JVC MX G50 Service Manual

SERVICE MANUAL

COMPACT COMPONENT SYSTEM

Area Suffix

MX-G50

US UW UY

MX-G50

Singapore

Brazil,Mexico,Peru

Argentina

STANDBY/ON

SUBWOOFER

12

3

SLEEP

LEVEL

456

SOUND

AUX

MODE

78

9

FM MODE

+10

10

zzzzz

ECHO

FADE

TAPE

FM/AM

TAPE A/B

MUTING

DISC SKIP

CD

/

+

VOLUME

–

RM–SMXG50U REMOTE CONTROL

SP-MXG50

(No MIC jack and MIC LEVEL volume for UY ver.)

Contents

Safety Precautions Important for laser products Preventing static electricity Disassembly method Wiring connection Adjustment method

STANDBY

STANDBY/ON

PHONES

COMPU PLAY CONTROL

COMPACT COMPONENT SYSTEM

CLOCK

DISPLAY

/

TIMER

REPEAT PROGRAM

REC START

/STOPCDREC START

EJECT

FULL - LOGIC CONTROL

PLAY

A

1-2 1-3 1-4 1-5 1-20 1-21

DISC CHANGE

PLAY & EXCHANGE

MX-G50

CANCEL /DEMO

TUNING

RANDOM

TAPE A

DUBBING

CD SYNCHRO RECORDING

CD-R/RW PLAYBACK

SOUND

MODE

COMPACT

DIGITAL AUDIO

SUBWOOFER

PRESET

SET

TAPE B

LEVEL

EJECT

REC/PLAY

B

SP-MXG50CA-MXG50

Flow of functional operation until TOC read Maintenance of laser pickup Replacement of laser pickup Trouble shooting Description of major ICs

1-25 1-26 1-26 1-27 1-30~43

No.20978

Jul. 2001

MX-G50

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 perfor m 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 each exposed 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.).

0.15 F AC TYPE

1500 10W

Good earth ground

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

Place this probe on each exposed metal part.

!

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 m ust 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.

In regard with component parts appearing on the silk-screen pr inted 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 J and C version)

1-2

Important for laser products

MX-G50

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.

Reproduction and position of labels

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.

CLASS 1 LASER PRODUCT

WARNING LABEL

1-3

MX-G50

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 CD mechanism assembly is decomposed

*Please refer to "Disassembly method" in the text for pick-up and how to detach the CD mechanism assembly.

1. Remove the CD changer unit.

2. Remove the CD changer mechanism.

3. Solder is put up before the card wire is removed from the pickup unit connector on the CD mechanism assembly. (When the card wire is removed without putting up solder, the CD pick-up assembly might destroy.)

4. Please remove solder after connecting the card wire with the pickup unit connector when you install picking up in the substrate.

Card wire

Pickup unit connector

Soldering

Fig.2

CD changer unit

Fig.1

Card wire

Pickup unit connector

CD changer mechanism

1-4

MX-G50

Disassembly method

Removing the metal cover

(See Fig.1 to 3)

1.

Remove the three screws A attaching the metal cover on the back of the body.

2.

Remove the six screws B attaching the metal cover on both sides of the body.

3.

Remove the metal cover from the body by lifting the rear part of the cover.

ATTENTION:

Do not break the front panel tab fitted to the metal cover.

A

B

A

Fig.1

Metal cover

A

B

Fig.2

Metal cover

Fig.3

B

1-5

MX-G50

Removing the CD Tray fitting (1)

(See Fig. 4 to 6)

Prior to performing the following procedure, remove the metal cover.

1.

Press the POWER button. Press the OPEN/CLOSE button to eject the CD tray.

2.

After drawing the lower part of the tray fitting toward the front, remove the five claws a. Then, while moving the tray fitting upward, remove it.

3.

Press the OPEN/CLOSE button to insert the tray.

Removing the CD Tray fitting (2)

(See Fig. 5 to 7)

POWER button

CD tray fitting

CD tray

OPEN/CLOSE button

Fig.4

Joint

- How to eject the CD tray without turning on power -

1.

Turn the black loading pulley gear marked b from the back of the CD changer unit as shown in Fig.7 and draw the CD tray toward the front.

2.

After drawing the lower part of the tray fitting toward the front, remove the five claws a. Then, while moving the tray fitting upward, remove it.

3.

Push and insert the CD tray manually.

(See Fig. 24)

Claw a

Fig.5

CD tray

(Loading pulley gear)

b

1-6

This slot of the board.

Fig.7

Fig.6

MX-G50

Removing the CD changer unit

(See Fig.8 to 10)

Prior to performing the following procedure, remove the metal cover.

1.

Disconnect the card wire which is attached with adhesive to the left side of the CD changer unit.

2.

Disconnect the card wire from connector CW105 of the CD servo board on the back of the CD changer unit.

3.

Disconnect the harness from connector RCW6 & OCW on the inner side of the main board in the body.

4.

Remove the two screws C attaching the CD changer unit on the back of the body.

5.

Remove the two screws D attaching the CD changer unit on the both side of the body.

CD servo board

CW105

Main board

CD changer unit

OCW

RCW6

Fig.8

C

6.

Draw the CD changer unit upward from behind while pulling the rear panel outward.

Adhesive card wire strap

CD changer unit

D

Rear panel

Fig.9

CD changer unit

D

Rear panel

Fig.10 aFig.10 b

Front panel assembly

1-7

MX-G50

Removing the front panel assembly

(See Fig.11 to 13)

Prior to performing the following procedure, remove the metal cover and the CD changer unit.

1.

Disconnect the card wire from connector FCW3 and the harness from connector JCW1, JCW2 and HCW3 on the inner side of the main board in the body.

2.

Remove the two screws E attaching the front panel assembly on both sides of the body.

3.

Remove the screw F attaching the earth terminal extending from the cassette mechanism assembly.

4.

Remove the screw G attaching the front panel assembly and main board.

5.

Remove the screw H attaching the front panel assembly on the bottom of the body.

6.

Release the two joints c on both sides and two joints d on the bottom of the body using a screwdriver.

Front panel assembly

Joint c

E

earth wire

Main board

FCW3

JCW2

F

Fig.11

Main board

JCW1

ACW1

ACW2

HCW3

Front panel assembly

Bottom side

Joint d

Fig.12

H

E

G

Joint c

Joint d

1-8

Fig.13

Removing the heat sink & amp. board

(See Fig.14 and 15)

Prior to performing the following procedure, remove the metal cover and the CD changer unit.

