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MX-J770V MX-J880V

SERVICE MANUAL
COMPACT COMPONENT SYSTEM

MX-J770V MX-J880V
SOUND MODE VOCAL MASKING

Area Suffix
US UX Singapore Saudi Arabia

ECHO

SLEEP

COMPACT

FM MODE STILL

V.INTRO HIGHLIGHT SUBTITLE

TAPE A/B

REC START/STOP

ON SCREEN

PREV

NEXT

SUPER VIDEO
COMPACT

KEY CONTROL

SELECT FADE MUTING

RM­SMXJ770V REMOTE CONTROL

DIGITAL VIDEO

This illustration is MX-J770V

COMPACT

DIGITAL AUDIO

Each difference point
Model MX-J770V MX-J880V CD/DECK/RECEIVER CA-MXJ770V CA-MXJ880V SPEAKER SP-MXJ770V SP-MXJ880V Color Tray fitting Silver Panel Silver & blue Champagne-gold Net Light blue Gray Front Silver Champagne-gold

Contents
Safety precautions Important for laser products Preventing static electricity Precautions at disassembly and parts replacement Disassembly method Adjustment method 1-2 1-3 1-4 1-5 1-6 1-31 Diagnosis which uses extension wire method Flow of functional operation until TOC read Maintenance of laser pickup Replacement of laser pickup Description of major ICs 1-35 1-36 1-37 1-37 1-38

COPYRIGHT

2000 VICTOR COMPANY OF JAPAN, LTD.

No.20861 Jul. 2000

MX-J770V/MX-J880V

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 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 current 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 AC VOLTMETER metal part and a known good earth ground. (Having 1000 Measure the AC voltage across the resistor with the ohms/volts, AC voltmeter. or more sensitivity) Move the resistor connection to each exposed metal part, particularly any exposed metal part having a 0.15 F AC TYPE return path to the chassis, and measure the AC Place this voltage across the resistor. Now, reverse the plug in probe on the AC outlet and repeat each measurement. Voltage each exposed 1500 10W measured any must not exceed 0.75 V AC (r.m.s.). metal part. This corresponds to 0.5 mA AC (r.m.s.).
Good earth ground

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. ! 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. 1-2

MX-J770V/MX-J880V

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 an adjustment 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 näkymättömälle lasersäteilylle.Älä katso säteeseen.

ADVARSEL : Usynlig laserstråling ved åbning , når sikkerhedsafbrydere er ude af funktion. Undgå udsættelse for stråling. ADVARSEL : Usynlig laserstråling ved åpning,når sikkerhetsbryteren er avslott. unngå utsettelse for stråling.

REPRODUCTION AND POSITION OF 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 ADVARSEL :Usynlig laserstråling denna del är öppnad och spårren är urkopplad. Betrakta ej strålen. (s) ved åbning , når sikkerhedsafbrydere er ude af funktion. Undgå udsættelse for stråling. (f)

CLASS 1 LASER PRODUCT

1-3

MX-J770V/MX-J880V

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. 1-4

CD changer mechanism assembly

CD traverse unit

Fig.1

Flexible cable

Soldering Fig.2

MX-J770V/MX-J880V

Precautions at disassembling and parts replacement
This model is charged with electricity on the power board even if the power cord is unplugged. Therefore, always discharge electricity in accordance with the steps given below before starting disassembling of the unit and/or replacement of parts. 1. While referring to the disassembling steps, remove the metal cover and the CD changer mechanism. 2. Set electrical resistances of 1kohm, 1/4W to the places between the + and - terminals of condensers VH(C204, C205) and VL(C214, C215) on the power board, and discharge electricity for 4 ~ 5 seconds. Connection should be made at first for VH. C214 C205 C204 C215

Power board

1-5

MX-J770V/MX-J880V

Disassembly method
Removing the metal cover (See Fig.1 to 3)
1. Remove the six screws A attaching the metal cover on the back of the body. 2. Remove the two 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

Metal cover

A

A

Fig.1
Metal cover

B

Fig.2
Metal cover

Fig.3

B

1-6

MX-J770V/MX-J880V Removing the CD changer mechanism assembly (See Fig.4 to 6)
Prior to performing the following procedure, remove the metal cover.
CD changer mechanism assembly Front panel assembly CD changer mechanism board

