Sony Walkman MZ-R900 Service Manual page 19

2. When press the key to write the adjusted value, LCD dis-
X
plays as follows and power supply manual adjustment has com-
pleted.
Remote commander LCD display
000
Adjustment and Connection Location: MAIN board
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).
Remote commander LCD display
014
: Adjusted value
2. Measure the ambient temperature.
[VOL +] [VOL --]
3. Adjust with ,
(hexadecimal value) becomes the ambient temperature.
(Initial value: 14h = 20 C, Adjusting range: 80h to 7fh (–128
C to +127 C)
4. Press the key to write the adjusted value.
X
Laser Power Check
Connection :
Optical pick-up
objective lens
MAIN board
TP (+)
TP (–)
Checking Method :
1. Select the manual mode of test mode (see page 13), and set the
laser power adjusting mode (item number 010).
Remote commander LCD display
010
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 N key, and set the laser MO read adjustment mode
(item number 011).
Remote commander LCD display
011
5. Check that the laser power meter reading is 0.81
6. Check that the voltage both ends (TP (+) and TP (–)) of resistor
R521 at this time is below 44 mV.
key so that the adjusted value
laser
power meter
digital voltmeter
0.08 mW.
7. Press the key, and set the laser CD read adjustment
N
mode (item number 012).
Remote commander LCD display
012
8. Check that the laser power meter reading is 0.97
9. Check that the voltage both ends (TP (+) and TP (–)) of resistor
R521 at this time is below 44 mV.
10. Press the key, and set the laser MO write adjustment mode
N
(item number 013).
Remote commander LCD display
013
11. Check that the laser power meter reading is 4.95
12. Check that the voltage both ends (TP (+) and TP (–)) of resistor
R521 at this time is below 80 mV.
13. Press the x key to quit the manual mode, and activate the
test mode (display check mode).
Checking and Connection Location: MAIN board
Adjustment/checking and Connection Location:
– MAIN Board (Conductor side) –
AP912
(GND)
R317
C211
C118
C112
C117
4 1
R118
C212
5 16
IC303
28
8 13
9 12
1
IC301
R102
R101
7
8
C217
C306
C218
C302
C304
R319
L301
L302
C327 + C345
R916
+ C904
C344
C927
D303
K A
R310 14
D903
15
4 1
C906
R941
5 16
R909
IC302
8 13
R815
C908 C921
IC901
9 12
C905
R902
C331
FB301
K A
28
FB302 D904
FB303 29
D901
C337
FB304
A K
C
FB305 C333
Q803
C324 C901 +
D301
FB306
B E
C317
K
D302 C338
A
C335
C329
C106
R204
R203
R104
R205
Q801
R105
C836 C107 R846
C601
1 5 10 15 18
CN801
DC IN 3V
–
MZ-R900
0.10 mW.
0.50 mW.
AP914
(VC)
AP915
(VL)
CN502
15 10
R305
42
22 R304
43
21
IC551
4 3
15
14
IC902
1 2
+ 56
C301
1
C521
Q904
R501
+
C529 R502
R920
1 C926
56
R919
L501
R914
C526
R918
R917
TP (–)
TP (+)
43
42
+
C919
R949
R912
+
C920
R901
R946
R948 Q903
R936 R913
B C E
TH601
D605
A K
R622
A K
D602
C837
J601
+
5 1
29
28
C
15
14
R507
C503
C505
C506
C507
19