JVC KD-SX950 User manual

SERVICE MANUAL
CD RECEIVER
No.49539
Feb. 2000
COPYRIGHT 2000 VICTOR COMPANY OF JAPAN, LTD.
This service manual is made from 100% redycled paper.
Printed in Japan
200002(V)
VICTOR COMPANY OF JAPAN, LIMITED
MOBILE ELECTRONICS DIVISION,10-1,1Chome,Ohwatari-machi,maebashi-city,Japan
KD-SX950
(No.49539)
KD-SX950
KD-SX950
Area Suffix
J ---- Northerm America
Contents
Safety precaution  1-2
Instructions 1-3~16
Disassembly method 2-1
Adjustment method 2-6
Flow of functional operation
until TOC read  2-7
Maintenance of laser pickup 2-9
Description of major ICs 2-10
Block diagram  2-26
Standard schematic diagrams 2-27
Printed circuit boards 2-29~31
Parts list 3-1~
CD
DISP
SCM
RPT
SSM
BBE
MO
RND
789
CD CHANGER CONTROL
10 11 12
INT
CD -CH
FM/AM
/I
ATT
/
SCAN
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!CAUTION Burrs formed during molding may be left over on some parts of the chassis. Therefore,
pay attention to such burrs in the case of preforming repair of this system.
Safety precaution
!CAUTION Please use enough caution not to see the beam directly or touch it in case of an
adjustment or operation check.
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Disasembly method
Removing the front panel unit
1.Press the Eject button to open the front panel unit
(See fig 1)
2.Push and open the right and left open/close shaft arms
outward to remove the shaft.(See fig 2)
3.Remove the front panel unit from the same side as the
shaft was removed.
1.Remove the front panel unit.
2.Remove the two screwsAbsecuring the front chassis
assembly.(See fig 3)
3.Remove the four ribsaasecuring the front chassis
assembly to the chassis.(See fig 4)
Removing the front chassis assembly
Removing the bottom cover assembly
Turn the unit upside down,then insert and turn to
b the screwdriver to remove the bottom cover.
(See fig 5)
Fig 5
Fig 1
Eject button
Front panel unit
Fig 2
Open/close
shaft arm
Fig 3 A
a
Fig 4 a
b
bb
b
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1.Remove three screws Eretaining the rear panel to the
chassis
2.Remove one screw Cretaining the IC to the heat sink.
3.Remove two screws Dretaining the main bord.
4.Lift up the main board to remove it.
5.Remove two screws Bto remove the heat sink.
Removing the rear brackt (See fig7)
1.Remove one screw I to remove the IC bracket.
2.Remove one screw Fto remove the line-out jack.
3.Remove one screw G to remove the antenna jack.
4.Remove one screw Hto remove the connector.
5.Remove one screw Lto remove the connector.
CD mechanism assembly (See fig8)
Remove three mechanism mounting screws Jretaining the
top cover.
Front panel unit (See fig9)
Remove five screws Kretaining the rear cover.
Removing the main board(wiht rear panel)
(See fig6.7)
Fig 9
Fig 8
J
JJ
B
B
C
Fig 6
KK
KKK
E
G
Fig 7
E
EI
LLHF
DD
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Unsolder the part f and g on the CD mechanism
control board.
Remove the stator fixing the CD mechanism control
board and the damper bracket (To remove the stator
smoothly, pick up the center part).
Remove the screw F attaching the CD mechanism
control board.
Remove the CD mechanism control board in the
direction of the arrow while releasing it from the two
damper bracket slots i and the front bracket slot j.
Disconnect the flexible wire from connector on the
pickup unit.
Removing the CD mechanism control
board(See Fig.1 and 2)
Turn the FD gear in the direction of the
arrow to move the entire pickup unit to
the appropriate position where the
flexible wire of the CD mechanism unit
can be disconnected easily (Refer to
Fig.2).