1.

Remove the four screws I attaching the heat sink cover on the back of the body. Remove the heat sink cover.

2.

Remove the four screws J attaching the heat sink & amp. board to the rear panel on the back of the body.

3.

Remove the two screws K attaching the speaker terminal to the rear panel on the back of the body.

4.

Disconnect the card wire from connector ACW1 and the harness from connector ACW2 on the amp. board. (See Fig.11)

I

Heat sink

cover

I

Rear panel

Fig.14

MX-G50

Tuner terminal

5.

After moving the heat sink upward, remove the claws. Then pull out the heat sink & AMP board inward.

Removing the tuner board

(See Fig.15 and 16)

Prior to performing the following procedure, remove the metal cover and CD changer unit.

1.

Disconnect the card wire from connector CON01 on the tuner board.

2.

Remove the two screws L attaching the tuner board.

Removing the rear cover (See Fig.17)

Prior to performing the following procedure, remove the metal cover, CD changer unit, heat sink & amp. board and tuner board.

1.

Remove the five screws M attaching the rear panel.

2.

Remove the screw M' attaching the voltage selector. (Only US/ UW)

J

L

Heat sink

K

J

Speaker terminal

Fig.15

Main board

CON01

Fig.17

M'

M

Fig.16

Tuner board

1-9

MX-G50

Removing the main board

(See Fig. 18)

Prior to performing the following procedure, remove the metal cover, CD changer unit, heat sink & amp. board tuner board and rear cover.

1.

Disconnect the card wire from connector FCW3 and the harness from connector JCW1, JCW2 and HCW3 on the main board.

2.

Disconnect the harness from connector PCW1 on the power transformer board.

3.

Remove the screw G attaching the main board holder. (See Fig.12)

4.

Remove the two screws N attaching the heat sink and bottom chassis.

Removing the power ICs

(See Fig.19 and 20)

Prior to performing the following procedure, remove the metal cover, CD changer unit and heat sink & amp. board.

PCW1

Transformer board

FCW3

JCW2

Fig.18

Heat sink

JCW1

N

HCW3

Main board

P

1.

Remove the four screws P attaching the power ICs to the heat sink.

2.

Unsolder the power ICs solder point.

Removing the power transformer

(See Fig .21)

Prior to performing the following procedure, remove the metal cover, heat sink & amp. board, tuner board and rear cover.

1.

Disconnect the power cord from connector RCW2 of the power transformer board.

2.

Disconnect the harness from connector PCW1 of the power transformer board.

3.

Remove the four screws R attaching the power transformer and the screw S attaching the earth terminal.

Power ICs solder point

Power transformer

Fig.19

Fig.20

Amp. board

Heat sink

PCW1

1-10

RCW2

R

Power cord

R

Fig.21

MX-G50

Prior to performing the following procedure, remove the metal cover, the CD changer unit and the front panel assembly.

Removing the power / CD switch board

(See Fig.22)

1.

Disconnect the card wire from connector UCW1 on the power / CD switch board.

2.

Remove the five screws Q attaching the power / CD switch board.

Removing the FL display & system control board (See Fig.22)

1.

Disconnect the card wire from the connector UCW3, UCW4,UCW5 and UCW6 on the FL display & system control board.

2.

Remove the five screws R attaching the FL display & system control board.

3.

Disconnect the card wire from the connector UCW2 on the FL display & system control board.

Power / CD switch board

UCW2 UCW3 UCW4

R

UCW1

Q

R

FL display & system

control board

R

UCW5

UCW6

Fig.22

SOUND MODE knob ACTIVE BASS EX.

LEVEL knob VOLUME knob

MIC LEVEL knob (Only US/ UW)

Removing the front board

(See Fig.23 and 24)

Prior to performing the following procedure, remove the FL display & system control board.

1.

Pull out the SOUND MODE knob, ACTIVE BASS EX. LEVEL knob, VOLUME knob and MIC LEVEL knob(Only US/ UW) from front side.

2.

Remove the ten screws S attaching the front board and release the two tabs e out ward.

Removing the headphone board & mic jack board (See Fig.24)

Prior to performing the following procedure remove the FL display & system control board.

1.

You can pull out the headphone board.

2.

Remove the mic jack board with releasing the tab f. (Only US/ UW)

Removing the cassette mechanism assembly (See Fig.24)

Front board

Tab e

Mic jack board (Only US/ UW)

Tab f

S

Fig.23

S

Headphone board

S

T

Card wire x

Cassette mechanism assembly

Fig.24

1.

Disconnect the card wire x from the mechanism board on the cassette mechanism assembly.

2.

Remove the six screws T attaching the cassette mechanism assembly.

1-11

MX-G50

Prior to performing the following procedure, remove the CD changer unit.

Removing the CD tray (See Fig.25 to 27)

1.

Turn the black loading pulley gear on the under side of the CD changer unit in the direction of the arrow and draw the CD tray toward the front until it stops.

2.

Disconnect the card wire from connector CW103 of the CD servo board on the upper side of the CD changer unit.

Loading pulley gear

CD tray

Fig.25

3.

Push down the two tray stoppers marked g and pull out the CD tray.

Reinstall the CD tray (See Fig.28 to 29)

1.

Align the gear-cam with the gear-tray as shown fig.27, then mount the CD tray.

2.

When assembling the CD tray, take extreme care not engage with gear - synchro.

CD tray

Fig.26

g (Tray stopper)

CD tray

g

(Tray stopper)

CD servo board

CW103

Fig.27

Gear-cam

Gear-convert

1-12

Gear-tray

Gear-cam

timing point

Gear-tray

CD tray

Fig.28 Fig.29

Gear-synchro

Removing the sensor board / the turn table motor assembly (See Fig.30 to 32)

Prior to performing the following procedure, remove the CD tray.

MX-G50

X

1.

Remove the screw X attaching the sensor board and release the two tabs h attaching the sensor board on the under side of the CD tray.

2.

Disconnect the harness from connector CW1 on the sensor board and release the harness from the two hooks i. Remove the sensor board.

3.

Remove the screw Y attaching the turn table. Detach the turn table from the tray.

4.

Pull outward the tab marked j attaching the turn table motor assembly on the upper side of the tray and detach the turn table motor assembly from the tray.

Tray

h

CW1

i

h

Sensor board

Fig.29

Turn table

Y

Turn table motor assembly

Fig.31

j

Fig.32

1-13

MX-G50

Removing the belt, the CD servo board and the switch board (See Fig.33 and 34)

Prior to performing the following procedure, remove the CD tray.

