JVC MX-S6MD User manual

SERVICE MANUAL
COMPACT COMPONENT MD SYSTEM
No.20887
Nov. 2000
COPYRIGHT 2000 VICTOR COMPANY OF JAPAN, LTD.
MX-S6MD
MX-S6MD
Safety Precautions
Preventing static electricity
Important for laser products
Disassembly method
Adjustment method
Flow of functional operation
until TOC read (MD section)
Maintenace of laser pickup (MD)
Replacement of laser pickup (MD)
Flow of functional operation
until TOC read (CD section)
Maintenance of laser pickup (CD)
Replacement of laser pickup (CD)
Description of major ICs
1-2
1-3
1-4
1-5
1-31
1-37
1-38
1-38
1-39
1-40
1-40
1-40~69
Area Suffix
US
UB
UT
Singapore
Hong Kong
Taiwan
CA-MXS6MDSP-MXS6MD SP-MXS6MD
Contents

MX-S6MD
1-2
1. This design of this product contains special hardware and many circuits and components specially
for safety purposes. For continued protection, no changes should be made to the original design
unless authorized in writing by the manufacturer. Replacement parts must be identical to those
used in the original circuits. Services should be performed by qualified personnel only.
2. Alterations of the design or circuitry of the product should not be made. Any design alterations of
the product should not be made. Any design alterations or additions will void the manufacturer`s
warranty and will further relieve the manufacture of responsibility for personal injury or property
damage resulting therefrom.
3. Many electrical and mechanical parts in the products have special safety-related characteristics.
These characteristics are often not evident from visual inspection nor can the protection afforded
by them necessarily be obtained by using replacement components rated for higher voltage,
wattage, etc. Replacement parts which have these special safety characteristics are identified in
the Parts List of Service Manual. Electrical components having such features are identified by
shading on the schematics and by ( ) on the Parts List in the Service Manual. The use of a
substitute replacement which does not have the same safety characteristics as the recommended
replacement parts shown in the Parts List of Service Manual may create shock, fire, or other
hazards.
4. The leads in the products are routed and dressed with ties, clamps, tubings, barriers and the
like to be separated from live parts, high temperature parts, moving parts and/or sharp edges
for the prevention of electric shock and fire hazard. When service is required, the original lead
routing and dress should be observed, and it should be confirmed that they have been returned
to normal, after re-assembling.
5. Leakage currnet check (Electrical shock hazard testing)
After re-assembling the product, always perform an isolation check on the exposed metal parts
of the product (antenna terminals, knobs, metal cabinet, screw heads, headphone jack, control
shafts, etc.) to be sure the product is safe to operate without danger of electrical shock.
Do not use a line isolation transformer during this check.
Plug the AC line cord directly into the AC outlet. Using a "Leakage Current Tester", measure
the leakage current from each exposed metal parts of the cabinet , particularly any exposed
metal part having a return path to the chassis, to a known good earth ground. Any leakage
current must not exceed 0.5mA AC (r.m.s.)
Alternate check method
Plug the AC line cord directly into the AC outlet. Use an AC voltmeter having, 1,000 ohms
per volt or more sensitivity in the following manner. Connect a 1,500 10W resistor paralleled by
a 0.15 F AC-type capacitor between an exposed
metal part and a known good earth ground.
Measure the AC voltage across the resistor with the
AC voltmeter.
Move the resistor connection to eachexposed metal
part, particularly any exposed metal part having a
return path to the chassis, and meausre the AC
voltage across the resistor. Now, reverse the plug in
the AC outlet and repeat each measurement. voltage
measured Any must not exceed 0.75 V AC (r.m.s.).
This corresponds to 0.5 mA AC (r.m.s.).
1. This equipment has been designed and manufactured to meet international safety standards.
2. It is the legal responsibility of the repairer to ensure that these safety standards are maintained.
3. Repairs must be made in accordance with the relevant safety standards.
4. It is essential that safety critical components are replaced by approved parts.
5. If mains voltage selector is provided, check setting for local voltage.
Good earth ground
Place this
probe on
each exposed
metal part.
AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)
1500 10W
0.15 F AC TYPE
!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.