ATTENTION:
Fig.1
Fig.2
Fig.3
Fig.4
Front bracket
CD mechanism
control board
Shift the lock
Flexible wire
Pickup unit
FD gear
CD mechanism control board
Loading motor Front bracket
Front bracket Pull outward
Pull outward
Flame
Damper bracket
mm
h
i
g
f
II
I
CD mechanism ass’y
Fj
k
G
k
G
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Prior to performing the following procedure, remove
the CD mechanism control board.
Remove the two springs k attaching the CD mechanism
ass’y and the front bracket.
Remove the two screws G and the front bracket
while pulling the flame outward.
Remove the belt and the screw H from the loading
motor.
*
1.
2.
3.
Removing the loading motor
(See Fig.3 to 5)
Prior to performing the following procedure, remove
the CD mechanism control PWB and the front
bracket (loading motor).
Remove the three screws I and the damper bracket.
Raise the both sides fix arms and move the fix plates
in the direction of the arrow to place the four shafts l
as shown in Fig.8 and 9.
Remove the CD mechanism ass’y and the two
springs m attaching the flame.
Remove the two screws J and both sides rear
damper brackets from the dampers. Detach the CD
mechanism ass’y from the left side to the right side.
*
1.
2.
3.
4.
Removing the CD mechanism ass’y
(See Fig.1, 6 to 9)
The CD mechanism ass’y can be
removed if only the rear damper
bracket on the left side is removed.
ATTENTION:
Fig.5
Fig.6
Fig.7
Fig.8
Fig.9
Rear damper bracket
Fix arm (R)
Damper
H
II
Loading motor
Belt
Damper bracket
CD mechanism ass’y
Flame
m
m
I
I
Fix plate (L)
l
l
Rear damper bracket
Fix arm (L)
Damper
J
Fix plate(R)
J
l
l
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Prior to performing the following procedure, remove
the CD mechanism control board, the front bracket
(loading motor) and the CD mechanism ass’y.
Remove the two screws K and the feed motor ass’y.
*
1.
Removing the feed motor ass’y
(See Fig.10)
*Prior to performing the following procedure, remove
the CD mechanism control board, the front bracket
(loading motor), the CD mechanism ass’y and the
feed motor ass’y.
Detach the FD gear part of the pickup unit upward.
Then remove the pickup unit while pulling out the
part n of the FD screw.
*
1.
Remove the screw L attaching the nut push spring
plate and the pickup mount nut from the pickup unit.
Pull out the FD screw.
2.
Removing the pickup unit
(See Fig.10 and 11)
When reattaching the pickuap unit,
reattach the part o of the pickup unit,
then the part n of the FD screw.
ATTENTION:
Prior to performing the following procedure, remove
the CD mechanism control board, the front bracket
(loading motor), the CD mechanism ass’y and the
feed motor ass’y.
Turn up the CD mechanism ass’y and remove the
two springs p on both sides of the clamper arms.
Open the clamper arm upward.
Turn the turn table, and remove the two screws M
and the spindle motor.
*
1.
2.
Removing the spindle motor
(See Fig.12 and 13)
Fig.10
Fig.11
Fig.12
Fig.13
Spindle motor
pp
Pickup unit
Part n
FD screw
Feed motor ass’y
FD gear Pickup unit
Part O
K
Nut push spring plate
Pickup mount nut
Pickup unit
FD screw
L
M
M
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Adjustment method
Test instruments required for adjustment
1. Digital oscilloscope (100MHz)
2. AM Standard signal generator
3. FM Standard signal generator
4. Stereo modulator
5. Electric voltmeter
6. Digital tester
7. Tracking offset meter
8. Test Disc JVC :CTS-1000
9. Extension cable for check
EXTGS004-26P 1
Standard measuring conditions
Power supply voltage DC14.4V(10.5~16V)
Load impedance 20Kohm(2 Speakers connection)
Output Level Line out 2.0V (Vol. MAX)
How to connect the extension cable for adjusting
Dummy load
Exclusive dummy load should be used for AM,and FM. For
FM dummy load,there is a loss of 6dB between SSG output
and antenna input.The loss of 6dB need not be considered
since direct reading of figures are applied in this working
standard.