1.

Detach the belt from the pulley on the upper side of the CD changer unit (Do not stain the belt with grease).

2.

Disconnect the card wire from the pickup unit connector on the under side of the CD changer unit.

Attention : Solder is put up before the card wire is removed from the pick-up unit connector on the CD mechanism assembly. (When the card wire is removed without putting up solder, the CD pick-up unit assembly might destroy.)

3.

Disconnect the motor wire harness from connector on the CD servo board.

4.

Remove the screw Z attaching the switch board and release the two tabs k attaching the switch board outward and detach the switch board.

5.

Remove the two screws A' attaching the CD servo board and . First release the n side of the two tabs l and two tabs m attaching the CD servo board motor to raise the CD servo board slightly, then release the CD servo board.

Tabs k

Z

Switch board

CW3

CD changer unit

Fig.33

A'

CD servo board

Tabs m

Soldered points

Pickup unit connector

Belt

Motor

Tabs l

CD mechanism board

motor connecter

If the tabs l and m are hard to release, it is recommendable to unsolder the two soldered points on the motor terminal of the CD servo board.

Soldering

Card wire

Picup unit connector

Fig.34

1-14

Removing the CD mechanism holder assembly (mechanism included)

(See Fig.35 to 38)

1.

Disconnect the harness from connector on the CD mechanism board in the CD mechanism assembly on the under side of the CD changer unit. Disconnect the card wire from the pickup unit connector.

Attention : Solder is put up before the card wire is removed from the pick-up unit connector on the CD mechanism assembly. (Refer to Fig. 34) (When the card wire is removed without putting up solder, the CD pick-up unit assembly might destroy.)

MX-G50

Motor connecter

CD changer unit

CD mechanism holder assembly

Pickup unit connector

2.

Remove the screw B' attaching the shaft on the right side of the CD mechanism holder assembly. Pull outward the stopper fixing the shaft on the left side and remove the CD mechanism holder assembly from behind in the direction of the arrow y.

3.

Turn the CD mechanism holder assembly half around the lift up slide shaft n of the CD mechanism holder assembly until the turn table is reversed, and pull out the CD mechanism holder assembly.

Lift up slide shaft

Fig.35

B'

Stopper

CD mechanism holder assembly

Fig.36

Lift up slide shaft n

CD mechanism holder assembly

Fig.38

y

CD mechanism holder assembly

Fig.37

1-15

MX-G50

•

Removing the CD mechanism holder from the CD chager unit. (Refer to "Removing the CD mechanism holder assembly" )

Removing the pickup unit. (

1. Removing the cut washer c on the feed gear sleeve and pull out the feed gear.

2. Remove the two screws A fixing the pickup shaft.

3. Removing the pickup unit.

Removing the motor board.

1. Unsolder the motor terminal on the motor board.

2. Remove the moter board.

Removing the feed motor. (

Remove the two motor fixing screws at B and removing the feed motor.

Removing the spindle motor.

The spindle motor cannot be removed as a single unit. When removing the spindle motor, change the chasis and turntable together as aunit.

See Fig.1)

(See Fig.2)

See Fig.1)

A

Motor board

Shutter

Cut washer

B

Fig.1

Unsolder

Shaft

Pickup unit

A

Feed Gear

Feed motor

Spindle motor

Unsolder

Fig.2

1-16

MX-G50

Removing the record/playback mechanism.

Removing the R/P head.

1. Remove the screw A on the right side of the R/P head.(Fig.1, Fig.2)

2. Remove the screw B on the left side of the R/P head.(Fig.1, Fig.2)

Remove the erase head.

Remove the screw C fixing the erase head.(Fig.1)

Removing the pinch roller.

1. Pull out the pinch roller by opening the pinch roller stopper outward to unlock .(Fig.3)

2. When reassembling the pinch roller, refer to fig. 4 to hook up the spring.

R/P Head

E. Head

Stoppsr

A

B

C

Fig.1

B

Pinch roller assembly

A

Spring

Pinch roller

Return spring

R/P Head

Fig.2

Pinch roller

stopper

Fig.3

Pinch roller

spring

Return spring

Fig.4

1-17

MX-G50

Removing the motor.

1. Remove the two screws D fixing the motor. Be careful to grease's splash when the

drive belt comes off.(Fig.5, Fig.6)

2. Unsolder the motor terminal.(Fig.5)

Removing the mechanism board.

1.

coil terminal.(Fig.5)

2. Remove the two screws E fixing the board.(Fig.5)

Removing the flywheel.

capstan shaft, then remove the flywheel. When reassembling the flywheel, be sure to use new washers as they cannot be reused.(Fig.8, Fig.9)

Unsolder the four parts a on the solenoid

3. Unhook the three parts b from the board.(Fig.5)

4. Remove the mechanism board.(Fig.5)

Remove the cut-washers at c and d from the

Mecha.

a

Drive belt (Flat)

board

E

b

Motor

terminal

D

Fig.5

Drive belt

Fig.6

E

Drive belt

Motor

b

a

1-18

Sleeve

Flywheel

c

Washer

Sleeve

d

FR belt

Capstan

washer

Flywheel

Fig.7

FR belt

Fig.8Fig.9

Capstan

washer

Flywheel

MX-G50

< Speaker section >

Removing the side panel (See Fig. 1)

1.

Remove the five screws A attaching the side panel, then remove the side panel.

Removing the side speaker

(See Fig. 2 and 3)

Prior to performing the following procedure, remove the side panel.

B

Side panel

A

B

Fig.1

Side speaker

C

Front panel

1.

Remove the fore screws C attaching the side speaker.

2.

Pull out the side speaker and remove the speaker cord from the speaker terminal.

