JVC KD-S721R, KD-S723R Service Manual
KD-S723R/KD-S721R
SERVICE MANUAL
CD RECEIVER
KD-S723R/KD-S721R
KD-S723R
TP/PTY
SEL
DISP
87 9
10 11
KD-S721R
TP/PTY
SEL
DISP
87 9
10 11
Difference point
KD-S723R LCD Color,Button Illumination--- Amber
KD-S721R LCD Color,Button Illumonation--- Green
Contents
FM
¢
CD
4
RNDRPTMO
12
RNDRPTMO
12
AM
SCMMODE
COMPACT
DIGITAL AUDIO
FM
¢
CD
4
AM
SCMMODE
Area Suffix
E -------- Continental Europe
EX ------------ Central Europe
Safety precaution
Preventing static electricity
Important for laser products
Location of main parts
Disassembly method
COPYRIGHT 2002 VICTOR COMPANY OF JAPAN, LTD.
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1-3
1-4
1-5
1-6
Adjustment method
Flow of functional
operation unit TOC read
Maintenance of laser pickup
Replacement of laser pickup
Description of major ICs
1-11
1-12
1-14
1-14
1-15
No.49693
Feb. 2002
KD-S723R/KD-S721R
Safety precaution
!
!
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.
Please use enough caution not to see the beam directly or touch it in case of an
adjustment or operation check.
1-2
KD-S723R/KD-S721R
Preventing static electricity
Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged,
can destroy the laser diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.
1.1. Grounding to prevent damage by static electricity
Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as DVD players.
Be careful to use proper grounding in the area where repairs are being performed.
1.1.1. Ground the workbench
1. Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over
it before placing the traverse unit (optical pickup) on it.
1.1.2. Ground yourself
1. Use an anti-static wrist strap to release any static electricity built up in your body.
(caption)
Anti-static wrist strap
Conductive material
(conductive sheet) or iron plate
1.1.3. Handling the optical pickup
1. In order to maintain quality during transport and before installation, both sides of the laser diode on the
replacement optical pickup are shorted. After replacement, return the shorted parts to their original condition.
(Refer to the text.)
2. Do not use a tester to check the condition of the laser diode in the optical pickup. The tester's internal power
source can easily destroy the laser diode.
1.2. Handling the traverse unit (optical pickup)
1. Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit.
2. Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific
details, refer to the replacement procedure in the text. Remove the anti-static pin when replacing the traverse
unit. Be careful not to take too long a time when attaching it to the connector.
3. Handle the flexible cable carefully as it may break when subjected to strong force.
4. It is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it
Short circuit land
FD screw
Feed motor ass’y
Shorting
FD gear
Pickup unit
1-3
KD-S723R/KD-S721R
Important for laser products
1.CLASS 1 LASER PRODUCT
2.DANGER : Invisible laser radiation when open and inter
lock failed or defeated. Avoid direct exposure to beam.
3.CAUTION : There are no serviceable parts inside the
Laser Unit. Do not disassemble the Laser Unit. Replace
the complete Laser Unit if it malfunctions.
4.CAUTION : The compact disc player uses invisible
laserradiation and is equipped with safety switches
whichprevent emission of radiation when the drawer is
open and the safety interlocks have failed or are de
feated. It is dangerous to defeat the safety switches.
VARNING : Osynlig laserstrålning är denna del är öppnad
och spårren är urkopplad. Betrakta ej strålen.
VARO : Avattaessa ja suojalukitus ohitettaessa olet
alttiina näkymättömälle lasersäteilylle.Älä katso
säteeseen.
5.CAUTION : If safety switches malfunction, the laser is able
to function.
6.CAUTION : Use of controls, adjustments or performance of
procedures other than those specified herein may result in
hazardous radiation exposure.
CAUTION
!
Please use enough caution not to
see the beam directly or touch it
in case of an adjustment or operation
check.
ADVARSEL : Usynlig laserstråling ved åbning , når
sikkerhedsafbrydere er ude af funktion. Undgå
udsættelse for stråling.
ADVARSEL : Usynlig laserstråling ved åpning,når
sikkerhetsbryteren er avslott. unngå utsettelse
for stråling.
REPRODUCTION AND POSITION OF LABELS
WARNING LABEL
CLASS 1
LASER PRODUCT
DANGER : Invisibie laser
radiation when open and
interlock or defeated.
AVOID DIRECT EXPOSURE
TO BEAM (e)
ADVARSEL :Usynlig laserstråling ved åbning , når
sikkerhedsafbrydere er ude
af funktion. Undgå udsæt
telse for stråling. (f)
VARNING : Osynlig laserstrålning är denna del
är öppnad och spårren är
urkopplad. Betrakta ej
strålen. (s)
VARO : Avattaessa ja suojalukitus ohitettaessa olet
alttiina näkymättömälle
lasersäteilylle.Älä katso
säteeseen. (d)
1-4
Location of main parts
Control unit
Display
Main unit
KD-S723R/KD-S721R
LED & key control board
Main board
CD mechanism
Power IC
Mechanism relay board
ISO connector
Main board
Loading motor
Antenna jack
Tuner
pack
Connector to controller
Damper
Pickup unit
Spindle motor
Feed motor
Damper
1-5
KD-S723R/KD-S721R
Disassembly method
Removing the front panel unit
(See Fig.1)
1. Press the release button and remove the front
panel unit in the direction of the arrow.
