JVC UX-A7DVD User manual

SERVICE MANUAL
COPYRIGHT © 2003 VICTOR COMPANY OF JAPAN, LTD. No.22013
2003/03
UX-A7DVD
MICRO COMPONENT SYSTEM
22013200303 UX-A7DVD
TABLE OF CONTENTS
1 Important Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
2 Disassembly method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
3 Adjustment method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
4 Description of major ICs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-41
DVD/ S U P E R V C D/V C D/ C D
DVD
AU
T O R E V E R S E
COMPACT
SUPERVIDEO
UX-A7DVD
DIGITAL
T A P E
AUX/MD R E V.MOD E
B A SS F M/AM
T R E B L E
MU L T I C O L O R DI S P L AY
3¥WAY S P E AK E R S Y S T E M3¥WAY S P E AK E R S Y S T E M
ANGLE
AUDIO
123
456
789
10 0 +10
DIMMER
CANCEL
TOP MENU
SET
STROBE
PREV.
FADE
MUTING
BASS/
TREBLE
FM MODE
DIGITAL
ECHO
KEY
CONTROL
KEY
CONTROL 3D PHONIC AHBPRO
NEXT
RETURN
SLOW
RM-SUXA7DVDU REMOTE CONTROL
GROUP SKIP
Ð+
SLOW
AUX/MD
DVD
S E L E C T
F M/AM
VO L UM E
S HI F T
T A P E
E N T E R
MENU CHOICE
COLOR
ON SCREEN
PLAYMODE
ZOOM
SUB TITLE
REV.MODE
DIGEST
CLOCK/TIMER
STANDBY / ON
DISPLAY
SLEEP
DVD
LEVEL
AP
OFF
DIGITAL
COMPACT
SUPER VIDEO
Area suffix
US ------------------- Singapore
UN ------------------------ Asean

UX-A7DVD
1-2 (No.22013)
SECTION 1
Important Safety Precautions
1.1 Safety Precautions
(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 man-
ufacturer. Replacement parts must be identical to those
used in the original circuits. Services should be per-
formed 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 manufacturers 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 characteris-
tics are often not evident from visual inspection nor can the
protection afforded by them necessarily be obtained by us-
ing replacement components rated for higher voltage, watt-
age, etc. Replacement parts which have these special safety
characteristics are identified in the Parts List of Service Manu-
al. Electrical components having such features are iden-
tified by shading on the schematics and by ( )onthe
Parts List in the Service Manual. The use of a substitute re-
placement which does not have the same safety character-
istics as the recommended replacement parts shown in the
Parts List of Service Manual may create shock, fire, or oth-
er 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 reassembling.
(5) Leakage shock hazard testing)
After reassembling 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, particular-
ly any exposed metal part having a return path to the
chassis, to a known good earth ground. Any leakage cur-
rent 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 ohm 10W resistor
paralleled by a 0.15 µF 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 each exposed metal part,
particularly any exposed metal part having a return path to
thechassis,andmeasuretheACvoltage 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.).
1.2 Warning
(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.
1.3 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 pre-
forming repair of this system.
1.4 Critical parts for safety
In regard with component parts appearing on the silk-screen
printed side (parts side) of the PWB diagrams, the parts that are
printed over with black such as the resistor ( ), diode ( )
and ICP ( ) or identified by the " " mark nearby are critical
for safety.
When replacing them, be sure to use the parts of the same type
and rating as specified by the manufacturer. (Except the JC version)

UX-A7DVD
(No.22013)1-3
1.5 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.
1.5.1 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) 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) Ground yourself
Use an anti-static wrist strap to release any static electricity built up in your body.
(3) Handling the optical pickup
• 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.)
• 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.
1.6 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 replace-
ment 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.
1.7 Attention when traverse unit is decomposed
*Please refer to "Disassembly method" in the text for the DVD pickup unit.
• Apply solder to the short land sections before the flexible wire is disconnected from the connector CN101 on the DVD servo board.
(If the flexible wire is disconnected without applying solder, the DVD pickup may be destroyed by static electricity.)
• In the assembly, be sure to remove solder from the short land sections after connecting the flexible wire.
Short lands
DVD servo board
Flexible wire CN202
CN201
DVD mechanism assembly
Connector

