Jvc MX-GT90 Service Manual
MX-GT80/MX-GT90
SERVICE MANUAL
COMPACT COMPONENT SYSTEM
MX-GT80 / MX-GT90
STANDBY/ON
STANDBY
CD-R/RW PLAYBACK
MX-GT80
CA-MXGT80SP-MXGT80
Each different point
Model
MX-GT80
MX-GT90
CD/DECK/RECEIVER
CA-MXGT80
CA-MXGT90
PLAY & EXCHANGE
SP-MXGT80
SPEAKER
SP-MXGT80
SP-MXGT90
Area Suffix
J
C
STANDBY/ON
STANDBY
CD-R/RW PLAYBACK
MX-GT90
CA-MXGT90SP-MXGT90
OUTPUT POWER
55W / ch 130W / ch
70W / ch
PLAY & EXCHANGE
SP-MXGT90
SUB WOOFERMAIN SPEAKER
160W / ch
U.S.A.
Canada
Contents
Safety precautions
Important for laser products
Preventing static electricity
Importance administering
point on the safety
Disassembly method
Adjustment method
COPYRIGHT 2001 VICTOR COMPANY OF JAPAN, LTD.
1-2
1-3
1-4
1-5
1-6
1-28
Flow of functional operation
until TOC read
Maintenance of laser pickup
Replacement of laser pickup
Description of major ICs
1-32
1-33
1-33
1-34
No.20912
Feb. 2001
MX-GT80/MX-GT90
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.
AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)
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.).
0.15 F AC TYPE
1500 10W
Place this
probe on
each exposed
metal part.
This corresponds to 0.5 mA AC (r.m.s.).
Good earth ground
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.
!
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.
1-2
Important for laser products
MX-GT80/MXGT90
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 laser
radiation and is equipped with safety switches which
prevent emission of radiation when the drawer is open and
the safety interlocks have failed or are defeated. 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
DANGER : Invisibie laser radiation
when open and interlock or
defeated.
AVOID DIRECT EXPOSURE TO
BEAM (e)
VARO : Avattaessa ja suojalukitus
ohitettaessa olet alttiina
näkymättömälle lasersäteilylle.Älä
katso säteeseen. (d)
VARNING : Osynlig laserstrålning är
denna del är öppnad och spårren är
urkopplad. Betrakta ej strålen. (s)
ADVARSEL :Usynlig laserstråling
ved åbning , når
sikkerhedsafbrydere er ude af
funktion. Undgå udsættelse for
stråling. (f)
1-3
MX-GT80/MX-GT90
Preventing static electricity
1. Grounding to prevent damage by 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.
2. About the earth processing for the destruction prevention by static electricity
In the equipment which uses optical pick-up (laser diode), optical pick-up is destroyed by the static electricity of
the work environment.
Be careful to use proper grounding in the area where repairs are being performed.
2-1 Ground the workbench
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.
2-2 Ground yourself
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
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.
4. 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
Attention when traverse unit is decomposed
*Please refer to "Disassembly method" in the text for pick-up and how to
detach the CD traverse mechanism.
1. Remove the disk stopper and T. bracket on the CD changer mechanism
assembly.
2. Disconnect the harness from connector on the CD motor board.
3. CD traverse unit is put up as shown in Fig.1.
4. Solder is put up before the card wire is removed from connector CN601
on the CD servo control board as shown in Fig. 2.
(When the wire is removed without putting up solder, the CD pick-up
assembly might destroy.)
5. Please remove solder after connecting the card wire with CN601 when
you install picking up in the substrate.
CD changer
mechanism
assembly
CD traverse
unit
Flexible cable
Fig.1
Soldering
Fig.2
1-4
Importance administering point on the safety
F102
F101
F001
MX-GT80/MXGT90
Caution: For continued protection against risk of
fire, replace only with same type 5A/125V for
F001, 6A/125V for F101 and F102. This symbol
specifies type of fast operating fuse.
Precaution: Pour eviter risques de feux, remplacez
le fusible de surete de F001 comme le meme type
que 5A/125V, et 6A/125V pour F101 et F102.
Ce sont des fusibles suretes qui functionnes rapide.
^
1-5
MX-GT80/MX-GT90
Disassembly method
<Main body>
Removing the metal cover
(See Fig.1 to 3)
1.
Remove the six screws A on the back of the body.
2.
Remove the two screws B on both sides of the
body.
3.
Remove the metal cover from the body by lifting the
rear part of the cover.
CAUTION:
Do not break the front panel tab fitted to
the metal cover.
A
Metal cover
Metal cover
AA
Fig.1
B
Fig.2
Metal cover
B
Fig.3
1-6
MX-GT80/MXGT90
Removing the CD changer mechanism
assembly (See Fig.4 and 5)
Prior to performing the following procedure, remove
the metal cover.
1.
Disconnect the card wire from connector CN661 on
the Main board.
2.
Remove the two screws C on the upper side of the
body and the two screws D on the back of the rear
panel.