Standard volume position
Balance and Bass &Treble volume : lndication"0"
Loudness : OFF
BBE : OFF
Frequency Band
FM 87.5MHz ~ 108.0MHz
MW 522kHz ~ 1620 kHz
LW 144kHz ~ 279kHz
EXTGS004-26P
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Power ON
 Set Function to CD
Play
Jump to the first track
TOC readout
Tracking loop closed
Disc rotates
Disc inserted
YES
YES
Laser emitted
Pickup feed to the inner area
Focus search
RF signal eye-pattern
opens
RF signal eye-pattern
remains closed
"No disc"
display
• When correctly focused
 Focus Servo Loop ON
• When the laser diode correctly
emits
Microprocessor
commands
Rough Servo Mode
CLV Servo Mode
(ProgramArea)
CLV Servo Mode
(Lead-In Area;
Digital: 0)
• RF signal
Flow of functional operation until TOC read
• When the pickup correctly moves
to the inner area of the disc
TERMINAL
Microprocessor
commands
FMO
TC9462 "53"
FEED MOTOR
+TERMINAL
IC581 "5"
REST SW
• When the disc correctly rotates
Tracking Servo Loop ON
Servo CLV
Rough
Servo
AccelerationAcceleration
Microprocessor
commands
Spindle
motor (-)
IC581 "7"
0.5 Sec 0.5 Sec
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Feed Section
Focus Section
Tracking Section
Spindle Section
Is the voltage output at
IC521 pin "53" 5V or 0V?
Check the feed motor.
Is 4V present at both
sides of the feed motor?
Is the wiring for IC521
(90) ~ (100) correct?
Check IC581.
Is 6V or 2V present at
IC581 "5" and "6"?
Is 5V present at IC581
pin "11"?
Check the feed motor
connection wiring.
Check the vicinity of
IC521.
Check CD 9V
and 5V.
YES
YES
YES
NONO
NO
NO
NO
YES
YES
When the lens is
moving:
Check the circuits in
the vicinity of IC581
pins "15" ~ "18".
Check the pickup and
its connections.
NO
YES
YES
YES
Does the S-search
waveform appear at
IC581 pins "17" and "18"?
Is the disk rotated?
Does the RF signal
appear at TP1?
Is 4V present at IC581
pins "7" and "8" ?
Check the spindle motor
and its wiring.
Is 4V present at IC521
pin "55" ?
Check the vicinity of
IC581.
Check IC501 and
IC521.
YES
NO
NO
NO
NO NO
YES
YES
YES
Check the circuits in the
vicinity of IC501 "19" ~
"24" or the pickup
Is the RF waveform at TP1
distorted?
Proceed to the Tracking
section
When the disc is rotated
at first:
Check the circuit in the
vicinity of IC501 pins
"2" ~ "12".
Check IC521.
Check the pickup and
its connections.
YESYES
YES
Is the tracking error signal
output at IC501 "12"?
Approx. 1.2 V
4V
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Maintenance of laser pickup
(1) Cleaning the pick up lens
Before you replace the pick up, please try to
clean the lens with a alcohol soaked cotton
swab.
(2) Life of the laser diode
When the life of the laser diode has expired,
the following symptoms will appear.
(1) The level of RF output (EFM output:ampli
tude of eye pattern) will be low.
Replacement of laser pickup
Is RF output
1.0 0.35Vp-p? Replace it.
NO
YES
O.K
(3) Semi-fixed resistor on the APC PC board
The semi-fixed resistor on the APC printed
circuit board which is attached to the pickup
is used to adjust the laser power.Since this
adjustment should be performed to match the
characteristics of the whole optical block,
do not touch the semi-fixed resistor.