C
1. For the card wire connecting the CD changer mechanism board and the main board, disconnect it from connector CN868 on the main board. 2. Remove the two screws C attaching the CD changer mechanism assembly on both sides of the body. 3. Remove the two screws D attaching the CD changer mechanism assembly to the rear panel. Remove the screw E attaching the AUX terminal, two screws F attaching main speakers terminal and two screws H attaching the sub woofers terminal on the back of the body. 4. Remove the screw G attaching the CD optical digital output terminal and screw I attaching video out terminal.
CN102 Main board CN868 CN871 Rear panel CN870

Fig.4
CD changer mechanism assembly Rear panel

Input / output board

Front panel assembly

5. Disconnect the harness from connector CN102 on the video CD board, and pull out the earth wire TW100 on the video CD board. 6. Pull the top of rear panel and the front panel assembly outward respectively, then remove the CD changer mechanism assembly and video out terminal by lifting the rear part of the CD changer mechanism assembly.

C
TW100

Fig.5

D I G E F
SUB WOOFERS terminal

Rear panel

Removing the video CD board (See Fig.7)
Prior to performing the following procedure, remove the CD changer mechanism assembly. 1. Reverse the CD changer mechanism assembly. 2. Remove the two screws J attaching the bracket. 3. Remove the screw K attaching the video CD board. 4. Disconnect the card wire from connector CN100 and CN101 on the video CD board. 5. At first, remove the claw a. Then remove the claw b while raising the video CD board in the direction of the arrow mark as figure. After removing the claw b, you can removing the video CD board by pulling it backward.

H
Bracket Video CD board CN100

Fig.6

J

MAIN SPEAKERS terminal

Video out board CLAW a CLAW b CN101

K
Video CD board CD changer mechanism assembly

Fig.7 1-7

MX-J770V/MX-J880V Removing the front panel assembly (See Fig.8 to 10)
Prior to performing the following procedure, remove the metal cover and the CD changer mechanism assembly. 1. Remove the four screws L attaching the front panel assembly on the bottom of the body. 2. Disconnect the card wire from connector CN865 on the main board and pull out the earth wire on the main board. 3. Disconnect the card wire from connector CN315 on the input / output board. Fig.8 4. Disconnect the harness from connector CN901 on the relay board on the back of the front panel assembly. 5. Disconnect the harness from connector CN912 on the input / output board. 6. Disconnect connector CN870 and CN871 on the input/output board from the main board.
Earth wire Main board CN865 Front panel assembly

L
Front panel assembly

7. Release the two joints c and d on the lower part of the sides using a screwdriver, and remove the front panel assembly toward the front.
Joint c Relay board CN901

Fig.9
Front panel assembly CN871 CN870

Main board CN865 CN912 CN315

Joint d

Input / output board

Fig.10

1-8

MX-J770V/MX-J880V Removing the Microphone terminal board assembly (See Fig.11 and 12)
Prior to performing the following procedure, remove the metal cover, CD changer mechanism assembly and the front panel assembly. MIC volume knob 1. Pull out the MIC volume knob from the front side. 2. Remove the two screws M attaching the microphone terminal board assembly. Fig.11 3. Remove the screw N attaching earth wire. Then release the earth wire from the clamp on the upper part of the cassette mechanism assembly. 4. Remove the microphone terminal board assembly toward you.

Microphone terminal board assembly

M M N
Fig.12

Removing the rolling panel assembly (See Fig.13 and 14)
Prior to performing the following procedure, remove the microphone terminal board assembly. 1. Disconnect the harness from connector CN900 and the card wire from connector CN906 on the relay board on the back of the rolling panel assembly respectively. 2. Disconnect the harness from connector CN862, CN863, CN850, CN851 and CN815 on the main board respectively. Disconnect the card wire from connector CN880 on the main board. 3. Disconnect the card wire from connector CN869 and the harness from CN883 and CN884 on the main board respectively. 4. Remove the four screws O attaching the rolling panel assembly. ATTENTION: For the harness which should be connected to connector CN869, CN883 and CN884 on the main board, get them through the slots under the rolling panel when reattaching the rolling panel assembly to the front panel (Refer to Fig.14)

