Sony CDX-646 / CDX-646X Service Manual ▷ View online
13
SECTION 4
MECHANICAL ADJUSTMENT
• Elevator Height (Address) Adjustment
Note:
This adjustments is necessary when the system controller (IC201),
variable resistor (RV201), slider (R), slider (L), or chassis (ELV)
was replaced for any repair.
variable resistor (RV201), slider (R), slider (L), or chassis (ELV)
was replaced for any repair.
Connection:
Adjustment Method:
1. Connect this set to the master unit (e.g. MDX-C7970/C7970R),
1. Connect this set to the master unit (e.g. MDX-C7970/C7970R),
load a disc magazine, and place the set vertically as shown
below.
below.
2. Connect the regulated power supply to the master unit, and
turn the power on.
3. Press the DISC button on the master unit and select DISC 5.
4. At this time, if the elevator shaft does not position between
comb teeth A and B at addresses 5 and 6 as shown below,
adjust the following.
adjust the following.
5. Press repeatedly the DISC + and – buttons on the master unit
so that the elevator shafts moves from address 6 to address 5,
or from 5 to 6. At this time, adjust RV201 on the main board
so that the elevator shaft positions smoothly between comb
teeth A and B.
or from 5 to 6. At this time, adjust RV201 on the main board
so that the elevator shaft positions smoothly between comb
teeth A and B.
6. Further, place the set horizontally and make same adjustment
as mentioned above.
7. After adjustment at addresses 5 to 6 is finished, check all op-
erations from addresses 1 to 10 with the set placed vertically
and horizontally respectively to confirm that the elevator shaft
positions in a range between comb teeth A to B.
and horizontally respectively to confirm that the elevator shaft
positions in a range between comb teeth A to B.
GND
+
BUS cable
compact disc changer
master unit
CONTROL connector
(CN901)
(CN901)
power supply
(DC 14.4 V)
RV201
comb tooth at address 6
elevator shaft
comb tooth at address 6
comb tooth at address 5
OK
NG
elevator shaft
comb tooth at address 5
A
B
A
B
14
SECTION 5
ELECTRICAL CHECK
Note:
1. This check is performed with the set placed horizontally.
2. Power supply voltage: DC14.4 V (more than 3 A).
3. Be sure to use the disc “YEDS-18” parts code: 3-702-101-01, but only
2. Power supply voltage: DC14.4 V (more than 3 A).
3. Be sure to use the disc “YEDS-18” parts code: 3-702-101-01, but only
when indicated.
Connection:
Focus Bias Check
Connection:
– RF Board (Component Side) –
Procedure:
1. Connect the oscilloscope to TP (RFO) and TP (VC) on the RF
1. Connect the oscilloscope to TP (RFO) and TP (VC) on the RF
board.
2. Put the set into play mode by loading the disc (YEDS-18).
3. Confirm that oscilloscope waveform is clear and check RF sig-
3. Confirm that oscilloscope waveform is clear and check RF sig-
nal level is correct or not.
Note:
Clear RF signal waveform means that the shape “
◊
” can be clearly distin-
guished at the center of the waveform.
When observing the eye pattern, set the oscilloscope to AC range
and raise the vertical sensitivity so that it may be easily seen.
and raise the vertical sensitivity so that it may be easily seen.
GND
+
BUS cable
compact disc changer
master unit
CONTROL connector
(CN901)
(CN901)
power supply
(DC 14.4 V)
oscilloscope
(AC range)
+
–
–
TP (VC)
TP
(RFO)
IC101
RF signal waveform
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
(10 : 1 probe in use)
TIME/DIV: 500 ns
(10 : 1 probe in use)
level: 1.4
±
0.3 Vp-p
15
Tracking Offset Check
Connection:
– RF Board (Component Side) –
Procedure:
1. Connect the oscilloscope to TP (TE) and TP (VC) on the RF
1. Connect the oscilloscope to TP (TE) and TP (VC) on the RF
board.
2. Put the set into play mode by loading the disc (YEDS-18).
3. Press the . , > buttons on the master unit, and check the
3. Press the . , > buttons on the master unit, and check the
traverse waveform*.
4. Confirm that the oscilloscope waveform is symmetrical on the
top and bottom in relation to 0 V dc, and check this level.