C

Fig.2

Side speaker

Speaker terminal

Fig.3

1-19

MX-G50

Wiring connection

Amp board

0

ACW2

ACW1

3809-001224

CD key switch board

UCW1

9

UCW7

Front key switch board

0

9 0

AH39-00254A

UCW2

Front / Display board

RCW2

Power transformer

PCW1

UCW3

RFS5

RFS6

UCW4

RFS2

RFS7

RFS8

UCW6

UCW5

AH39-20561P

3809-001121

CD mechanism

CW2

CW1

CW3

0

3809-001185

Color codes are shown below. 1 Brown

2 Red 3 Orange 4 Yellow 5 Green 6 Blue

9

8Gray

7 Violet

0

9 White 0 Black

AAN1

0

2

0

2

16634-502-610

CW102

CW103

9

CW105

CW107

CW101

CW3

CW106

CW104

3809-001034

2

0

9

0

AH39-20025S

AH39-00096D

1-20

3809-001228

3708-000258

3708-000122

0

9

2

9

0

9

0

FCW1

OCW

9

0

RCW6

FCW2

Main board

Tuner board

HCW3

JW1

JCW1

FCW3

JCW2

FCW3

0

9

RW2

9

0

9

0

9

RW1

2

0

9

0

HCW2

AH39-00247A

9

E.phone J.board

AH39-00022A

Cassette mechanism

9

0

9

0

2

88

9

2

0

AH39-20002D

8

2

8

2

Adjustment method

1. Tuner

MX-G50

ITEAM

Received FREQ. Adjustment

point

Output

* Adjustment Location of Tuner PCB

AM(MW) OSC Adjustment

522~1611 KHz

MO

1~7.0 0.5V

MAIN PCB

AM(MW) RF Adjustment

594 KHz

MA

Maximum Output(Fig1-4)

VT GND

Fig 1-4 OSC Voltage

TESTER

1-21

MX-G50

FM THD Adjustment

SSG FREQ.

98 MHz

Adjustment point

FM DETECTOR COIL

(FM DET)

Output

60 dB

Minimum Distortion (0.4% below) (Figure 1-1)

FM Search Level Adjustment

SSG FREQ. Adjustment

point

(SVR1)

Output

BEACON SENSITIVITY SEMI-VR(20K )

28 dB(

98 MHz

2dB)

Output GND

FM S.S.G

FM Antenna Terminal

Speaker Terminal

SET

Input

output

Distortion Meter

Figure1-1 IF CENTER and THD Adjustment

FM Antenna

SET

FM IN

FM S.S.G

28 dB

GND

Oscilloscope

Input

Adjust SVR1 so that "TUNED" of FL T is lighted (Figure 1-2)

*Adjust FM S.S.G level to 28dB

AM(MW) I.F Adjustment

SSG FREQ. Frequency

450 kHz 522 kHz

Adjustment point

AM IF

Maximum output (Figure 1-3)

Figure1-2 FM Auto Search Level Adjustment

60cm

OUTPUT

AM SSG 450KHZ

INPUT

AM ANT IN

Speaker Terminal

OUTPUT

VTVM Oscilloscope

Figure1-3 AM I.F Adjustment

20 k

AM IF

1-22

2 Cassette Deck

To adjust tape speed

MX-G50

Notes

1) Measuring tape: i) VT-712(or equivalent) (Tapes recorded with 3kHz)

ii) AC-225(or equivalent)

2) Connect the cassette deck to the frequency counter

as in figure 1-5.

Step

Item

Pre-Setup Condition

Pre-Setup

1) Deck A:VT-712

NOR

1

SPEED Control

Recording /Play head

OUT (connected to the frequency counter)

2) Press PLAY SW button

3) Deck B:Same as above

Cassette Deck

SPK OUT

To Adjust

Turn VSR1 to left and right (FRONT PCB)

Cassette Deck

SPK OUT

Figure 1-5

VTVM

Frequency Counter

Standard

3KHz

Oscilloscope

output

Remark

1%

range

AZIMUTH control screw

Figure 1-6

Audio OSC.

SET (MAIN PCB)

IN

AUX IN

LINE OUT

TP

JCW3

Figure 1-8

VTVM

IN OUT

(GND)

In Out

Figure 1-7

Oscilloscope

1-23

MX-G50

To adjust plabyback level/REC

Notes

1) Before the actual adjustment, clean the play/recording head.

2) Measuring tape : i) VT-703(or equivalent 10kHz AZIMUTH control)

ii) AC-225(or equivalent)

3) The cassette deck is connections as shown in figure 1-7.

1. Adjust Deck A Play Level

Step

1

Item

AZIMUTH

Pre-Setup Condition

SPK OUT (VTVM is connected to

Pre-Setup

After putting VT703 into Deck A

- Press FWD PLAY button.

the scope)

2. Adjust Deck B Play Level/REC BIAS

Step

1

Item

AZIMUTH

Pre-Setup Condition

SPK OUT (VTVM is connected to the scope)

Pre-Setup

After putting VT-703 into Deck B

1)Press FWD PLAY button.

To Adjust

- Turn the control screw to as shown in Figure 1-6.

To Adjust

- Turn the control screw to as shown in Figure 1-6.

Standard

Max output and same phase (both channels)

Standard

Max output and same phase (both channels)

Remark

After adjustment secure it with REGION LOCK.

Remark

After adjustment secure it with REGION LOCK.

1-24

2

Recording Bias Voltage

Fig 1-8

After putting AC-225

into Deck B

1)Press REC PLAY button.

2)MAIN PCB JCW3, connectted to VTVM

Turn JSR2L,JSR2R

to the right and left

7mV(

0.5

mV)

Flow of functional operation until TOC read

Power ON

Play Key

RESET a CD LSI

Confirm that the voltage at the pin17 of KB9226(IC101) is "L" "H".

MX-G50

Check Point

LIMIT SW ON

SET Default value of TE gain, TE balance

Automatic adjusting of

focus bias

Automatic adjusting of

FE offset

Automatic adjusting of

TE offset

LASER power ON

Detection of disk

Confirm that the voltage at the pin33 of KB9226(IC101) is "H" "L" "H".

Confirm that the voltage at the pin37 of KB9226(IC101) is 3.5V.

Tracking error waveform at TOC reading

Pin 34 of KB9226 (IC101)

2.50V

Approx

0.4V

Disc states to rotate

Approx.3.7sec

Disc is rotated

Automatic adjusting of

TE balance

Automatic adjusting of

TE gain

TOC reading

Play a disc

Confirm that the signal from pin24 of KB9226(IC101) is 3.5V as a accelerated pulse during approx.1.96s.

Confirm the waveform of the Tracking error signal at the pin 34 of KB9226(IC101).

Confirm the eye-pattern at the pin2 of KB9226(IC101).

1-25

MX-G50

Maintenance of laser pickup

(1) Cleaning the pick up lens Before you replace the pick up, please try to clean the lens with a alcohol soaked cotton swab.

(2) Life of the laser diode When the life of the laser diode has expired, the following symptoms will appear.

1. The level of RF output (EFM output:ampli tude of eye pattern) will below.

Is the level of

RFOUT under

1.1V 0.2Vp-p?

YES

O.K

NO

Replace it.

Replacement of laser pickup

Turn off the power switch and,disconnect the power cord from the ac outlet.