3.
Remove the plastic rivet attaching the main board.
4.
Pull both the rear panel and the front panel assembly
to the outside, then remove the CD changer
mechanism assembly by lifting the rear part of the
assembly.
CAUTION:
To prevent damage to the CD fitting, be
sure to pull both the rear panel and the
front panel assembly enough to remove
the CD changer mechanism assembly.
Front panel assembly
C
Main board
CN661
Fig.4
CD changer mechanism assembly
Main board
CN661
Plastic rivet
Front panel assembly
Fig.5
C
CD changer
mechanism assembly
Rear panel
Rear panel
D
Removing the front panel assembly
(See Fig.6 to 10)
Prior to performing the following procedure, remove
the metal cover and CD changer mechanism
assembly.
1.
Disconnect the card wires from connector CN870,
CN871 and CN315 on the main board respectively.
2.
Remove the tie band and disconnect the wire from
connector CN703 on the amplifier board.
3.
Disconnect the wire from connector CN220 on the
transformer board.
Amplifier board
CN703
Wire clamp
Fig.6
Main board
CN870
CN871
CN315
Front panel
assembly
Transformer board
CN220
Front panel assembly
Fig.7
Main board
1-7
MX-GT80/MX-GT90
4.
Remove the four screws E on the bottom of the
body.
5.
Release the two joints a on the lower right and left
sides of the body using a screwdriver, and remove
the front panel assembly toward the front.
Front panel assembly
E
(Bottom)
Fig.8
Front panel assembly
Joint a
Joint a
Fig.9
Front panel assembly
Fig.10
1-8
MX-GT80/MXGT90
Removing the tuner board
(See Fig.11 and 12)
Prior to performing the following procedure, remove
the metal cover and the CD changer mechanism
assembly.
1.
Disconnect the card wire from connector CN1 on the
antenna board on the right side of the body.
2.
Remove the plastic rivet fixing the antenna board.
3.
Remove the two screws F on the back of the body.
Removing the rear cover / rear panel
(See Fig.12 to 15)
Prior to performing the following procedure, remove
the metal cover and the CD changer mechanism
assembly.
F
Joint b
CN1
Plastic rivet
Fig.11
G
Tuner board
Rear panel
Rear panel
Joint b
1.
Remove the screw G attaching the rear cover on the
back of the body.
2.
Push each tab of the four joints b in the direction of
the arrow and release.
3.
Remove the eleven screws F attaching the rear
panel.
4.
Release the joints c on each lower side of the rear
panel using a screwdriver and remove the rear panel
backward.
Note : Remove the tuner board in case of necessity.
(Refer to Fig.21)
F
F
F
Rear cover
Fig.12
Rear panel
F
Fig.13
Joint c
Fig.15
Rear panel
Rear panel
Fig.14
Joint c
1-9
MX-GT80/MX-GT90
Removing the main board
(See Fig.16 and 17)
Prior to performing the following procedure, remove
the metal cover, the CD changer mechanism
assembly, the rear panel and the tuner board.
1.
Disconnect the card wires from connector CN870,
CN871 and CN315 on the main board.
2.
Disconnect the flat wires from connector CN704 and
CN706 on the amplifier board.
3.
Remove the screw H attaching the main board on
the right side of the body.
4.
Disconnect connector CN211 and CN212 on the
main board from the regulator board.
CN315
Amplifier board
CN704
CN706
Front panel assembly
Main board
CN871
Plastic rivet
CN870
Fig.16
Front panel assembly
Main board
Removing the speaker board
(See Fig.18)
Prior to performing the following procedure, remove
the metal cover, the CD changer mechanism
assembly and the rear panel.
REFERENCE:
1.
Disconnect connector CN217 on the speaker board
from the regulator board.
It is not necessary to remove the main
board.
Regulator board
Regulator board
H
Fig.17
Fig.18
CN212
CN211
Speaker board
CN217
1-10
MX-GT80/MXGT90
Removing the amplifier board / voltage
board / heat sink (See Fig.19 and 20)
Prior to performing the following procedure, remove
the metal cover, the CD changer mechanism
assembly and the rear panel.
1.
Disconnect the wires from connector CN703, CN704
and CN706 on the amplifier board respectively.
2.
Remove the two tie band attaching the wire to the
amplifier board and the voltage board.
3.
Disconnect connector CN215 on the amplifier board
and CN216 on the voltage board from the regulator
board (The heat sink and heat sink bracket will be
detached at once).
4.
Pull out the upper and lower heat sink brackets from
the heat sink respectively.
5.
Remove the four screws I attaching the amplifier
board to the heat sink.
6.
Remove the two screws J, the board bracket and
the voltage board.
Tie band
Voltage board
Regulator board
Heat sink
Voltage board
Amplifier board
CN703
CN704
CN216
Heat sink bracket
Tie band
CN703
CN215
Fig.19
Amplifier board
I
J
Heat sink bracket
I
Fig.20
1-11
MX-GT80/MX-GT90
Removing the power transformer
assembly (See Fig.21 and 22)
Prior to performing the following procedure, remove
the metal cover, the CD changer mechanism
assembly and the rear panel.