Main board

O
Relay board CN900

O O

O

Relay board CN906 Rolling panel assembly

Cassette mechanism assembly

Fig.13
CN883,CN884 CN869 CN815 Main board CN850,CN851 Main board CN862,CN863 Rolling panel assembly

Main board CN880 Relay board CN900

Fig.14 1-9

MX-J770V/MX-J880V Removing the main board (See Fig.15 and 16)
Prior to performing the following procedure, remove the front panel assembly, the microphone terminal board and the rolling panel assembly. 1. Disconnect the harness from connector CN867 on the main board. 2. Disconnect the card wire from connector CN879 on the main board (Before pulling out the card wire, stand the part e of CN879 as shown in Fig.16). 3. Remove the two screws P attaching the main board.
Rolling panel assembly

P

CN867 CN879

Main board

P

Fig.15
e

CN879

Removing the cassette assembly (See Fig.17)

mechanism

Fig.16

Prior to performing the following procedure, remove the front panel assembly. 1. Disconnect the card wire from connector CN306 on the cassette mechanism board. 2. Remove the four screws Q and three screws R attaching the cassette mechanism assembly.

Q

Q

R

CN306

R
Fig.17

R

Cassette mechanism board

1-10

MX-J770V/MX-J880V Removing the boards in the front panel assembly (See Fig.18 to 20)
Prior to performing the following procedure, remove the front panel assembly and the rolling panel assembly. Function board1 (See Fig.18) 1. Remove the two screws S attaching the function board 1.
Function board 2

T T

S S
Function board 1

Function board2 (See Fig.18) 1. Remove the two screws T attaching the function board 2. Bass-level regulator board (See Fig.19) 1. Pull out the sub woofer volume knob on the front side of the front panel assembly and remove the nut attaching the bass-level regulator board. 2. Release the two joints f. Unsolder FW951 on the bass-level regulator board and disconnect the harness connected to the power switch. Eject switch board

Fig.18

Power switch board FW951 Bass-level regulator board

FW850 Joints g

U
Joints f

Main volume & headphone board (See Fig.19) 1. Pull out the volume knob on the front side of the front panel assembly and remove the nut attaching the main volume & headphone board. 2. Remove the two screws U attaching the main volume & headphone board on the back of the front panel assembly and release the two joints g. 3. Unsolder FW850 on the main volume & headphone board and disconnect the harness connected to the eject switch board. 4. Remove the screw V attaching the earth wire extending from the main volume & headphone board.

V
Cassette mechanism assembly Main volume & headphone board

Fig.19

1-11

MX-J770V/MX-J880V
Power switch board (See Fig.20) 1. Remove the two screws W attaching the power switch board. Unsolder FW951 on the power switch board and disconnect the harness extending to the bass-level regulator board. Eject switch board (See Fig.20) 1. Remove the four screws X attaching the eject switch board. Unsolder FW850 on the eject switch board and disconnect the harness extending to the main volume & headphone board. Remote control port board (See Fig.20) 1. Remove the screw Y attaching the remote control port board.
Main volume & headphone board Bass-level regulator board Eject switch board FW850 FW951 Remote control port board

X

Y W

Power switch board

X

Fig.20

Removing the relay board and fixing board (See Fig.21)
Prior to performing the following procedure, remove the metal cover and CD changer mechanism assembly. There is no need to remove the front panel assembly. 1. Disconnect the harness from connector CN900 and CN901 on the relay board on the back of the rolling panel assembly. 2. Disconnect the card wire from connector CN905 and CN906 on the relay board on the back of the rolling panel assembly. 3. Remove the screw Z attaching the relay board. Remove the relay board from the groove i.
Relay board

CN905

Rolling panel assembly

Z

CN900 CN901 Groove i

A
Fixing board Groove j

4. Remove the screw A attaching the fixing board and remove the fixing board from the groove j.

CN906

Fig.21

1-12

MX-J770V/MX-J880V Removing the tuner board (See Fig.22 and 23)
Prior to performing the following procedure, remove the metal cover and CD changer mechanism assembly. 1. Remove the two plastic rivets attaching the joint board, and remove the joint board. 2. Disconnect the card wire from connector CN1 on the tuner board. 3. Remove the two screws B attaching the tuner board on the back of the body.
CN712 C CN711 Input / output board Joint board Plastic rivet Tuner board CN1 Rear panel CN871