Replace the pickup with a normal one.(Refer to "Pickup Removal" on the previous page)

Plug the power cord in,and turn the power on. At this time,check that the laser emits for about 3seconds and the objective lens moves up and down. Note: Do not observe the laser beam directly.

Play a disc.

(3)

Semi-fixed resistor on the APC PC board The semi-fixed resistor on the APC printed circuit board which is attached to the pickup is used to adjust the laser power. Since this adjustment should be performed to match the characteristics of the whole optical block, do not touch the semi-fixed resistor. If the laser power is lower than the specified value, the laser diode is almost worn out, and the laser pickup should be replaced. If the semi-fixed resistor is adjusted while the pickup is functioning normally,the laser pickup may be damaged due to excessive current.

Check the eye-pattern at TP1.

Finish.

1-26

Troubleshooting

1. Amplifier

Power malfunction

MX-G50

Front PCB -com VDD(5V) normal?

UIC1 pin no.18, 46,90

Yes

Front PCB

Does UX1(6MHz)

oscillate?

Yes

Front PCB

When the power is

ON 'H' display at pin

no.15(UIC2)

Yes

Check the main PCB

RIC1(L4959)

No

Main PCB RIC1(L4959)

pin No.2, 10 input

voltage normal?

-Check the main PCB RIC1(L4959)

-Check the front PCB UD13(IN4002)

Front PCB PWR-SENS

voltage normal?

No

Replase UIC2(M66010)

(pin no.94;5V)

Yes

Replase -com

No

-Check the main PCB; RBD1(PBL403) RD8(IN5392)

-Check the power PCB; Fuse P/T, RFS2, RFS5, RFS6

No

-Check the main PCB; RR7, RC7, RZD4, RR6 RR5, RR4, RC8, RD3

No output

AMP PCB AIC1,

AQ2L, 2R, AQ1,2,3,4

Is mute selected?

Headphone jack short?

UIC1( -com)pin79

check the "H"?

pin no. 4,8,9,12

B+,B- normal?

Yes

Emitter B+?

Yes

No

Yes

Check the B+, B- power source RBD1, RBD2, RW2 Check the power PCB Fuse, P/T, RFS2, RFS5, RFS6, RFS7, RFS8

Check the AMP PCB AIC1, AIC2

Remove it with remocon

Check headphone jack soldering condition

Check the front PCB UIC( -com), UIC2(M66010GP)

No

Check the AMP PCB AQ2L, 2R, AQ1,5,6,7

1-27

MX-G50

2. Tuner malfunction (FM/AM)

3. Tape malfunction

1-28

4.CD

MX-G50

1-29

MX-G50

Description of major ICs

5L9290 (IC201) : Digital signal processor for CDP

1. Pin layout

VSSA_DAC

VREF

VHALF

VDDA_DAC

LRHOUT

VDDA_PLL

48 47 46 45 44 43 42 41 40 39 38 37

VDDD_DAC

RCHOUT

SADTI

VSSD_DAC

LRCKI

BCKI

2. Block diagram

VSSA_PLL

VCO1LF

VSSD_PLL

VDDD_PLL

VDDD1_5V

XIN

XOUT

VSSD1_5V

EFMI

LOCK

SMEF

SMON

1

2

3

4

5

6

7

8

9

10

11

12

13 14 15 16 17 18 19 20 21 22 23 24

SMDS

WDCK

S5L9290X

DSP+DAC

48-LQFP-0707

LKFS

TESTV

LKFS

RESETB

MLT

MDAT

SOS1

SQCK

SBCK

SQDT SBDT

MCK

ISTAT

S0S1

C2PO DATX

SQCK

36

35

34

33

32

31

30

29

28

27

26

25

BCKO

LRCKO

SADTO

DATX

C2PO

JITB

SBCK

VDDD3-5V

VSSD2-3V

VDDD2-3V

MUTE

SQDT

1-30

VCO1LF

EFMI

LOCK

SMEF SMDP SMDS

WDCK

WFCK

RFCK

C4M

XIN

ISTAT

MLT

MDAT

MCK

MUTE

DPLL

CLV

Servo

Timing

Generator

Micom

Interface

Subcode

Out

EFM

Demodulator

ECC

16K

SRAM

Address

Generator

JITB

Interpolator

Interface

SADTO LRCKO

BCKO

I/O

Digital

Out

SADTI LRCKI

BCKI

Digital

Filter

1-bit

DAC

PWM

LPF

LCHOUT

RCHOUT

VHALF

VREF

MX-G50

3. Pin function

NO. NAME I/O Pin Description

1 VSSA_PLL - Analog Ground for DPLL 2 VCO1LF O Pump out for VCO1 3 VSSD_PLL - Digital Ground Separated Bulk Bias for DPLL 4 VDDD_PLL - Digital Power Separated Bulk Bias for DPLL (3V Power) 5 VDDD1-5V - Digital Power (5V Power, I/O PAD) 6 XIN I X'tal oscillator input (16.9344MHz) 7 XOUT O X'tal oscillator output 8 VSSD1 - Digital Ground (I/O PAD)

9 EFMI I EFM signal input 10 LOCK O CLV Servo locking status output 11 SMEF O LPF time constant control of the spindle servo error signal 12 SMDP O Phase control output for Spindle Motor drive 13 SMDS O Speed control output for Spindle Motor drive 14 WDCK O Word clock output (Normal Speed : 88.2KHz, Double Speed : 176.4KHz)

(1/2)

15 TESTV I Various Data/Clock Input 16 LKFS O The Lock status output of frame sync 17 C4M O 4.2336MHz clock output 18 RESETB I System Reset at 'L' 19 MLT I Latch signal input from Micom 20 MDAT I Serial data input from Micom 21 MCK I Serial data receiving clock input from Micom 22 ISTAT O The internal status output to Micom 23 S0S1 O Subcode sync signal(S0+S1) output 24 SQCK I Subcode-Q data transfering bit clock input

1-31

MX-G50

3. Pin function

NO. NAME I/O Function Description

25 SQDT O Subcode-Q data serial output 26 MUTE I System mute at 'H' 27 VDDD2-3V - Digital Power (3V Power, Internal Logic) 28 VSSD2 - Digital Ground (Internal Logic) 28 VDDD3-5V - Digital Power (5V Power, I/O PAD) 30 SBCK I Subcode data transfering bit clock 31 JITB O Internal SRAM jitter margin status output 32 C2PO O C2 pointer output 33 DATX O Digital audio data output 34 SADTO O Serial audio data output (48 slot, MSB first) 35 LRCKO O Channel clock output 36 BCKO O Bit clock output 37 BCKI I Bit clock input 38 LRCKI I Channel clock input

(2/2)

39 SADTI I Serial audio data input (48 slot, MSB first) 40 VSSD_DAC - Digital Ground for DAC 41 VDDD_DAC - Digital Power for DAC (3V Power) 42 RCHOUT O Right-Channel audio output through DAC 43 VSSA_DAC - Analog Ground for DAC 44 VREF O Referance Voltage output for bypass 45 VHALF O Referance Voltage output for bypass 46 VDDA_DAC - Analog Power for DAC (3V Power) 47 LCHOUT O Left-Channel audio output through DAC 48 VDDA_PLL - Analog Power for PLL (3V Power)

1-32

BA4560 (AIC3, AIC4, AIC5, AIC6, AIC7, FIC4, JIC2, UIC3) : Op amp.