1.
Disconnect the wires from connector CN220 and
CN250 on the transformer board.
2.
Disconnect the wire from connector CN204 on the
regulator board.
3.
Remove the four screws k attaching the transformer
assembly.
Removing the regulator board
(See Fig.23)
Prior to performing the following procedure, remove
metal cover, CD changer mechanism assembly, rear
panel, tuner board, main board, amplifier board,
voltage board and speaker board.
Voltage board
Power cord
Base chassis
Regulator board
CN204
Transformer board
Tie band
Power cord stopper
Fig.21
Transformer board
CN220
CN250
CN220
Power transformer assembly
K
Power transformer
assembly
1.
Disconnect the wire from connector CN204 on the
regulator board.
2.
Remove the two screws L attaching the regulator
board.
Removing the power cord (See Fig.21)
Prior to performing the following procedure, remove
the metal cover, the CD changer mechanism
assembly and the rear panel.
1.
Disconnect the wire from connector CN250 on the
transformer board.
2.
Remove the tie band from the voltage board.
3.
Move the power cord stopper upward and pull out it
from the base chassis.
CN250
CN204
L
Regulator board
K
Tie band
Power cord stopper
Fig.22
Power transformer assembly
L
Fig.23
1-12
MX-GT80/MXGT90
<Front panel assembly>
Prior to performing the following procedure, remove
the metal cover, the CD changer mechanism
assembly and the front panel assembly.
Removing the cassette mechanism
assembly (See Fig.24)
1.
Disconnect the card wire from connector CN306 on
the head amplifier & mechanism control board.
2.
Remove the four screws M and three screws M'
attaching the cassette mechanism assembly.
Removing the display system control
board (See Fig.25 to 27)
1.
Remove the five screws N attaching the stay bracket.
2.
Disconnect the card wires from connector CN316 and
CN880 on the display system control board.
Head amplifier
& Mechanism control board
CN306
M
M'
Cassette mechanism
assembly
Fig.24
N
M
M
M'
M'
N
3.
Remove the seven screws O attaching the display
system control board.
4.
If necessary, disconnect the wire from connector
CN911 on the front side of the display system control
board and unsolder FW915.
If necessary, remove the CD play board. (Fig. 28)
Removing the CD play board
(See Fig.27 and 28)
1.
Remove the three screws P attaching the CD eject
board.
2.
If necessary, unsolder FW915 on the CD eject
board.
CD playt board
FW915
(Soldering)
P
P
Display system control board
O
FW915
(Soldering)
O
Fig.25
O
CN316
CN880
Fig.26
CN911
Stay bracket
O
O
Display system control board
CD play board
FW915
Display system control board
FW915
Fig.27Fig.28
1-13
MX-GT80/MX-GT90
Removing the preset / tuning switch
board (See Fig.29 and 30)
Prior to performing the following procedure, remove
the display system control board.
1.
Pull out the preset knob on the front panel.
2.
Remove the five screws Q attaching the preset /
tuning switch board.
3.
If necessary, unsolder FW901 on the preset / tuning
switch board.
Removing the operation switch board
(See Fig.30 and 31)
Prior to performing the following procedure, remove
the display system control board and the preset /
tuning switch board.
1.
Pull out the volume knob on the front panel and
remove the nut. Pull out the surround mode knob
and the surround woofer level knob toward the front.
Q
Preset / tuning switch board
Q
Fig.29
Preset knob
Surround mode knob
Surround woofer
level knob
2.
Remove the twelve screws R attaching the
operation switch board.
3.
Remove the screw R' attaching the earth terminal
extending from the switch board.
4.
Release each tab of the seven joints g retaining the
operation switch board.
Joint g
Joint g
R
R
Joints g
Nut
Volume knob
Fig.30
R
Operation
switch board
1-14
R
Joints g
R
Fig.31
R
R
Joint g
R'
MX-GT80/MXGT90
Speaker section 1
(SP-MXGT80)
Removing the front panel (See Fig.1)
1.
Remove the four screws A attaching the front panel
on the front of the body.
2.
Pull out the front panel toward the front.
Removing the speaker (tweeter)
(See Fig.2)
Prior to performing the following procedures, remove
the front panel.
1.
Remove the two screws B attaching the speaker
(tweeter) on the front of the body.
2.
Disconnect the wire from two speaker terminals of
the speaker (tweeter).
AA
Front panel
AA
Fig.1
B
Removing the speaker (squawker)
(See Fig.3)
Prior to performing the following procedures, remove
the front panel.
1.
Remove the four screws C attaching the speaker
(squawker) on the front of the body.
2.
Disconnect the wire from the two speaker terminals
of the speaker (squawker).
Speaker (squawker)
Speaker (tweeter)
Fig.2
Speaker (squawker)
C
C
Fig.3
1-15
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