CN870

CN315

Fig.22

Removing the input / output board (See Fig.22 and 23)
Prior to performing the following procedure, remove the tuner board. 1. Disconnect the card wire from connector CN315 on the input / output board. 2. Remove the screw C attaching the input / output board on the lower side of the body. 3. Remove the five screws, E, F & H attaching the AUX, main speakers, sub woofers terminal board on the back of the body. 4. Remove the screw G attaching the CD optical digital output back of the body. 5. Disconnect the harness from connector CN912 on the input / output board and pull out the earth wire on the main board. 6. Disconnect connector CN870, CN871, CN612, CN711 and CN712 on the input / output board by pulling out them outward. Remove the input / output board from the body.

Rear panel

B

G E F H
Fig.23

1-13

MX-J770V/MX-J880V Removing the rear cover / rear panel (See Fig.24 to 27)
Prior to performing the following procedure, remove the metal cover and the CD changer mechanism assembly. There is no need to remove the front panel assembly. 1. Remove the two screws D attaching the rear cover on the back of the body. 2. Remove the five screws E & F, H attaching AUX, main speakers and sub woofers terminal board to the rear panel on the back of the body. 3. Remove the screw G attaching the CD optical digital output terminal. 4. Remove the five screws Z attaching the heat sink and the pre-amplifier board to the rear panel on the back of the body. 5. Remove the two screws Y attaching the voltage selector to the rear panel on the back of the body. 6. Remove the screw X attaching the rear panel to the chassis base on the back of the body. 7. Remove the two screws B attaching the tuner board on the back of the body. 8. Release the two joints k and l on the rear panel bottom using a screwdriver, and detach the rear panel backward.
Rear cover Rear panel

D

Fig.24

B
Heat sink

G E Z F H Z X
Fig.25

Z Y

Z

Rear panel

Rear panel

Joint l

Joint k

Fig.27

Fig.26

1-14

MX-J770V/MX-J880V Removing the pre-amplifier board / heat sink (See Fig.28 to 30)
Prior to performing the following procedure, remove the metal cover, the CD changer mechanism assembly, the tuner board, input / output board and the rear cover / rear panel. There is no need to remove the front panel assembly. 1. Disconnect the harness from connector CN901 on the relay board on the back of the rolling panel assembly. 2. Disconnect the harness from connector CN713 on the pre-amplifier board. 3. Remove the two screws H attaching the heat sink to the power & main amplifier board on the back of the body. 4. Remove the fore screws I & J attaching the preamplifier board and IC to the heat sink. 5. Remove the bracket, then detach the pre-amplifier board from the heat sink. Fig.28
Pre-amplifier board CN713 Relay board CN901

Pre-amplifier board

Power & main amplifier board

H

Heat sink

Fig.29

J I
Pre-amplifier board

IC

Bracket Heat sink

Fig.30

1-15

MX-J770V/MX-J880V Removing the power & main amplifier board (See Fig.31 and 32)
Prior to performing the following procedure, remove the metal cover, the CD changer mechanism assembly, the rear cover / rear panel, the tuner board, the input / output board and the pre-amplifier board. 1. Remove the four screws K attaching the transf. on the power & main amplifier board through the upper side slots. Power & main
amplifier board

Plastic rivet

K

Plastic rivet

K

2. Remove the two plastic rivets fixing the power & main amplifier board. 3. Remove the cord stopper by pushing it upward. 4. Cut off the bands m and n fixing the power cord and unsolder the power cord on the power & main amplifier board. Fig.31

K

Power & main amplifier board

Soldered part

Cord stopper

Band m Fig.32

Band n

1-16

MX-J770V/MX-J880V Removing the multi-control assembly (See Fig.33 to 35)
Prior to performing the following procedure, remove the rolling panel assembly and the main board. 1. Remove the two screws L attaching the multi-control assembly on both sides. 2. Remove the multi-control assembly outward while pushing the right and left hooks fixing multi-control assembly outward respectively.
Multi-control assembly

Fig.33

L

Multi-control assembly

L
Removing the multi-control board (See Fig.36 to 38)
Prior to performing the following procedure, remove the rolling panel assembly, the main board and the multi-control assembly.