UX-A7DVD
1-4 (No.22013)
1.8 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 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 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.
CAUTION
Please use enough caution not to see the beam directly
or touch it in case of anadjustment or operation check.
VARNING
Osynlig laserstrålning är denna del är öppnad och spårren är
urkopplad. Betrakta ej strålen.
VARO
Avattaessa ja suojalukitus ohitettaessa olet alttiina näkymät-
tömälle lasersäteilylle. Älä katso säteeseen.
ADVARSEL
Usynlig laserstråling ved åbning, når sikkerhedsafbrydere er
ude af funktion. Undgå udsasttelse for stråling.
ADVARSEL
Usynlig laserstråling ved åpning, når sikkerhetsbryteren er avs-
lott. unngå utsettelse for stråling.
REPRODUCTION AND POSITION OF LABELS
Caution label

UX-A7DVD
(No.22013)1-5
SECTION 2
Disassembly method
2.1 Main body
2.1.1 Removing the metal cover
(See Fig.1~3)
(1) Remove the six screws Aon the back of the body.
(2) Remove the screw Bon each side of the body.
(3) Detach the rear side of the metal cover upward while pull-
ing the lower sides outward.
Fig.1
Fig.2
Fig.3
A
A
A
B
Metal cover
B
Metal cover

UX-A7DVD
1-6 (No.22013)
2.1.2 Removing the DVD mechanism assembly
(See Fig.4, 5)
• Prior to performing the following procedure, remove the metal
cover.
(1) Remove the three screws Cattaching the DVD mecha-
nism assembly on top of the body.
(2) Disconnect connector CN502 and CN503 on the DVD ser-
vo board upward at the bottom of the DVD mechanism as-
sembly.
Bring up the DVD mechanism assembly and remove back-
ward.
Fig.4
Fig.5
CC
C
DVD mechanism assembly
CN502
CN503
DVD mechanism assmbly

UX-A7DVD
(No.22013)1-7
2.1.3 Removing the front panel assembly
(See Fig.6~9)
• Prior to performing the following procedure, remove the metal
cover and the DVD mechanism assembly.
(1) Disconnect the card wire from connector CN705 on the mi-
crocomputer board in the center of the right side of the
body.
(2) Disconnect the card wire from connector CN301,and the
wires from connector CN300 and CN710 on the main
board in the center of the left side of the body.
(3) Disconnect the card wire from connector CN704, and the
wire from CN703 on the microcomputer board.
ATTENTION:
When disconnecting the wires from CN703 and CN710,
remove the spacer attaching the wires.
(4) Disconnect the card wire from connector CN442 on the FL
connection board on top of the body.
(5) Remove the screw Don each side of the body.
(6) Remove the two screws Eon the bottom of the body.
(7) Release the joint aon the bottom and the two joints bon
the right and left sides of the body using a screwdriver. Re-
move the front panel assembly toward the front.
Fig.6
Fig.7
Fig.8
Fig.9
D
Front panel assembly
b
Micro computer board
CN705
D
Front panel assembly
b
Micro computer board
CN704
Main board
CN710
CN301 CN300 CN703
Spacer
CN710
FL connection board
CN442
Space
r
CN703
CN704
D
Front panel assembly
E
a

UX-A7DVD
1-8 (No.22013)
2.1.4 Removing the rear cover / rear panel
(See Fig.10~14)
• Prior to performing the following procedure, remove the metal
cover and the DVD mechanism assembly.
(1) Remove the two screws Fon the back of the body.
REFERENCE:
There is no need to remove the metal cover.
(2) Disconnect the card wire from connector CN1 on the tuner
pack on the right side of the body.
(3) Remove the twelve screws Gand the two screws Hon the
back of the body.
(4) Release the two joints con the lower right and left sides of
the rear panel.
REFERENCE:
The rear panel with the tuner pack comes off.
Fig.10
Fig.11
Fig.12
Fig.13
Fig.14
Rear cover
Rear panel F
Rear panel
Tuner pack
CN1
G
G
G
G
H
Rear cover
Rear panel
c
Rear panel c