MX-S6MD
1-3
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 CD/MD 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.
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
Conductive material
(conductive sheet) or iron plate
(caption)
Anti-static wrist strap
CN321
CN451
Pickup Soldering part
Main board Flexible board
Soldering part
MD pickup CD pickup
Preventing static electricity

MX-S6MD
1-4
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.
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.
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.
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 LABEL
WARNING LABEL
CLASS 1
LASER PRODUCT
!CAUTION Please use enough caution not to
see the beam directly or touch it
in case of an adjustment or operation
check.
DANGER : Invisibie laser radiation
when open and interlock or
defeated.
AVOID DIRECT EXPOSURE TO
BEAM (e)
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)
ADVARSEL :Usynlig laserstråling
ved åbning , når
sikkerhedsafbrydere er ude af
funktion. Undgå udsættelse for
stråling. (f)

MX-S6MD
1-5
Remove the four screws Aon the back of the body.
Remove the two screws Bon both sides of the body.
Lift up the rear part of the top cover while pulling
both sides, then remove the top cover.
1.
2.
3.
Disassembly method
<Main body>
Removing the top cover
(See Fig. 1 and 2)
Prior to performing the following procedure, remove
the top cover.
Disconnect the card wire from connector CN661 on
the input board.
Remove the four screws Con the upper side of the
body.
Remove the screw Don the left side of the body.
Release the wires from the clamp on the right side of
the CD changer mechanism assembly. Lift up the
rear part of the CD changer mechanism assembly
and pull out it from the front assembly.
1.
2.
3.
4.
Removing the CD changer mechanism
assembly (See Fig.3 to 5)
Fig.1
Fig.2
Fig.3
Fig.4Fig.5
Top cover A
A
A
A
A
A
CC
Bx2
A
Top cover
CD changer mechanism assembly
CD changer mechanism assembly
CD changer mechanism assembly
Clamp
Input board
Front panel assembly
CN661
CC
D

MX-S6MD
1-6
Prior to performing the following procedure, remove
the top cover.
Disconnect the wire from connector CN603 on the
input board and the card wire from CN801 on the
microcomputer board.
Remove the two screws Eon the bottom of the body.
Release the joint aon the bottom and the two joints
band con the lower sides of the body using a
screwdriver. Detach the front panel assembly toward
the front.
1.
2.
3.
Removing the font panel assembly
(See Fig.6 to 8)
Prior to performing the following procedure, remove
the top cover and the front panel assembly.
Remove the nine screws F attaching the display
board to the front panel assembly.
Disconnect connector CN791 on the display board
from the control board on the front panel assembly.
1.
2.
Removing the display board (See Fig.9)
Prior to performing the following procedure, remove
the top cover, the front panel assembly and the
display board.
Remove the five screws Gand the four screws H
attaching the control board and the key board.
1.
Removing the control board / the key
board (See Fig.10)
When removing the control board and
the key board respectively, unsolder
each board.
REFERANCE :
Fig.8
Front panel assembly Joint a
Joint b
Joint c
Front panel assembly
CN603
CN801
Microcomputer board
Display board
Key board
Control board
Input board
EE
F
G
G
G
H
H
F
F
F
Fig.6
Fig.7
Fig.9
Fig.10
Front panel assembly
Front panel assembly
Soldering
Front panel assembly
CN791

MX-S6MD
1-7
Prior to performing the following procedure, remove
the top cover and the CD changer mechanism
assembly.
Disconnect the card wire from connectors CN511 on
the main board.
Remove the four screws Ion both sides of the body.
Pull out the MD changer mechanism assembly from
behind upward while releasing the four joints dusing
a screwdriver.
1.
2.
3.
Removing the MD changer mechanism
(See Fig.11 to 13 )
Prior to performing the following procedure, remove
the top cover.
Disconnect the card wire from connector CN801 on
the microcomputer board.
Remove the screw Dattaching the microcomputer
board.
Disconnect the lower connector CN391, CN392 and
CN393 from the main board by pulling them.
1.
2.
3.
Removing the microcomputer board
(See Fig.14)
MD changer
mechanism assembly
CN511
Microcomputer board
CN801
CN393
CN392
CN391
Joints d
I
I
D
Fig.11
Fig.12
Fig.13
Fig.14
MD changer
mechanism assembly
MD changer mechanism assembly
Joints d

