Jvc UX-G50-E, UX-G50-C Service Manual

SERVICE MANUAL

MICRO COMPONENT SYSTEM

MB50920063

UX-G50J,UX-G50C

CA-UXG50 SP-UXG50SP-UXG50

Lead free solder used in the board (material : Sn-Ag-Cu, melting point : 219 Centigrade)

TABLE OF CONTENTS

1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

2 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

COPYRIGHT © 2006 Victor Company of Japan, Limited

No.MB509

2006/3

SPECIFICATION

Amplifier section Output Power 120 W per channel, min. RMS, driven into 6 Ω at 1 kHz with no more than 10% total har-

monic distortion.

Speakers Impedance 6 Ω - 16 Ω

Audio Input AUX Input sensitivity/Impedance:

LEVEL1:150 mV/47 kΩ
LEVEL2:500 mV/47 kΩ

USB USB Ver. 1.1

Tuner section FM tuning range 87.5 MHz - 108.0 MHz

AM tuning range 530 kHz - 1 710 kHz

CD player section Dynamic range 85 dB

Signal-to-noise ratio 85 dB

Wow and flutter Immeasurable

General Power requirement AC 120 V , 60 Hz

Power consumption 155 W (at operation)

20 W (at standby)

0.8 W (at on standby and Display off)

Dimensions (approx.) 175 mm × 246 mm × 415 mm (6-15/16" × 9-11/16" × 16-3/8") (W/H/D)

Mass (approx.) 7.4 kg (16.4 lbs)

Speakers Type 2-way Bass reflex

Speaker units Woofer 12 cm (4") cone × 1

Tweeter 4 cm (1-5/8") cone × 1
Impedance 6 Ω
Dimensions (approx.) 145 mm × 246 mm × 212 mm (5-3/4" × 9-11/16" × 8-3/8") (W/H/D)

Mass (approx.) 2.2 kg (4.9 lbs) each

Design and specification are subject to change without notice.

1-2 (No.MB509)

SECTION 1

PRECAUTION

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
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 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 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 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, 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, 1,000Ω per volt or more sensitivity
in the following manner. Connect a 1,500Ω 10W resistor
paralleled by a 0.15µF AC-type capacitor between an ex-

posed 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 the chassis, and measure 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.).

AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)

0.15 F AC TYPE

Place this
probe on

1500 10W

Good earth ground

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 pre­forming 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.
(This regulation dose not Except the J and C version)

each exposed
metal part.

(No.MB509)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 laser products.
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.

(caption)
Anti-static wrist strap

1M

Conductive material
(conductive sheet) or iron palate

(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

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) I t 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 pickup unit.

• Apply solder to the short land sections before the flexible wire is disconnected from the connecto on the servo board. (If the flexible
wire is disconnected without applying solder, the 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.

1-4 (No.MB509)

short rand

Pickup board

1.8 Importance administering point on the safety

Full Fuse Replacement Marking

Graphic symbol mark
(This symbol means fast blow type fuse.)

should be read as follows ;

FUSE CAUTION

FOR CONTINUED PROTECTION AGAINST RISK
OF FIRE, REPLACE ONLY WITH SAME TYPE
AND RATING OF FUSES ;

F901 : 3.15A 250V F901 : 3.15A 250V

Marquage Pour Le Remplacement
Complet De Fusible

Le symbole graphique (Ce symbole signifie

fusible de type a fusion rapide.)

^

doit etre interprete comme suit ;

PRECAUTIONS SUR LES FUSIBLES

POUR UNE PROTECTION CONTINUE CONTRE
DES RISQUES D'INCENDIE, REMPLACER
SEULEMENT PAR UN FUSIBLE DU MEME TYPE ;

(No.MB509)1-5

SECTION 2

SPECIFIC SERVICE INSTRUCTIONS

This service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.

1-6 (No.MB509)

SECTION 3

DISASSEMBLY

3.1 Main body

3.1.1 Removing the metal plate
(See Fig.1 and 2)

(1) Remove the six screws A attaching the metal plate from

back side of main body. (See Fig.1)

(2) Remove the four screws B attaching the metal plate from

both side of main body. (See Fig.2)

3.1.2 Removing the top cover
(See Fig.1 and 3)

(1) Remove the one screw C attaching the top cover from back

side of main body. (See Fig.1)

(2) Remove the two screws D attaching the top cover from

both side of main body. (See Fig.3)

(3) Disengage hook a on both side of the front panel. (See

Fig.3)

C

B

A

Fig.1

A

B

Fig.2

D

a

c

Earth wire

P

Fig.3

(No.MB509)1-7

3.1.3 Removing the main board
(See Fig.4)

(1) Remove the two screws E attaching the main board. (See

Fig.4)

(2) Disconnect the card wires connected to connector CN402,

, CN412, CN661 and CN681 of main board.

CN411

(3) Disconnect the connector wire connected to connector

of main board.

CN671

(4) Disconnect the board connector connected connector

and CN601 between amp board and main board.