1.Pin layout

MX-G50

OUT1

– IN1

+ IN1

1

2

1ch

+

–

3

EE

V

4

2ch

+

V

CC

8

OUT2

7

– IN2

6

–

+ IN2

5

KA9258D (IC301) : 4-ch Motor driver

28 27 26 25 24 23 22 21 20 19 18 17 16 15

10K

VCC VCC

10K

GND

10K

T • S • D

10K

+-

LEVEL SHIFT

REGULATOR

10K

50K

MUTE

LEVEL SHIFT

-+

10K

1 2 3 4 5 6 7 8 9 10 11 12 13 14

GND

1-33

MX-G50

KA22291(JIC1) : PB/REC pre amp.

1.Pin layout

KA22291

1 2 3 4 5 6 7 8 9 101112

2.Block diagram

131415161718192021222324

PB OUT(2)

Vcc

REC GND

PB OUT(1)

24

16

17

9

1

PB NF(2) PB IN(2) R/P SW SW IN(2) ALC OUT(2)

22 21 8 20

B-IN

A-AN

MODE CONTROL

B-IN

/BIAS CIRCUIT

A-AN

PB.BIAS

INPUT

100k

PRE

RECORE

I.REF

PLAYBACK

I.REF

PRE

100k

23

INPUT

REC.BIAS

N.F

PB NF(1) PB IN(1) A/B SW PB MUTE REC

MUTE MUTE REC

19

R/P SW

A/B SELECT SW

GND IN(1) OUT(1)

18

15

ALC TIME CONSTANT

102 3 4 5 7 6

ALC DET

100k

PRE

100k

NF

INPUT

N.F

14

13

12

11

REC NF(2)

REC IN(2)

REC IN(1)

REC NF(1)

1-34

KA3082 (IC401, IC402) : Bi-directional DC motor driver

1.Pin layout

KA3082

MX-G50

GND V

12345678910

O1

V

Z1

CTLVIN1

V

IN2

SV

CC

PV

CCVZ2

2.Pin function

Pin Number Pin Name I/O Pin Function Descriptio n

1 GND - Ground 2V 3V 4V 5V 6V 7SV 8PV 9V

10 V

O1

Z1

CTL

IN1 IN2

CC CC

Z2

O2

O Output 1

- Phase compensation I Motor speed control I Input 1 I Input 2

- Supply voltage (Signal)

- Supply voltage (Power)

- Phase compensation

O Output 2

V

O2

3.Block Diagram

BIAS

1234

GND

O1

V

Z1

V

CTL

DRIVER OUT

PRE DRIVER

LOGIC SWITCH

5

V

IN1

678910

V

IN2

SV

CC

TSD

PV

CC

Z2

V

O2

V

1-35

MX-G50

KB9226 (IC101) :

1. Pin layout

2. Block diagram

RF amp & Servo signal processor

36 35 34 33 32 31 30 29 28 27 26 25

SLP

37

LD PD

38 39

PDAC PDBD

40

PDF

41

PDE

42

DCB

43

MCP

44

DCCI

45

DCCO

46

VREF

47

EQC

48

LPFT

ATSC

RFO

RFM

1 2 3 4 5 6 7 8 9 10 11 12

TEIO

TZC/SSTOP

S1L9226X

EQO

EQI

GND

EFMI

FEO

VCC

FEM

FRSH

TEO

FSET

TEM

FLB

FGD

SLO

FSI

SLM

SPO

SPM

ASY EFM

LOCK

WDCK

CLVI

RESET

MLT

MDATA

MCK

ISTAT

TGU

24 23 22 21 20 19 18 17 16 15 14 13

EQO

EFMI DCCI

DCC0

MCP

DCB

VCC/

VDD

FRSH

FSET

FLB

FGD

FSI

45 46 44 43

10

11

EQI

RFO

RFM

4

5

RF AGC & EQ

Control

Focus OK Detect

Defect Detect Mirror

Gen

Focus Servo Loop

- Gain & Phase Compensation

- Focus Search

- Offset Adjust

- FZC Gen.

6 7 8 9

EQC

Center

Voltage

APC. Laser

Control &

LPC

Tracking Servo Loop

- Gain & Phase Compensation

- Track Jump

- Offset Adjust

- TZC Gen.

Hardware Logic

- Auto-Sequencer

- Fast Search

- Febias, Focus Servo, Tracking Offset ADJ.

VREF

PDE

41 40424748123

Tracking Error

(RW)

I/V AMP

PDF

PDBD

39

RF & Focus

Error (CD-RW)

I/V AMP

Sled Servo &

Kick Gen

PDAC

38 37

35 34

33 36

29 28

27 26 25

PD LD

LPFT TEIO

TZC& SSTOP

ATSC

TEO TEM

SLP SLO SLM

- Tracking Balance & Gain Adjust

- Interruption Detect

29

FEO

- EFM Muting System 30

FEM

1-36

TGU

12

Micom Data Interface Logic Decoder

Comparator

1413 15 16 17 19 18 20 22 21

ISTAT

MCK

MDATA

MLT

RESET

WDCK

CLVI

LOCK

EFM

ASY

EFM

Spindle

Servo LPF

23

24

SPDLO

SPDLM

MX-G50

3. Pin function

Pin No. Symbol I/O Description

1 R FM I RF summing amp. inverting input 2 RFO O RF summing amp. output 3 EQI I RFO DC eliminating input(use by MIRROR, FOK ,AGC & EQ terminal) 4 EQO O RF equalizer output 5 EFMI I EFM slice input. (input impedance 47K) 6 VCC P Main power supply 7 FRSH I Capcitor connection to focus search 8 FSET I Filter bias for focus,tracking,spindle