Fig.34

Hook

1. Remove the four screws M attaching the cover and the bracket. 2. Pull out the right and left panel holders outward respectively by releasing the tabs o outward. 3. Remove the cover and the bracket. 4. Remove the two screws N attaching the multi-control board.

Multi-control assembly

Fig.35

M
Bracket

M
Bracket

Cover Fig.36

N
Tab o Bracket

Multi-control board

Panel holder

Fig.38

Fig.37

1-17

MX-J770V/MX-J880V Removing the drive motor assembly (See Fig.39 to 42)
Prior to performing the following procedure, remove the rolling panel assembly and the main board. 1. Remove the relay board and fixing board (Refer to Fig.21). 2. Remove the two screws O attaching the motor bracket and remove the motor lead staple p. 3. Remove the two screws P attaching the shaft bracket. 4. Remove the motor belt. 5. Remove the three screws Q attaching the side bracket. 6. Remove the shaft assembly from the rolling panel assembly by lift up the shaft assembly upward. 7. Remove the drive motor upward.
Relay board CN906 CN905 Rolling panel assembly

Z
CN900 CN901 Groove i Groove j

A
Fixing board

Fig.21

Z
Relay board

A
Fixing board

Fig.39

P

O
Motor bracket

Motor belt

Shaft bracket Motor lead staple p

Fig.40

Side bracket

Q
Shaft assembly

Drive motor Fig.41

Fig.42 1-18

MX-J770V/MX-J880V Removing the super VCD control board (See Fig.43)
Prior to performing the following procedure, remove the metal cover and the CD changer mechanism assembly. 1. Disconnect the card wire from connector CN101 and CN102 on the super VCD control board. 2. Remove the two plastic rivets attaching the super VCD control board.
CN101 CD changer mechanism assembly CN102

Plastic rivet

Plastic rivet

Super VCD control board

Fig.43

1-19

MX-J770V/MX-J880V < Speaker section > Removing the speaker cover (See Fig.1)
1. Remove the five screws A attaching the speaker cover on the side of the body.
Screw A Screw A

Removing the sub woofer unit (See Fig.2 and 3)
1. Remove the four screws B attaching the sub woofer unit. 2. Two plug wires connected with the sub woofer unit are pulled out.

Speaker cover Fig.1 Sub woofer unit Screw B

Removing the ornament panel assembly (See Fig.4 to 8)
1. Remove the saran board from the speaker box. (Saran board can be detached by pulling the side of Saran board forward.) 2. The plus driver is inserted in the holder, it is lifted, and the holder is removed. 3. Four holders are removed, and four screws C under that are removed. 4. The minus driver is inserted in the concave part in the speaker box bottom and inserts in the interior little by little. CAUTION : Please apply the felt or the cloth, etc. to damage neither the ornament panel nor the cabinet when the ornament panel assembly is detached when working. 5. Two plug wires connected with the middle range unit are pulled out.
Holder Sub woofer unit Screw B

Fig.2

Plug wire Plug wire (Black) (Red) Fig.3 Ornament panel assembly

Ornament panel assembly Fig.6 top Middle range unit Plug wire (Yellow)

Saran board Fig.4

Bottom concave part Fig.7

Ornament panel assembly Plug wire (Black)

Holder & screw C

Holder & screw C Fig.5

Fig.8

1-20

MX-J770V/MX-J880V Removing the middle range unit (See Fig.9)
1. Remove the ornament panel assembly. 2. Remove the two screws D attaching the middle range unit. 3. Two plug wires connected with the middle range unit are pulled out.
Screw D Middle range unit Plug wire (White) Plug wire (Blue) Screw D Ornament panel assembly

Removing the woofer unit (See Fig.10 and 11)
1. Remove the ornament panel assembly. 2. Remove the four screws E attaching the woofer unit. 3. Two plug wires connected with the woofer unit are pulled out.
Woofer unit Fig.9

Plug wire (Blue / Black) Fig.10 Screw E

Plug wire (Yellow / Black)

Woofer unit

Screw E Fig.11

1-21

MX-J770V/MX-J880V A Removing the CD Servo control board (See Fig.1)