* Traverse waveform: This is the tracking error wave form appears
when crossing the track.
oscilloscope
(DC range)
+
–
–
TP (VC)
TP (TE)
IC101
A
B
0 V
A=B
traverse waveform
(100 track jump waveform)
(100 track jump waveform)
VOLT/DIV: 500 mV
TIME/DIV: 2 ms
Center: 0 V
TIME/DIV: 2 ms
Center: 0 V
Traverse waveform
17
17
CDX-646/646X
M
M
6
7
VO4+
VO4–
VIN4+
VIN4–
10
11
VO2+
VO2–
MOTOR
DRIVE
MOTOR
DRIVE
COIL
DRIVE
12
13
VO1+
VO1–
VIN2+
VIN2–
42
43
FFDR
FRDR
38
39
31
32
22
21
5
4
VL0+
VL0–
FWD
REV
1
2
SFDR
SRDR
A
B
C
D
E
F
I-V AMP
PD
LD
DETECTOR
5
6
7
8
11
10
E I-V AMP
F I-V AMP
E
D
C
B
A
F
3
LD
RF
SUMMING
AMP
FOCUS
ERROR
AMP
RF EQ
AMP
16
RFO
14
FE
13
4
TE
TRACKING
ERROR
AMP
AUTOMATIC
POWER
CONTROL
Q101
APC LD
AMP
PD
AGC
22
21
20
LDON
HOLD SW
AGCCONT
APC PD
AMP
LDON
HOLD
AGC
RFDC
FE
TE
54 50 52 51
RFDC
FE
TE
61
60
59
ASYMMENTRY
CORRECTOR
RFAC
ASYI
ASYO
ASYO
DIGITAL
PLL
EFM
DE-
MODULATOR
D/A
INTER-
FACE
63 66 65
64
FILO
CLTV
PCO
FILI
83
EMPH
FILTER
INTERNAL BUS
77
81
79
78
82
80
PCMD
LRCK
BCK
32k RAM
ERROR
CORRECTOR
54
55
56
LDON
HOLD
AGC
LDON
AGCHOLD
RF AGC
91 GFS
22
GFS
6
CDDATA
13
DATA
7
CDCLK
15
CLOK
5
CDXLT
77 SQSO
79 SQCK
82 SCOR
92 SCLK
90 FOK
XRST
14
XLAT
93 SENS
16
SENS
6
SQSO
7
SQCK
24
SCOR
17
SCLK
32
FOK
CPU
INTERFACE
SUBCODE
PROCESS
PROCESS
RFDC
FE
TE
SE
OP AMP
ANALOG SWITCH
A/D CONVERTER
MIRR
DFCT
FOK
DIGITAL SERVO
SIGNAL PROCESS
PWM GENERATOR
40
41
25
24
TEDR
TRDR
VIN1–B
18
8
9
VO3+
VO3–
VIN3+
VIN3–
DIGITAL
CLV
35
MDP
M
M103
(CHUCKING)
M102
(SPINDLE)
M101
(SLED)
TRACKING/FOCUS COIL DRIVE,
SLED/SPINDLE/CHUCKING
MOTOR DRIVE
IC201
MOTOR
DRIVE
COIL
DRIVE
SERVO AUTO
SEQUENCER
SERVO
INTERFACE
94
CH. F
71
CH. R
72
89
11
XRST
36
SSTP
LIMSW
SW3
(LIMIT)
65 LOAD1
SW2
(SAVE END DETECT)
66 LOAD2
SW1
(CHUCKING END DETECT)
ON : When the optical pick-up
is inner position
is inner position
ON : When completion of the disc
save operation
save operation
ON : When completion of the disc
chucking operation
chucking operation
84
SERIAL
IN
INTERFACE
DIGITAL FILTER,
NOISE SHAPER
97
90
96
91
AOUT2
AOUT1
BUFFER
AIN2
AIN1
92
95
LOUT1
LOUT2
GND-ISOLATION
IC401
EMPHI
PCMDI
LRCKI
BCKI
L
R
MUTING
Q410, 420
87
XTAO
86
XTAI
X130
16.9344MHz
TIMING
LOGIC
CLOCK
GENERATOR
4
AMUTE
SYSTEM CONTROLLER
IC201 (1/2)
DIGITAL SIGNAL PROCESSOR,
DIGITAL FILTER, D/A CONVERTER,
DIGITAL SERVO PROCESSOR
IC101
(TRACKING)
(FOCUS)
2-AXIS DEVICE
OPTICAL
PICK-UP BLOCK
(KSS-720A)
05
RF AMP,
FOCUS/TRACKING ERROR AMP
IC101
• SIGNAL PATH
: CD PLAY
LASER DIODE
PWM
&
INTEGRATOR
ANALOG OUT
L
R
CN901 (1/2)
MUTING
CONTROL
Q403
SECTION 6
DIAGRAMS
6-1.
BLOCK DIAGRAM – MAIN Section –
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