9 FLB I Capacitor connection to make focus loop rising band 10 FGD I Terminal to change the hign frequency gain of focus loop 11 FSI I Focus servo input 12 TGU I Connect the component to change the high frequency of tracking Loop 13 ISTAT O Internal status output 14 MCK I Micom clock 15 MDATA I Data input

(1/2)

16 MLT I Data latch input 17 RESET I Reset input 18 CLVI I Input the spindle control output from DSP 19 WDCK I 88.2KHz input terminal from DSP 20 LOCK I Sled run away inhibit pin (L: sled off & tracking gain up) 21 EFM O EFM output for RFO slice(to DSP) 22 ASY I Auto asymmetry control input 23 SPM I Spindle amp. inverting input 24 SPO O Spindle amp. output 25 SLM I Sled servo inverting input 26 SLO O Sled servo output 27 SLP I Sled servo noninverting input 28 TEM I Tracking servo amp.inverting input 29 TEO O Tracking servo amp. output 30 FEM I Focus servo amp. inverting input 31 FEO O Focus servo amp. output pin

1-37

MX-G50

3. Pin function

Pin No. Symbol I/O Description

32 GND P Main ground 33 TZC/

SSTOP

I Tracking zero crossing input & Check the position of pick-up

not 34 TEIO B Tracking error output & Tracking servo input 35 LPFT I Tracking error integration input (to automatic control) 36 ATSC I Anti-shock input 37 LD O APC amp. output 38 PD I APC amp. input 39 PDAC I Photo diode A & C RF I/V amp. inverting input 40 PDBD I Photo diode B & D RF I/V amp. inverting input 41 PDF I Photo diode F & tracking(F) I/V amp. inverting input 42 PDE I Photo diode E & tracking(E) I/V amp. inverting input 43 DCB I Capacitor connection to limit the defect detection 44 MCP I Capacitor connection to mirror hold 45 DCCI O Output pin to connect the component for defect detect

(2/2)

wherther inside or

46 DCCO I Input pin to connect the component for defect detect 47 VREF O (VCC+GND)/2 Voltage reference output 48 EQC I AGC_equalize level control terminal & capacitor terminal to input in to VCA

BA3837 (IC301) : Mic mixer

1.Block diagram

C B A ROUT LP LP LP RIN

16 15 14 13 12 11 10 9

–

SW1

+

R

L + R

L – R

L

+

– +

–

+

LOGIC

–

+

–

123456 78

V

CC

MIC LOUT FK TK LIN BIAS GND

–

SW2

+

–

1-38

L4959 (RIC1) : Voltage regulator

1.Pin layout

MX-G50

TAB CONNECTED TO PIN 6

2.Block diagram

2/10

V

S

EN 8V

EN 12V(a)

EN 12V(b)

8

7

5

REF

GEN

11 10

9 8 7 6 5 4 3 2 1

D97AU716A

OUT 12V(a) V

S

OUT 8.6V EN 8.6V EN 12V(a) GND EN 12V(b) N.C. OUT 5.6V V

S

OUT 12V(b)

5.6V, 250mA

3

OUT 5.6V

REGULATOR

8.6V, 600mA

REGULATOR

9

OUT 8.6V

SWITCHED

12V, 800mA

REGULATOR

11

OUT 12V(a)

SWITCHED

12V, 1.3A

REGULATOR

1

OUT 12V(b)

SWITCHED

D97AU569C

3.Pin function

Pin Pins Description

1 OUT 12V (b) 12V/1.3A SWITCHED OUTPUT VOLTAGE 2V

S

3 OUT 5.6V 5.6V/250mA OUTPUT VOLTAGE 4 N.C. not connected 5 EN 12V (b) Enable 12V/1.3A SWITCHED OUTPUT VOLTAGE 6 GND Ground 7 EN 12V (a) Enable 12V/0.8A SWITCHED OUTPUT VOLTAGE 8 EN 8.6V Enable 8.6V/0.6A SWITCHED OUTPUT VOLTAGE 9 OUT 8.6 8.6V/0.6A SWITCHED OUTPUT VOLTAGE

10 V

S

11 OUT 12V (a) 12V/0.8A SWITCHED OUTPUT VOLTAGE

Supply Voltage

GND

6

1-39

MX-G50

LC72131M(IC02): PLL frequency synthesizer for electron alignment

1. Pin layout

1

XIN

2

CE

3

DI

4

CL

5

DO

6

BO1

7

BO2

8

BO3

9

BO4

10

I01

20 19 18 17 16 15 14 13 12 11

XOUT VSS AOUT AIN PD VDD FMIN AMIN 102 IFIN

2. Block diagram

1

20

14

13

2

3

4 5

15 19

CCB I/F

Power on Reset

Reference Driver

1 2

Swallow Counter 1/16,1/17 4bits

12bits Programmable Divider

Data Shift Register & Latch

Phase Detector Charge Pump

Unlock Detector

Universal Counter

16 17 18

11

3.Pin Functions

Symbol

XIN XOUT

FMIN

AMIN

Pin No.

1 20

14

13

Type

Xtal OSC

Local oscillator signal input

6

7

Functions

Crystal resonator connection (4.5MHz/7.2MHz)

Serial data input : FMIN is selected when DVS is set to 1. The input frequency range is from 10 to 160MHz. The signal is passed through a built-in divide-by-two prescaler and then supplied to the swallow counter. A1 though the range of divisor setting is from 272 to 65, 535, the actual divisor is twice the setting since there is also a built-in divide-by-two prescaler.

Serial data input : AMIN is selected when DVS is set to 0. Serial data input : When SNS is set to 1 : The input frequency range is form 2 to 40MHz The signal is supplied directly to the swallow counter. The range of divisor setting is from 272 to 65, 535 and the actual divisor will be the value set. Serial data input : When SNS is set to 0 : The input frequency ranges is from 0.5 to 10MHz. The signal is supplied directly to a 12-bit programmable divider. The range of divisor setting is from 4 to 4,095 and the actual divisor will be the value set.

9

8

1210

(1/2)

Circuit configuration

1-40

CE

2

Chip enable

Most be set high when serial data is input to the LC72131M (DI ), or when serial data is output (DO).

S

MX-G50

3.Pin Functions

Symbol

CL

DI

DO

VDD

VSS

BO1 BO2

BO3 BO4

Pin No.