Fig.1
Removing the front chassis (See Fig.2)
1. Insert a screwdriver to the joints a on the side of the
front chassis and two joints b on the right side, then
detach the front chassis toward the front side.
Removing the heat sink (See Fig.3)
1. Remove the three screws A attaching the heat sink
on the left side of the body, and remove the heat
sink.
A
a
a
Front chassis
Fig.2
A
Fig. 3
b
b
A
Heat sink
Removing the bottom cover (See Fig.4)
1.2.Turn the body upside down.
Insert a screwdriver to the two joints c and two
joints d on both sides of the body and the joint e on
the back of the body, then detach the bottom cover
from the body.
1-6
Bottom cover
c
d
e
Fig. 4
KD-S723R/KD-S721R
Removing the main amplifier board
(See Fig.5 and 6)
1.
Remove the front chassis.
2.
Remove the bottom cover.
3.
Remove the two screws B attaching the main
amplifier board assembly on the bottom of the body.
4.
Remove the three screws C attaching the main
amplifier board assembly on the back of the body.
5.
Disconnect connector CN501 on the main amplifier
board assembly from the CD mechanism assembly.
Main amplifier board
B
C
CN501
B
Fig.5
C
C
Fig. 6
Removing the CD mechanism assembly
(See Fig.7)
1.
Remove the front chassis.
2.
Remove the bottom cover.
3.
Remove the main amplifier board assembly.
4.
Remove the three screws D attaching the CD
mechanism assembly from the top cover.
Removing the control switch board
(See Fig.8 and 9)
1.
Remove the front chassis.
2.
Remove the four screws E attaching the rear cover
on the back of the front panel unit.
3.
Remove the control switch board from the front
panel unit.
CD mechanism assembly
Top cover
D
E
E
D
Fig. 7
E
Fig. 8
Control switch board
D
E
Fig. 9
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KD-S723R/KD-S721R
<CD mechanism section>
Removing the CD mechanism control
board (See Fig.1 and 2)
1.
Unsolder the part a and b on the CD mechanism
control board.
2.
Remove the stator fixing the CD mechanism control
board and the damper bracket (To remove the stator
smoothly, pick up the center part).
3.
Remove the screw A attaching the CD mechanism
control board.
4.
Remove the CD mechanism control board in the
direction of the arrow while releasing it from the two
damper bracket slots d and the front bracket slot e.
5.
Disconnect the flexible wire from connector on the
pickup unit.
ATTENTION:
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)
CD mechanism assembly
D
h
Front bracket
Pickup unit
Damper bracket
D
A
Fig.1
e
b
Flexible wire
a
h
c
D
d
CD mechanism
control board
Shift the lock
Removing the loading motor
(See Fig.3 to 5)
Prior to performing the following procedure, remove
the CD mechanism control board.
1.
Remove the two springs f attaching the CD
mechanism assembly and the front bracket.
2.
Remove the two screws B and the front bracket
while pulling the flame outward.
3.
Remove the belt and the screw C from the loading
motor.
Loading motor
C
FD gear
f
B
Loading motor
Pull outward
Fig.2
CD mechanism control board
f
B
Front bracket
Fig.3
Front bracket
Pull outward
1-8
Fig.5
Belt
Flame
Fig.4
KD-S723R/KD-S721R
Removing the CD mechanism assembly
(See Fig.1, 6 to 9)
Prior to performing the following procedure, remove
the CD mechanism control board and the front
bracket (loading motor).
1.
Remove the three screws D and the damper
bracket.
2.
Raise the both sides fix arms and move the fix plates
in the direction of the arrow to place the four shafts g
as shown in Fig.8 and 9.
3.
Remove the CD mechanism assembly and the two
springs h attaching the flame.
4.
Remove the two screws E and both sides rear
damper brackets from the dampers. Detach the CD
mechanism assembly from the left side to the right
side.
ATTENTION:
The CD mechanism assembly can be
removed if only the rear damper
bracket on the left side is removed.
CD mechanism
h
Front bracket
CD mechanism
D
Flame
assembly
D
assembly
h
D
Damper bracket
D
A
Fig.5
e
b
Damper bracket
D
Fig.6
a
h
c
D
d
CD mechanism
control board
h
Fix plate (L)
g
Fix arm (R)
D
Fig.7
Rear damper bracket
g
Fig.8
Rear damper bracket
E
Fix plate(R)
E
Fix arm (L)
Damper
Damper
g
g
Fig.9
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