If the laser power is lower than the specified
value,the laser diode is almost worn out, and
the laser pickup should be replaced.
If the semi-fixed resistor is adjusted while
the pickup is functioning normally,the laser
pickup may be damaged due to excessive current.
Turn off the power switch and,disconnect the
power cord from the ac outlet.
Replace the pickup with a normal one.(Refer
to "Pickup Removal" on the previous page)
Plug the power cord in,and turn the power on.
At this time,check that the laser emits for
about 3seconds and the objective lens moves
up and down.
Note: Do not observe the laser beam directly.
Play a disc.
Check the eye-pattern at TP1.
Finish.
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1314
CL- LGND OUTL OUTR RGND CR - CR +
CL+ Vcc INL NFL FIL NFR INR
1112 9 810
21 43 6 75
REFL REFR
FILTER
BA3220FV-X (IC301,IC401) : Driver
1. Pin layout & Block diagram
2. Pin functions
1
2
3
4
5
6
7
8
9
10
11
12
13
14
CL+
Vcc
INL
NFL
FIL
NFR
INR
CR+
CR-
RGND
OUTR
OUTL
LGND
CL-
Powe supply terminal for amp.
power supply terminal.
input terminal.
Negative feedback terminal.
Filter terminal.
Negative feedback terminal.
Input terminal
Power supply terminal for amp.
Output terminal of internal amp.
Rch GND terminal.
Rch output terminal.
Lch output terminal.
Lch GND terminal.
Output terminal of internal amp.
Pin
No. Symbol Function
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1 2 3 4 5 6 7 8 9 10 11 12
BA4905-V3 (IC961) : Regulator
1.Terminal layout
2.Block daigram
EXT
EXT ACC AUDIO 9V CTRL ILM 10V GND
RESET
RESET COMP VDD 5.7V CD 8V VCC AJ
1 2 3 4 5 6 7 8 9 10 11 12
37K
5K
REGULATOR
Overvoltage protection circuit
Pin no. Symbol Function
RESET
EXT output
COMP output
ACC
VDD output
AUDIO output
CD output
CTRL
VCC
ILM output
AJ
GND
1
2
3
4
5
6
7
8
9
10
11
12
If VDD voltage becomes 4V or less.RESET output becomes low level.
This output voltage is approximately 0.5V lower than VCC. and max
output current is 300mA.
A voltage supply for ACC block. This output voltage is approximately
0.7V lower than VDD'S. The max output current is 100mA.
Control of the COMP output by inputting voltage.
This output voltage is 5.7V, and max output current is 100mA.
This voltage supply is for microcomputer. Whenever back up voltage
supply is connected, the output keeps on running.
This output voltage is 9.0v, and max output current is 500mA.
This voltage supply for AUDIO.
This output voltage is 8.0V, and max output current is 1A.
This voltage supply for CD.
Output selector of CD. AUDIO, ILM and EXT.
To be connected with the BACK UP of car.
This output voltage is 10V, and max output current is 500mA.
Output voltage is adjustable.
Putting a resistance between ILM and AJ or between AJ and GND
makes ILM output voltage adjustable.
Ground.