MX-S6MD
1-8
Prior to performing the following procedure, remove
the top cover.
Disconnect the wire from connector CN
111 and
CN112 on the tuner board.
Remove the screw Jon the side of the body .
Remove the two screws Kon the back of the rear
panel.
1.
2.
3.
Removing the tuner board
(See Fig.15 and 16)
Prior to performing the procedure, remove the top
cover.
Remove the two screws Land the two screws L'
attaching the rear cover to the body.
Remove the two screws K, M, N, O, and the screw P
and Qrespectively.
Release the joint eon the lower left side of the rear
panel.
1.
2.
3.
Remove the rear cover / the rear panel
(See Fig.15 to 17)
Prior to performing the procedure, remove the top
cover, the rear cover, the rear panel and the tuner
board.
Disconnect the card wire from connector CN661 and
the wire from CN603 on the input board.
Remove the two screws Rattaching the bracket and
remove the bracket in the direction of the arrow.
Disconnect the lower connector CN602, CN913 and
CN922 from the main board. Disconnect the wire
from CN691 on the input board.
1.
2.
3.
Removing the Input board (See Fig.18)
To facilitate the procedure, remove the
rear panel in advance.
REFERANCE :
CN111 Rear cover
CN661
CN603
Input board
CN691
CN602
CN913
CN922
Joint e
Tuner board
J
K
L
L
O
Q
K
M
N
R
P
Fig.15
Fig.16
CN112
Rear panel
Rear panel
Fig.17
Fig.18
L'

MX-S6MD
1-9
Prior to performing the procedure, remove the top
cover, the CD changer mechanism assembly, the
rear cover, the rear panel, the tuner board and the
input board.
Remove the four screws Sattaching the bracket.
Disconnect connector CN924 and CN394 from the
main board.
1.
2.
Removing the heat sink assembly
(See Fig.19 and 20)
Prior to performing the procedure, remove the top
cover, the CD changer mechanism assembly, the
rear cover, the rear panel, the tuner board, the input
board and the heat sink assembly.
Remove the two screws Tor Uattaching the
regulator board and the amplifier board to the heat
sink.
1.
Removing the regulator board / the
amplifier board (See Fig.21)
Heat sink assembly
Heat sink assembly
Heat sink
Bracket
CN924
Main board
Amplifier board
Regulator board
CN394
S
U
T
S
Fig.19
Fig.20
Fig.21

MX-S6MD
1-10
Prior to performing the procedure, remove the top
cover, the CD changer mechanism assembly, the
rear cover, the rear panel, the tuner board, the input
board and the heat sink assembly.
Disconnect the wire from connector CN911 on the
main board and CN991 on the power transformer
assembly.
Disconnect the card wire from connector CN511 on
the main board.
Remove the four screws Vattaching the main
board.
If necessary, unsolder the wire on the headphone
board.
1.
2.
3.
4.
Removing the Main board (See Fig.22)
Prior to performing the procedure, remove the top
cover, the CD changer mechanism assembly, the
front panel assembly, the rear cover, the rear panel,
the tuner board and the input board.
Remove the screw Xattaching the headphone
board.
If necessary, unsolder the wire on the headphone
board.
1.
Removing the headphone board
(See Fig.25)
Prior to performing the following procedure, remove
the top cover, the rear cover, the voltage selector.
Remove the four screws W attaching the power
transformer assembly.
Pull out the power cord stopper from the body
upward. Turn the power transformer assembly while
lifting it as shown in the figure.
Disconnect the wire from connector CN911 on the
main board and CN991 on the power transformer
board. Remove the power transformer assembly
from the body.
1.
2.
3.
Removing the power transformer
assembly (See Fig.23 and 24)
Main board
CN911
CN991
CN511
Soldering
Power cord stopper
Power transformer assembly
Power transformer assembly
Main board
Headphone board Soldering
V
WW
X
V
CN911
CN991
Fig.22
Fig.23
Fig.24
Fig.25

MX-S6MD
1-11
Prior to performing the following procedure, remove
the top cover and the rear cover.
Remove the plastic rivet retaining the voltage
selector.
Disengage the joint fto release the voltage selector
from the transformer bracket. If necessary, unsolder
each wire.
1.
2.
Removing the voltage selector
(See Fig.26)
Fig.26
Joint f
Voltage selector
Plastic rivet