15

19

6 7

8 9

4

3

5

Type

Clock

Input data

Output data

Power supply

Ground

Output port

Functions

Used as the synchronization clock when serial data is input to the LC72131 (DI ), or when serial data is output (DO).

Inputs serial data sent from the controller to the LC72131M.

Output serial data sent from the LC72131M to the controller. The content of the output data is determined by the serial data DOCO to DOC2.

The LC72131M power supply (VDD=4.5 to 5/5V) The power on reset circuit operates when power is first applied.

The LC72131M ground.

Dedicated output pins The output states are determined by BO1 to BO4 in the serial data. 'Data"=0:Open =1:Low The pins go to the open state after the power-on reset. An 8Hz time base signal can be output from BO1 when TBC in the serial data is set to 1. Note that the ON impedance of the BO1 pin is higher than that of the other pins (BO2 to BO4)

(2/2)

Circuit configuration

S

IO1

IO2

PD

AIN AOUT

10

12

16

17 18

I/O Port

Charge pump output

L.P.F amplifier Tr

Pins used for both input and output The input or output state is determined by bits IOC1 and IOC2 in the serial state. 'Data"=0:Input port =1:Output port When specified for use as an input port : The input state is transmitted to the controller through the DO pin. 'Input state"=Low:data value 0 =High:data value 1 When specified for use as an output port : The output state is determined by bits IO1 and IO2 in the serial sate. 'Data"=0:Open =1:Low These pins go to the input port state after the power-on reset.

PLL Charge pump output When the frequency generated by dividing the Local oscillator frequency by N is higher than the reference frequency, a high level will be output from the PD in. similarly, when that frequency is lower, a low level will be output. The PD pin goes to the high impedance state when the frequencies agree.

The MOS transistor used for the PLL active Low-pass filter.

S

IFIN

11

IF counter

The input frequency range is from 0.4 to 12MHz. The signal is supplied directly to the IF counter. The result from the IF counter MBS is output through the DO pin. There are four measurement periods: 4, 8, 32 or 64ms.

1-41

MX-G50

M66010 (UIC2) : I/O control

1.Pin layout

D0 D1

CLK

CS

Vcc

GND

D24 D23 D22 D21 D20 D19 D18 D17

GND

2.Block diagram

CLOCK INPUT CLK

SET INPUT S

CHIP SELECT CS

INPUT

SERIAL DATA DI

INPUT

DO

1

DI

2

CLK

3

CS

4 5

S

6 7

D24

8

D23

9

D22

10

D21

11

D20

12

D19

13

D18

14

D17

15 16

3

6

4

2

D1

32

D2

31

D3

30

D4

29

D5

28

D6

27

D7

26

D8

25

D9 D10 D11 D12 D13 D14 D15 D16

Control circuit

24 23 22 21 20 19 18 17

D24 D23 D22 D3 D2 D1

Q24 Q23 Q22 Q3 Q2 Q1

D24 D23 D22 D3 D2 D1

Q24 Q23 Q22 Q3 Q2 Q1

D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 D16

Shift register 1

Parallel output latch

DI

Shift register 2

DO

GND GND

Vcc

5

DO SERIAL DATA

1

OUTPUT

32

D1

31

D2

30

D3

PARALLEL DATA I/O

10

D22

9

D23

8

D24

7

16

STK402-040 (AIC1) : 2channel AF power amp.

1.Pin layout

+

ch.1

_

NF

NC

_

STK402-040

1

15

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

CH1

IN

STK402-090 (AIC2) : 2channel AF power amp.

1.Pin layout

+

ch.1

_

NC

NF

1-42

STK402-090

1

15

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

CH1

IN

Pre

Vcc

Pre

Vcc

BIAS

CH1

VE

CH1

VE

CH1

-VE

CH1

-VE

Vcc -Vcc

CH2

CH2 +VE

+VE

CH2 +VE

CH2

-VE

CH2

-VE

ch.2

Pre

-Vco

ch.2

Pre

-Vco

+

+ _

_

SUB

GND

+ _

SUB

GND

CH2

NF

CH2

NF

CH2

IN

CH2

IN

TDA7442D (FIC1) : Audio processor

1.Pin layout

MX-G50

R_IN3 R_IN2 R_IN1

L_IN1 L_IN2 V L_IN3 L_IN4

MUXOUTL

IN(L)

MUXOUT(R)

IN(R)

BIN(R)

BOUT(R)

BIN(L)

1 2 3 4 5 6 7 8 9 10 11 12 13 14

2.Block diagram

MUXOUT(L)

0.47 F

L-IN1

L-IN2

L-IN3

L-IN4

R-IN1

R-IN2

R-IN3

R-IN4

4

50K

5

50K

6

50K

7

50K

3

50K

2

50K

1

50K

28

50K

31.5dB control

MUXOUT(R)

+

2.2 F

+

2.2 F

28 27 26 25 24

R_IN4 LOUT ROUT AGND

S

CREF23

SYMULATED

-

L-R

+

SDA SCL DIG-GND TREBLE(R) TREBLE(L) PS1 LP BOUT(L)

100nF

PS1

17

RPS1

PS1 90Hz

MUSIC

LPF 9KHz

24 25 2316

LP

1.2nF

OFF

V

S

SYMULATED

EFFECT

CONTROL

MUSIC/

SUPPLY

AGND

CREF

22 F

MIXING

AMP

MIXING

AMP

5.6nF

TREBLE-L

18

OFF

SURR

TREBLE

SURR

OFF

Vref

TREBLE-R

5.6nF

5.6K

100nF

BIN(L)

BOUT(L)

15

14

RB

FIX

BASS

I2C BUS DECODER + LATCHES

BASS

12

BIN(R) BOUT(R)

100nF 100nF

5.6K

FIX

VAR

RB

1319

79dB CONTROL

-

VAR

+

FIX

+

-

SPKR

ATT

MUTE

SPKR

ATT

MUTE

79dB CONTROL

D98AU947A

27

LOUT

21

SCL

22

SDA

20

DIG GND

26

ROUT

22 21 20 19 18 17 16 15

IN(L)

98

30K

L+R

30K

1110

IN(R)

1-43

MX-G50

VICTOR COMPANY OF JAPAN, LIMITED

AUDIO & COMMUNICATION BUSINESS DIVISION PERSONAL & MOBILE NETWORK BUSINESS UNIT. 10-1,1chome,Ohwatari-machi,Maebashi-city,371-8543,Japan

(No.20978)

200107(V)

JVC MX G50 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Wiring connection

Adjustment method

Flow of functional operation until TOC read

Troubleshooting

Description of major ICs