CN501

CN402 CN671 CN681

3.1.4 Removing the power board
(See Fig.5 and 6)

(1) Remove the two screws F attaching the power board. (See

Fig.5)

(2) Disconnect the power cord connected connector CN901

and power transformer connector wire connected connec­tor CN902

(3) Disconnect the connector wire connected connector

CN102 of amp board.(See Fig.6)

of power board. (See Fig.5)

CN411

EE

CN412 CN661

F

CN601 CN501

Fig.4

CN901

CN902

Fig.5

1-8 (No.MB509)

CN102CN181

Fig.6

3.1.5 Removing the rear plate

(See Fig.7 and 8)

(1) Remove the four screws G attaching the trans cover. (See

Fig.7)

(2) Remove the one screw H attaching the rear plate. (See

Fig.7)

(3) Remove the two screws J attaching the speaker terminal.

(See Fig.7)

(4) Disengage hook b on both side of main chassis. (See

Fig.8)

(5) Disconnect the connector wire from fan connected connec-

tor CN105

3.1.6 Removing the fan

(See Fig.7)

(1) Remove the four screws K attaching the fan.

3.1.7 Removing the tuner pack

(See Fig.7)

(1) Remove the two screws L attaching the tuner pack.

of amp board.(See Fig.8)

L

K

K

J

G

3.1.8 Removing the amp board

(See Fig.6, 8 and 9)

(1) Disconnect the connector wire connected to connector

, CN204, CN205 and CN206 of the amp board. (See

CN181

Fig.6 and 8)

(2) Remove the seven screws M attaching the amp board.

(See Fig.9)

H

G

Fig.7

CN204

CN105

bb

Fig.8

CN206

CN205

M

M

Fig.9

(No.MB509)1-9

3.1.9 Removing the front panel
(See Fig.3 & 10)

(1) Remove the two screws N attaching the front panel assem-

bly. (See Fig.10)

(2) Remove the two screws P attaching the front panel assem-

bly. (See Fig.3)
(3) Disconnect the earth wires from main chassis. (See Fig.3)
(4) Disengage hook c on the both side of main chassis. (See

Fig.3)

3.1.10 Removing the front board
(See Fig.11)

(1) Disconnect the connector wire connected connector

of front board.

CN301

(2) Remove the four screws Q attaching the front board.

3.1.11 Removing the key board
(See Fig.11)

(1) Disconnect the volume knob.
(2) Remove the eleven screws R attaching the key board.

3.1.12 Removing the USB board
(See Fig.11)

(1) Remove the four screws S attaching the USB board.

NN

Fig.10

CN301

Q

Q

R

3.1.13 Removing the power transformer
(See Fig.12)

(1) Remove the four screws T attaching the power transform-

er.

R

S

Fig.11

1-10 (No.MB509)

T

T

Fig.12

3.1.14 Removing the CD mecha cover

(See Fig.13 to 15)

(1) Remove the four screws U attaching the CD mecha cover.

(See Fig.13)

(2) Remove the two screws V attaching the CD mecha holder

F. (See Fig.14)

(3) Remove the two screws W attaching the CD mecha holder

R. (See Fig 15)

U

Fig.13

V

Fig.14

W

Fig.15

(No.MB509)1-11

3.1.15 Removing the CD board
(See Fig.16 to 18)

(1) Disconnect the card wire from connector CN871

board. (See Fig.16)

(2) Disconnect the connector wire connected to connector

and CN873 of CD board. (See Fig.16)

CN872

(3) Disconnect the connector wire from CN702

connected to motor board connector. (See Fig.17)

(4) Remove the four screws X attaching the CD board. (See

Fig.16)

(5) Solder the short land section of the CD pickup. (See

Fig.18)

Caution:

• Solder the short land section of the CD pickup before
disconnecting the card wire from the connector on the
CD pickup. If the card wire id disconnected without at­taching the solders, the pick up may be destroyed by
static electricity.

• When attaching the CD pickup, be sure to remove sol­ders from the short land section after connecting the
card wire to the connector on the CD pickup.

(6) Disconnect the card wire from connector of CD pickup.

(See Fig.18)

of CD

of CD board

CN872CN873

CN702

X

CN871

Fig.16

CN702

Fig.17

Fig.18

short rand

Pickup board

1-12 (No.MB509)

3.1.16 Removing the CD mechanism
(See Fig.19)

(1) Remove the three screws Y attaching the CD mechanism.

YY

Y

Fig.19

(No.MB509)1-13

SECTION 4

ADJUSTMENT

This service manual does not describe ADJUSTMENT.

1-14 (No.MB509)

SECTION 5

TROUBLESHOOTING

This service manual does not describe TROUBLESHOOTING.

(No.MB509)1-15

Victor Company of Japan, Limited
Audio/Video Systems Category 10-1,1chome,Ohwatari-machi,Maebashi-city,371-8543,Japan

(No.MB509)

Printed in Japan

VPT

SCHEMATIC DIAGRAMS

MICRO COMPONENT SYSTEM

UX-G50J,UX-G50C

CD-ROM No.SML200603

Lead free solder used in the board (material : Sn-Ag-Cu, melting point : 219 Centigrade)

Contents

Block diagrams
Standard schematic diagrams
Printed circuit boards

COPYRIGHT 2006 Victor Company of Japan, Limited.

CA-UXG50 SP-UXG50SP-UXG50

2-1

2-3
2-11 to 20

No.MB509SCH

2006/3