1.Remove the metal cover. 2.Remove the CD changer mechanism assembly. 3.From bottom side the CD changer mechanism assembly, remove the two screws A retaining the CD servo control board. 4.Absorb the four soldered positions "a" of the right and left motors with a soldering absorber. 5.Pull out the earth wire on the CD changer mechanism assembly. 6.The two screws B is removed and C.B.holder is detached. 7.Disconnect the connector CN854 on the CD servo control board. 8.Disconnect the card wire CN601 and the connector CN801 on the CD servo control board.

a a
CN854

A
CN651

CD servo control board
CN652 CN801 CN151

CN601

Removing the CD tray assembly (See Fig.2~4) 1. Remove the front panel assembly.
2. Remove the CD changer mechanism assembly. 3. Remove the CD Servo control board. 4. Remove the screw C' retaining the lod stopper. 5. From the T.bracket section "b" and clamper base section "c" , remove both of the edges fixing the rod(See Fig.2 and 3). 6. Remove the screw D retaining the disc stopper (See Fig.3). 7. Remove the three screws E retaining the T.bracket (See Fig.3). 8. Remove the screw F retaining the clamper assembly (See Fig.3). 9. From the left side face of the chassis assembly, remove the one screw G retaining both of the return spring and lock lever(See Fig. 4). 10. By removing the pawl at the section "d" fixing the return spring, dismount the return spring(See Fig.4). 11. Remove the three lock levers(See Fig.4). T.Braket Disc stopper

Earth wire

B

B
Fig.1

C.B.Holder

Clamper base

b
Rod T.Braket

c
Fig.2

d D E a C
Lod stopper (C/J version only)

E

E F b
Lock lever Clamper ass'y

Return spring

G

Fig.4 Fig.3

1-22

MX-J770V/MX-J880V
11. Check whether the lifter unit stopper has been caught into the hole at the section "e" of CD tray assembly as shown in Fig.5. 12. Make sure that the driver unit elevator is positioned as shown in Fig.6 from to the second or fifth hole on the left side face of the CD changer mechanism assembly. [Caution] In case the driver unit elevator is not at above position, set the elevator to the position as shown in Fig.7 by manually turning the pulley gear as shown in Fig.8. 13. Manually turn the motor pulley in the clockwise direction until the lifter unit stopper is lowered from the section "e" of CD tray assembly(See Fig.8). 14. Pull out all of the three stages of CD tray assembly in the arrow direction "f" until these stages stop (See Fig.6). 15. At the position where the CD tray assembly has stopped, pull out the CD tray assembly while pressing the two pawls "g and g' " on the back side of CD tray assembly(See Fig.9). In this case, it is easy to pull out the assembly when it is pulled out first from the stage CD tray assembly. Stopper

e
CD tray assembly

Fig.5
Chassis assembly

f

CD tray assembly Drive unit of elevator

Refer to Fig.7

Pawl

g

Fig.7

Fig.6

CD tray assembly

Pulley gear

Motor pulley Pawl

Fig.8

g , g'

Fig.9

1-23

MX-J770V/MX-J880V Removing the CD loading mechanism assembly(See Fig.10)
1. While turning the cams R1 and R2 assembly in the arrow direction "h" ,align the shaft "i" of the CD loading mechanism assembly to the position shown in Fig.10. 2. Remove the four screws H retaining the CD loading mechanism assembly. Cams R1, R2 assembly

Arrow

h i H

Removing the CD traverse mechanism (See Fig.11 and 12 )
1. For dismounting only the CD traverse mechanism without removing the CD loading mechanism assembly, align the shaft "j" of the CD loading mechanism assembly to the position shown Fig.11 while turning the cam R1 and R2 assembly in the arrow direction "k" . 2. By raising the CD loading mechanism assembly in the arrow direction "l", remove the assembly from the lifter unit