3.Pin function
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BD3860K (IC911) : E. volume
1. Pin layout
2. Block diagram
3. Pin function
1 ~ 11
33 ~ 23
34
44
~
22
12
~
13
12
7
8
10
11
41
42
43
44
1
2
3
4
6 5 9 40 36 35 34 33 28 32 31 30 29 19 15 14
39 38 37 25 24 26 23 22 21 20 18 17 16
GND FIL VCC SEL1
0 to 18 dB
0 to 18 dB
VIN1 LOUD1 HF1 LF1 DET1 TIN1 TNF1 BNF1
OUTF1
OUTR1
SI
SC
OUTR2
OUTF2
BOUT2BNF2TNF2TIN2BBOUT2MIX2VCA2DET2LF2HF2LOUD2VIN2SEL2
D2
C2
B2
A2
D1
C1
B1
A1
BOUT1VCA1 MIX1 BBOUT1
POWER
SUPPLY INPUT
GAIN
INPUT
GAIN
MAIN
VOLUME
0 to -40 dB
LOUDNESS
MAIN
VOLUME
0 to -40 dB
LOUDNESS
LOW(f=50Hz) 6dB
PROCESS CONTROL +3 to 12dB
(f=10kHz)
LOW(f=50Hz) 6dB
PROCESS CONTROL +3 to 12dB
(f=10kHz)
TREBLE
-14 to +14dB
TREBLE
-14 to +14dB
BASS
-14 to +14dB
BASS
-14 to +14dB
FADER
CH1 FRONT
0 to -5 dB
FADER
CH2 FRONT
0 to -5 dB
FADER
CH1 REAR
0 to -5 dB
FADER
CH2 REAR
0 to -5 dB
LOGIC
INPUT
SELECTOR
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
CH2 input terminal A
CH2 input terminal B
CH2 input terminal C
CH2 input terminal D
1/2 VCC terminal
Ground terminal
Serial data input terminal
Serial clock input terminal
Power supply
CH2 rear output terminal
CH2 front output terminal
CH1 rear output terminal
CH1 front output terminal
CH1 bus filter setting terminal
CH1 bus filter setting terminal
CH2 bus filter setting terminal
CH2 bus filter setting terminal
CH2 treble filter setting terminal
CH1 treble setting terminal
CH2 treble input terminal
CH2 BBE II signal output terminal
CH2 output mix amp negative input terminal
A2
B2
C2
D2
FIL
GND
SI
SC
VCC
OUTR2
OUTF2
OUTR1
OUTF1
BOUT1
BNF1
BOUT2
BNF2
TNF2
TNF1
TIN2
BBOUT2
MIX2
Pin
No. Symbol Function
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
CH2 high frequency VCA output terminal
CH2 low frequency filter setting terminal
CH2 high frequency filter setting terminal
CH2 high frequency attack release time setting
Non connect
CH1 high frequency attack release time setting
CH1 treble input terminal
CH1 BBE II signal output terminal
CH1 output mix amp. negative input terminal
CH1 high frequency VCA output terminal
CH1 low frequency filter setting terminal
CH1 high frequency filter setting terminal
CH1 loudness filter setting terminal
CH1 main volume input terminal
CH2 loudness filter setting terminal
CH2 main volume input terminal
CH2 input gain output terminal
CH1 input gain output terminal
CH1 input terminal A
CH1 input terminal B
CH1 input terminal C
CH1 input terminal D
VCA2
LF2
HF2
DET2
NC
DET1
TIN1
BBOUT1
MIX1
VCA1
LF1
HF1
LOUD1
VIN1
LOUD2
VIN2
SEL2
SEL1
A1
B1
C1
D1
Pin
No. Symbol Function
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BU4066BCF-X (IC153) : Switch
14 13 12 11 10 9 8
1 2 3 4 5 6 7
I/O 1 O/I 1 O/I 2 I/O 2
C2 C3
VSS
VDD C1 C4 I/O 4 O/I 4 O/I 3 I/O 3
14 13 12 11 10 9 8
1 2 3 4 5 6 7
2.Block Diagram
1.Terminal Layout
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Vcc Vcc
Input
See Function Table
1A
2A
3A
4A
1C
2C
3C
4C
1Y
2Y
2Y
3Y
4Y
Output
Output
Output
Output
Sample as Load Circuit 1
Sample as Load Circuit 1
Sample as Load Circuit 1
1k
1k
S1
CL
Inputs Outputs
C
L
H
H
A
X
L
H
Y
Z
H
L
1
2
