• Digital voltmeter
• Thermometer
5) Take care that VC and GND (ground) are not connected
on the oscilloscope when two or more signals are moni-
tored on the oscilloscope. (VC and GND are short-cir-
cuited in this case.)
Note : The "#" display on the screen indicates an arbitrary
figure.
3-4 Creating the recordable continuous recording
disc
This disc is used for focus bias adjustment and error rate
confirmation. How to create the recordable continuous
recording disc is described below.
1. Insert a commercial recordable disc (blank disc).
2. Turn the SHUTTLE to display "CREC MODE."
3. Press the PLAY key to display "CREC MID".
4. After pressed the PLAY key, a display indicates
"CREC(0300)" and the recording begins.
5. Terminate the recording within five minutes.
6. Press the STOP key to stop the recording.
7. Press the EJECT key to take out the recordable disc.
As a result, a continuously recorded disc can be created for
focus bias adjustment and error rate confirmation.
Note : Take care that no vibration is applied during continu-
ous recording.
3-5 Laser power adjustment
Connection :
Objective lens of
optical pick up
X33
ADJUSTMENT
TP2
TP1
7
ADJUSTMENT
BD board
IC6
D101
IC1,IC2,IC10
O
O
O
O
X
O
O
X
O
O
X
O
O
X
O
Laser
power meter
Digital
voltmeter
+
-
DM-S500
Adjustment :
1. Put the laser power meter on the objective lens of the
optical pick-up. Connect the digital voltmeter to TP1 and
TP2.
2. Turn the SHUTTLE to display "LDPWR ADJU".
(Laser power : For adjustment use)
3. Press the PLAY key to display "(0.9mW)$##".
4. Adjust to turn SHUTTLE so that the laser power meter
reads 0.86 - 0.94mW.
Set range 10mW of the laser power meter,then save to
press PLAY key.
5. "(7.0mW)$##" is displayed.
6. Adjust to turn the SHUTTLE so that laser power meter
reads 6.9-7.1mW, then save to press PLAY key.
("LDPWR<$##" is displayed momentarily.)
Don't output the laser power of 7.0mW more than 15sec.
7. Next turn the SHUTTLE to display "LDPWR CHEC".
8. Press PLAY key to display "(0.9mW)$##". Check the
laser power meter reads 0.85-0.95mW.
9. Next set range 10mW of the laser power meter, then
press PLAY key to display "(7.0mW)$##". Confirm that
the laser power meter and digital voltmeterat that time
read the specified value.
Specification :
Reading of laser power meter : 7.0 ±0.1 mW
Reading of digital voltmeter : Optical pick-up indication
value ±10%
KMS
(Optical pick-up label)
In this case, lop = 82.5 mA
lop(mA) = Reading of digital voltmeter (mV)/1(Ω)
10. Press the PLAY key to display "LDPWR CHEC" and
stop the laser emission. (The STOP key can be pressed
at any time to stop the laser emission.)
Note : The "#" display on the screen indicates an arbitrary
figure.
3-6 Traverse Adjustment
Connection :
X33
ADJUSTMENT
TE2
VC
Adjustment :
1. Connect the oscilloscope to (TE2) and (VC) on the X33
board.
2. Insert a commercial recordable disc.
3. Turn the SHUTTLE to display "EFBAL ADJU".
260A
27x40
B0825
Oscilloscope
+
-
V: 0.5V/div H: 10ms/div
INPUT: DC mode
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