20
MZ-G750/R700
2. Press the .key continuously until the optical pick-up
moves to the most inward track.
3. Open the cover and set the laser power meter on the objective
lens of the optical pick-up.
4. Press the Nkey, and set the laser MO read adjustment mode
(item number 011).
5. Check that the laser power meter reading is 0.81 ± 0.08 mW.
6. Check that the voltage both ends (TP (+) and TP (–)) of resistor
R521 at this time is below 44 mV.
7. Press the Nkey, and set the laser CD read adjustment
mode (item number 012).
8. Check that the laser power meter reading is 0.97 ± 0.10 mW.
9. Check that the voltage both ends (TP (+) and TP (–)) of resistor
R521 at this time is below 44 mV.
10. Press the Nkey, and set the laser MO write adjustment mode
(item number 013).
11. Check that the laser power meter reading is 4.95 ± 0.50 mW.
12. Check that the voltage both ends (TP (+) and TP (–)) of resistor
R521 at this time is below 80 mV.
13. Press the xkey to quit the manual mode, and activate the
test mode (display check mode).
Checking and Connection Location: MAIN board
1. Connect a digital voltmeter to the TP902 (VL) on the MAIN
board, and adjust [VOL +] key (voltage up) or [VOL --] key
(voltage down) so that the voltage becomes 2.30 ± 0.01 V.
2. When press the Xkey to write the adjusted value, LCD dis-
plays as follows and power supply manual adjustment has com-
pleted.
Adjustment and Connection Location:MAIN board
5-6. Temperature Correction
•Adjustment Method of temperature correction
1. Select the manual mode of test mode, and set the mode num-
ber 014 (see page 13).
2. Measure the ambient temperature.
3. Adjust with [VOL +], [VOL --] key so that the adjusted value
(hexadecimal value) becomes the ambient temperature.
(Initial value: 14h = 20 °C, Adjusting range: 80h to 7fh (–128
°C to +127 °C)
4. Press the Xkey to write the adjusted value.
5-7. Laser Power Check
Connection :
Checking Method :
1. Select the manual mode of test mode (see page 13), and set the
laser power adjusting mode (item number 010).
digital
voltmeter
MAIN board
TP902(VL)
TP912(GND)
This set LCD display
0 00ADJ OK
This set LCD display
0 14SetTmp: Adjusted value
digital voltmete
r
MAIN board
TP(+)
TP(–)
laser
power meter
Optical pick-up
objective lens
This set LCD display
0 10Laser
This set LCD display
0 11LrefPw: Adjusted value
This set LCD display
0 12HrefPw: Adjusted value
This set LCD display
0 13WritPw: Adjusted value