MX-S6MD
1-12
Turn over the body and disconnect the card wire
from connector CN408 and the flexible wire from
CN407 on the main board.
Remove the two screws A attaching the main board.
Slide the main board in the direction of the arrow to
release the two joints a with the single flame.
Solder part b on the pickup in the body. Disconnect
the flexible harness from connector CN321 and
CN451 on the underside of the main board. Then
remove the main board.
1.
2.
3.
Removing the main board
(See Fig.1 and 2)
Remove the four screws B on both sides of the
body.
Move the mechanism cover toward the front to
disengage the front hook of the mechanism cover
from the internal loading assembly (Joint c). Then
remove the mechanism cover upward.
1.
2.
Removing the mechanism cover
(See Fig.3)
<MD section>
Fig.1
Fig.2
Fig.3
AA
Main board
(Bottom)
CN408
CN321
CN451
Pickup
Joint c
Fook
Joint c
Mechanism cover
Solder part b
CN407
Joint b Joint b
Main board
B
B

MX-S6MD
1-13
Move the head lifter on top of the body in the
direction of the arrow and turn around.
Detach the spring from the hook of the body.
Remove the head lifter with the spring.
If necessary, remove the spring from the head lifter.
1.
2.
3.
Removing the head lifter (See Fig.4 to 6)
Remove the screw C on the upper side of the body.
Remove the head assembly while pulling the flexible
harness from the body.
1.
Removing the head assembly (See Fig.7)
Fig.4
Fig.5
Fig.6
Fig.7
C
Head lifter
Spring
Spring
Head lifter
Head assembly
Head lifter

MX-S6MD
1-14
Prior to performing the following procedure, remove
the main board, the mechanism cover, the head lifter
and the head assembly.
Remove the three screws D on the upper side of the
body.
Move the loading assembly forward to disengage it
from the traverse mechanism assembly (Joint d).
Then remove it upward.
Remove the traverse mechanism assembly from the
single flame.
1.
2.
3.
Removing the Loading assembly
(See Fig.8 and 9)
The loading assembly, the traverse mechanism
assembly and the single flame will be
removable after removing the loading assembly
from the body.
Ref:
Fig.8
Fig.9
D
Loading assembly
Joint d
D
D
Loading assembly
Traverse mechanism
assembly
Single flame

MX-S6MD
1-15
Remove the two screws E on the upper side of the
loading assembly.
Remove the slide base (L) outward. (Release it from
the joint bosses E.)
Remove the slide base (R) outward.
1.
2.
3.
Removing the slide base (L) / (R)
(See Fig.10)
Detach the loading mechanism assembly upward to
release the four pins on both sides from the loading
motor, paying attention to the part e of the loading
mechanism base.
1.
Removing the loading mechanism
assembly (See Fig.11)
Disconnect the harnesses from the wire holder and
from connector CN612 on the cam switch board.
Remove the screw F attaching the loading motor
and release the joint f.
Remove the belt from the loading motor assembly.
Remove the two screws G attaching the loading
motor.
1.
2.
3.
4.
Removing the loading motor
(See Fig.12 and 13)
Loading mechanism assembly
Remove the slit washer attaching the cam gear and
pull out the cam gear.
Disconnect the harness from the wire holder and
from connector CN612 on the cam switch board.
Remove the two screws H and the clamp. Remove
the cam switch board.
1.
2.
3.
Removing the cam gear and the cam
switch board (See Fig.12)
<Loading assembly>
Fig.10
Fig.11
Fig.12
Fig.13
E'
E'
E
E
Loading motor assembly
Loading mechanism
assembly
Loading mechanism base
Slide base (R)
Slide base (L)
F
H
H
Joint f
Part e
CN612
Slit washer
Cam gear
Loading motor
Cam switch board
Wire holder
Belt
G