3
4
5
6
7
14
13
12
11
10
9
8
HD74HC126FP-X (IC771) : Buffer
1. Pin layout
3. Block diagram
2. Function
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IN
Vout
OUT
1
3
2
OP1
Co1
IC-PST600M/G/-W (IC702) : System reset
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11
1
12
4
10
15
25
13
14
16 24
23
21
18
19
17
22
2
3
5
8
7
9
206
+
-
-
+
+
-
-
+
+
-
+
-
+
-
+
-
IN 1
TAB
IN 2
ST BY
R.F
IN 3
N.C
PRE GND
IN 4
ON TIME PWR GND4
OUT 4-
OUT 4+
PWR GND3
OUT 3-
OUT 3+
MUTE
PWR GND2
OUT 2-
OUT 2+
PWR GND1
OUT 1-
OUT 1+
VCC3/4
VCC1/2
LA4743B (IC351) :Power amp
Muting &
on time control
circuit
Protective
circuit
Mute
circuit
Ripple
filter
Stand by
switch
Protective
circuit
12345678910 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
TAB GND1 OUTFR+ STBY OUTFR- VCC1/2 OUTRR+ GND2 OUTRR- VREF INRR INFR SGND INFR
INRL ONTIME OUTRL+ GND3 OUTRL- VCC3/4 OUTFL+ MUTE OUTFL- GND4 NC
1.Terminal layout
2.Block diagram
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~
~
1 14
28 15
LA6557-X(IC581):Driver
1.Terminal layout
2.Block diagram
VCC2 1
2
3
4
5
6
7
8
9
10
11
12
13
14
V05-
V05+
V04+
V04-
V03+
V03-
FR FR
28
27
26
25
24
23
22
21
20
19
18
17
16
15
FR
V02+
V02-
V01+
V01-
VCC1
VIN1+
VIN1-
REV
FWD
S-GND
MUTE
VIN+
VIN4-
VCC-S
FR
VREF-IN
REG-OUT
REG-IN
VIN3-
VIN3+
VIN2-
VIN2+
INPUT
MUTE
Thermal shutdown
Output control Level Shift Level Shift Level Shift Level Shift
CH3,4,5
POWER
CH5
CH4
CH3
CH2
CH1
MUTE is as follows:
High : Output ON
Low : Output OFF
22K 11K
Signal System Power
CH1,2
Power 22K
22K
22K
11K
11K
11K
SVREG (External PNPTr)
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Pin NO. Symbol Function
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
VCC2
V05-
V05+
V04+
V04-
V03+
V03-
V02+
V02-
V01+
V01-
VCC1
VIN1+
VIN1-
VIN2+
VIN2-
VIN3+
VIN3-
REG-IN
REG-OUT
VREF-IN
VCC-S
VIN4-
VIN4+
MUTE
S-GND
FWD
REV
Power for channels 3,4, and 5 (VCC1 and VCC-S short-circuited)
Loading output (-)
Loading output (+)
Output pin (+) for channel 4
Output pin (-) for channel 4
Output pin (+) for channel 3
Output pin (-) for channel 3
Output pin (+) for channel 2
Output pin (-) for channel 2
Output pin (+) for channel 1
Output pin(-) for channel 1
Power for channels 1 and 2 (BTL), (VCC-S and VCC2 short-circuited)
Input pin for channel 1
Input pin for channel 1 (for gain control)
Input pin for channel 2
Input pin for channel 2 (for gain control)
Input pin for channel 3
Input pin for channel 3 (for gain control)
Regulator pin (External PNP base)
Regulator pin (External PNP collector)
Reference voltage input pin
Signal system power (VCC and VCC2 short-circuited)
Input pin for channel 4 (for gain control)
Input pin for channel 4
Output ON/OFF, channels 1 to 4 (BTL AMP)
Signal system GND
5CH(VL0) Output change pin (FWD), Logic input for loading block
5CH(VL0) Output change pin (REV), Logic input for loading block
The center frame (FR) functions as power system GND. Set this to the minimum potential together with S-GND.
Short-circuit three pins of power system, VCC-S, VCC1, and VCC2, externally before use.
3.Pin function
LA6557-X(2/2)
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