UX-A7DVD
(No.22013)1-9
2.1.5 Removing the tuner pack
(See Fig.15)
• Prior to performing the following procedure, remove the metal
cover.
(1) Disconnect the card wire from connector CN1 on the tuner
pack on the right side of the body.
(2) Remove the two screws Ion the back of the body.
Fig.15
2.1.6 Removing the fan
(See Fig.16,17)
• Prior to performing the following procedure, remove the metal
cover, the DVD mechanism assembly, the rear cover/rear pan-
el and the DVD relay board.
(1) Disconnect the wire from connector CN711 on the micro-
computer board on the right side of the body.
(2) Remove the three screws Jattaching the fan bracket on
top of the body and release the joint d.
(3) Remove the two screws Kattaching the fan.
Fig.16
Fig.17
CN1
Tuner pack
I
d
J
J
J
Micro computer board
CN711
Fan bracket
K
Fan bracket
Fan

UX-A7DVD
1-10 (No.22013)
2.1.7 Removing the headphone board
(See Fig.18, 19)
• Prior to performing the following procedure, remove the metal
cover, the DVD mechanism assembly and the front panel as-
sembly.
(1) Disconnect the wire from connector CN310 on the main
board on the left side of the body.
(2) Release the wires from the two clamps on the bottom chas-
sis.
(3) Remove the screw Lattaching the headphone board on
the right side of the body.
Fig.18
Fig.19
Headphone board
Clamp
Main board
CN310
L
Headphone board

UX-A7DVD
(No.22013)1-11
2.1.8 Removing the main board
(See Fig.20, 21)
• Prior to performing the following procedure, remove the metal
cover, the DVD mechanism assembly, the front panel assem-
bly and the rear cover/ rear panel.
(1) Remove the two screws Mand the three screws N, and
then remove the heat sink.
(2) Disconnect the wires from connector CN307 and CN310,
the card wire from CN312 on the main board on the left side
of the body.
(3) Remove the screw Oand Pattaching the main board.
(4) Disconnect connector CN303, CN304, CN305 and CN306
on the main board. Release the two joints eat the bottom.
(5) Draw out the main board and disconnect the wire from con-
nector CN311.
Fig.20
Fig.21
2.1.9 Removing the DVD relay board
(See Fig.22)
• Prior to performing the following procedure, remove the metal
cover, the DVD mechanism assembly and the rear cover/ rear
panel.
(1) Disconnect the card wire from connector CN515 on the
DVD relay board.
(2) Remove the screw Qattaching the DVD relay board on top
of the body.
(3) Disconnect connector CN511 and CN512 on the DVD relay
board.
Fig.22
M
N
Heat sink
Main board
CN303 CN304
CN305
CN306
CN312
CN307
CN310
P
e
e
CN311
O
Q
DVD relay baoard
CN512 CN511
CN515

UX-A7DVD
1-12 (No.22013)
2.1.10 Removing the base chassis / microcomputer board
(See Fig.23~25)
• Prior to performing the following procedure, remove the metal
cover, the DVD mechanism assembly, the front panel assem-
bly, the rear cover/ rear panel, the main board and the DVD re-
lay board.
(1) Disconnect the wires from connector CN701 and CN711
on the microcomputer board in the center of the right side
of the body.
(2) Remove the screw Rattaching the voltage selector board.
(3) Remove the two screws Sattaching the base chassis on
top of the body.
(4) Remove the two screws Tattaching the microcomputer
board and release the two joints f.
Fig.23
Fig.24
Fig.25
Microcomputer board
CN701
Base chassis
CN711
R
Voltage selector board
Base chassis
Fan bracket
S
T
f
Microcomputer
board

UX-A7DVD
(No.22013)1-13
2.1.11 Removing the power transformer assembly
(See Fig.26, 27)
• rior to performing the following procedure, remove the metal
cover, the DVD mechanism assembly, the front panel assem-
bly, the rear cover/ rear panel, the main board and the base
chassis.
(1) Move the power cord stopper upward on the back of the
body and remove. Disconnect the power cord from connec-
tor CN901 on the power transformer board.
REFERENCE:
The power cord can be removed alone.
(2) Remove the four screws Uand release the wires from the
two clamps on the bottom chassis.
Fig.26
Fig.27
Power cord
Power cord stopper
Power amplifier board
Power transformer board
CN901
U
Clamp Bottom chassis
Power transforme
r
assembly
U
U

UX-A7DVD
1-14 (No.22013)
2.1.12 Removiing the power amplifier board
(See Fig.28, 29)
• Prior to performing the following procedure, remove the metal
cover, the DVD mechanism assembly, the front panel assem-
bly, the rear cover/ rear panel, the main board and the base
chassis.
(1) Disconnect the wire from connector CN111 on the power
amplifier board.
(2) Remove the band attaching the wire to the power amplifier
board.
(3) Release the wires from the clamp.
(4) Move the power amplifier board upward to release the two
joints gand remove to the right.
Fig.28
Fig.29
Band Power amplifier board
CN111
Band
g
Clamp
Power amplifier
board