MX-S6MD
1-16
Remove the two screws I on the upper side of the
loading assembly.
1.
Removing the cartridge holder assembly
(See Fig.14 and 15)
Prior to performing the following procedure, remove
the cartridge holder assembly.
Remove the slide bar upward.
Move the eject bar outward until it stops as shown in
Fig.14. Push the convex part g on the bottom of the
body and remove the eject bar from the chassis.
1.
2.
Removing the slide bar and the eject bar
(See Fig.14 and 15) Fig.14
Fig.15
I
I
I
Slide bar
Slide bar
Eject bar
Part g
Cartridge holder assembly
Cartridge holder assembly
Eject bar
Eject bar
k
UD base

MX-S6MD
1-17
Disengage the four insulators from the notches of the
traverse mechanism chassis.
1.
Removing the Insulators (See Fig.16)
Turn over the traverse mechanism assembly and
remove the screw J attaching the shaft holder (F).
Move the shaft inward and remove it from the shaft
holder (R).
Detach the shaft side of the pickup unit upward and
release the joint h with the pickup guide. Then
remove the pickup unit with the shaft.
1.
2.
3.
Removing the pickup unit (See Fig.17)
Draw out the shaft from the pickup.
Remove the two screws K attaching the rack spring.
1.
2.
Removing the pickup (See Fig.18)
<Traverse mechanism assembly>
Fig.16
Fig.17
Fig.18
K
J
Insulators
Insulators
Joint h Pickup guide
Pickup unit
Shaft holder (F)
Shaft holder (R)
Pickup unit
Traverse machanism chassis
Shaft
Pickup
Rack spring

MX-S6MD
1-18
It is not necessary to remove the pickup unit.
For the white and black harnesses extending from
the feed motor assembly, unsolder the soldering i on
the traverse mechanism board.
Remove the two screws L attaching the feed motor
assembly.
Remove the two screws N attaching the feed motor
bracket.
1.
2.
3.
Removing the feed motor assembly
(See Fig.19-1, 19-2)
Prior to performing procedure, remove the feed
motor assembly.
For the red and black harnesses extending from the
spindle motor, unsolder the soldering j on the
traverse mechanism board.
Remove the screw M attaching the traverse
mechanism board.
1.
2.
Removing the traverse mechanism
board (See Fig.19-1)
Fig.19-1
Fig.19-2
M
L
N
Feed motor assembly
Feed motor
Feed motor bracket
Traberse mechanism board Soldering j
Soldering i

MX-S6MD
1-19
Reattach the eject bar to the UD base.
(Fig.15 and 20)
Reattach the slide bar to the loading mechanism
chassis while fitting the boss marked k to the eject
bar slot. (Fig.20)
Slide the slide bar and the eject bar in the direction
of the arrow in Fig.20 and reattach the cartridge
holder assembly using the two screws I.
(Fig.20 and 21)
1.
2.
3.
<Reattaching the loading assembly>
Make sure the pin of the eject lever
marked l is fitted to the slot of the eject
bar marked m at the bottom of the
loading mechanism chassis after
moving the eject lever and the loading
slider of the cartridge holder assembly
in the direction of the arrow.
(Refer to Fig.21)
ATTENTION:
Fig.20
Fig.21
I
I
H
H
UD base
UD base (Bottom)
Ditch m
Cam switch board
Point marked
Ditch
Cam switch boss
Slide bar
Eject bar
Eject lever
l
Loading slider
Cartridge holder assembly

MX-S6MD
1-20
Reattach the wire holder to the UD base while
engaging the UD base hook marked u to the wire
holder slot marked t (At the same time, the boss on
the reverse side of the wire holder is fitted to the UD
base round hole).
Reattach the cam switch board using the two screws
H. (Fig.22)
Turn the cam switch to bring the boss to the point
marked on the cam switch board. Reattach the
cam gear using a slit washer while fitting the cam
gear slot to the cam switch boss. (Fig.22)
4.
5.
6.
Reattach the loading motor assembly, using the
screw F. Connect the harness extending from the
loading motor to connector CN612 on the switch
board and fix it with the wire holder. (Fig.22)
7.
When reattaching the cam gear, the
cam switch boss should be fitted to the
cam gear slot, and the triangle mark of
the cam gear should be aligned to the
hole of the eject bar as shown in
Fig.22.
ATTENTION:
Fig.22
F
Cam switch
Boss
Point marked
Cam switch board
Cam gear
Slide bar CN612
Loading motor assembly
Eject lever
Eject lever
Cam gear
(Triangle mark)
n