UX-A7DVD
(No.22013)1-15
2.2 Front panel assembly
• Prior to performing the following procedure, remove the metal
cover, the DVD mechanism assembly and the front panel as-
sembly.
2.2.1 Removing the cassette mechanism assembly
(See Fig.30, 31)
(1) Remove the spring attached to the cassette door on the
back of the front panel.
(2) Remove the four screws Vattaching the cassette mecha-
nism assembly.
Fig.30
Fig.31
V
V
V
Spring
Cassette mechanism
assembly
Cassette door
Spring

UX-A7DVD
1-16 (No.22013)
2.2.2 Removing the key board
(See Fig.32~34)
• Prior to performing the following procedure, remove the cas-
sette mechanism assembly.
(1) Pull out the volume knob on the front side of the front panel.
(2) Remove the five screws Wattaching the bracket (1) on the
back of the front panel.
(3) Remove the ten screws Xattaching the key board.
Fig.32
Fig.33
Fig.34
Front panel assembly
Volume knob
WW
W
Bracket(1)
Front panel
X
X
X
X
Key board

UX-A7DVD
(No.22013)1-17
2.2.3 Removing the MIC board
(See Fig.35, 36)
• Prior to performing following procedure, remove the cassette
mechanism assembly
(1) Remove the screw Yattaching the MIC board.
(2) Pull out the mic volume knob on the front side of the front
panel.
Fig.35
Fig.36
Y
Mic volume knob

UX-A7DVD
1-18 (No.22013)
2.2.4 Removing the FL connection board
(See Fig.37~39)
(1) Remove the two screws Zand the screw AA attaching the
bracket (2) on the back of the front panel.
(2) Disconnect the card wire from connector CN441 on the FL
connection board.
(3) Push the two joint tabs hdownward to release and pull out
the FL connection board.
Fig.37
Fig.38
Fig.39
FL connection board
CN441
Front panel
Bracket(2)
Z
Z
Bracket(2)
Front panel
Drive motor assembly AA
FL connection board
CN441
FL connection board
h
h

UX-A7DVD
(No.22013)1-19
2.2.5 Removing the drive motor assembly
(See Fig.37,38,40)
(1) Remove the two screws Zand the screw AA attaching the
bracket (2) on the back of the front panel.
(2) Remove the screw AB attaching the drive motor assem-
bly. Release the joint tab iand pull out the drive motor as-
sembly.
Fig.40
2.2.6 Removing the belt / drive motor
(See Fig.41)
• Prior to performing the following procedure, remove the drive
motor assembly.
(1) Remove the belt from the pulley.
(2) Remove the two screws AC attaching the drive motor.
Fig.41
2.2.7 Removing the switch board.
(See Fig.42)
• Prior to performing the following procedure, remove the brack-
et (2) / drive motor assembly.
(1) Disconnect the card wire from connector CN441 on the FL
connection board (Do not fold down the card wire).
(2) Release the joint jand kin order on the right and left sides
of the shaft gear.
(3) Remove the screw AD attaching the switch board and re-
lease the joint tab k.
Fig.42
AB
i
Drive motor assembly
Belt
Drive motor
AC
AD
kj
Shaft gear
FL connection board
CN441 Switch board
Tab k

UX-A7DVD
1-20 (No.22013)
2.2.8 Removing the FL display section
(See Fig.43~48)
(1) Remove the four screws AE attaching the case cover on
the front panel.
(2) Pull out the FL panel from the four joint bosses mon the FL
display cover.
(3) Remove the four screws AF attaching the FL display cov-
er. Disconnect the card wire from connector CN451 and
CN452 on the FL relay board.
(4) Remove the two screws AG attaching the FL display on
the FL display cover.
(5) The FL board and the lens come off from the FL display
section.
Fig.43
Fig.44
Fig.45
Fig.46
Fig.47
Fig.48
AE
AE
Case cover
m
m
FL panel
A
FAF
FL display cover
FL relay board
CN451 CN452
FL display cover
LED board
CN461
AG AG
FL display section FL display cover
FL board
FL display section
LED board Lens