H

Cam R1, R2 assembly

H
CD loading mechanism assembly

H
Fig.10
CD traverse mechanism

Arrow

k

j
Lifter unit Arrow

k

Fig.11 Fig.12
CD Pickup unit

Removing the CD pick unit (See Fig.13 )
1. Move the cam gear in the arrow direction "m" . Then, the CD pickup unit will be moved in the arrow direction "n" . 2. According to the above step, shift the CD pickup unit to the center position. 3. While pressing the stopper retaining the shaft in the arrow direction "o" , pull out the shaft in the arrow direction "p". 4. After dismounting the shaft from the CD pickup unit, remove the CD pickup unit

n m

CD loading mechanism Shaft Cam gear

Shaft

Shaft

o
Stopper

p
Stopper

Fig.13 1-24

MX-J770V/MX-J880V Removing the cam unit (See Fig.14 ~17 )
1. Remove the CD loading mechanism assembly. 2. While turning the cam gear "q", align the pawl "r" position of the drive unit to the notch position(Fig.16) on the cam gear "q". 3. Pull out the drive unit and cylinder gear(See Fig.17). 4. While turning the cam gear "q", align the pawl "s" position of the select lever to the notch position(Fig.18) on the cam gear "q". 5. Remove the four screws J retaining the cam unit(cam gear "q" and cams R1/R2 assembly)(See Fig.18).

Drive unit Chassis assembly

Cam gear q

Tray select switch board

r

CN802 CN801 CN804

Fig.14

I
Fig.15

Drive unit

J
Cylinder gear Cam gear q

Cams R1, R2 assembly Cam unit

J J s

Fig.16

Select lever

Fig.17

1-25

MX-J770V/MX-J880V Removing the actuator motor and belt (See Fig.18~21)
1. Remove the two screws K retaining the gear bracket (See Fig.19). 2. While pressing the pawl "t" fixing the gear bracket in the arrow direction, remove the gear bracket (See Fig.19). 3. From the notch "u section" on the chassis assembly fixing the edge of gear bracket, remove and take out the gear bracket(See Fig. 20). 4. Remove the belts respectively from the right and left actuator motor pulleys and pulley gears(See Fig. 19). 5. After turning over the chassis assembly, remove the actuator motor while spreading the four pawls "v" fixing the right and left actuator motors in the arrow direction(See Fig. 21). [Note] When the chassis assembly is turned over under the conditions wherein the gear bracket and belt have been removed, then the pulley gear as well as the gear, etc. constituting the gear unit can possibly be separated to pieces. In such a case, assemble these parts by referring to the assembly and configuration diagram in Fig. 22. Chassis assembly Pulley gear Belt Motor pulley Gear bracket

Pulley gear Belt Motor pulley

K

Pawl

t

K
Fig.18
Actuator motor

u v
Gear bracket

v

Fig.19

Fig.20

Assembly and Configuration Diagram
Pulley gear Gear B Pulley gear Cylinder gear

Gear B Gear C Select gear Gross gear L Gross gear U Gear C

Fig.21

1-26

MX-J770V/MX-J880V Removing the cams R1/R2 assembly and cam gear q(See Fig.22)
Slit washer 1. Remove the slit washer fixing the cams R1 and R2 assembly. 2. By removing the two pawls "w" fixing the cam R1, separate R2 from R1. 3. Remove the slit washer fixing the cam gear "q". 4. Pull out the cam gear "q" from the C.G. base assembly. Cam gear L Slit washer Cam R2

L
Pawl Cam R1

w

Pawl

w

Removing the C.G. base assembly (See Fig.22 and 23)
Remove the three screws L retaining the C.G. base assembly. [Caution] To reassemble the cylinder gear, etc.with the cam unit (cam gear and cans R1/R2 assembly), gear unit and drive unit, align the position of the pawl "x" on the drive unit to that of the notch on the cam gear "q". Then, make sure that the gear unit is engaged by turning the cam gear "q" (See Fig. 24).

Cam switch board C.G. base assembly

Fig.22
Cam gear L Cam R1, R2 assembly

Notch

Pawl

x

Gear unit

Cylinder gear

Drive unit

Gear bracket

Fig.23

1-27

MX-J770V/MX-J880V

< Cassette mechanism section >
Removing the playback,recording and eraser heads (See Fig.1~3)
1. While shifting the trigger arms seen on the right side of the head mount in the arrow direction,turn the flywheel R in counterclockwise direction until the head mount has gone out with a click (See Fig. 1). 2. When the flywheel R is rotated in counterclockwise direction, the playback head will be turned in counterclockwise direction from the position in Fig.2 to that in Fig.3. 3. At this position, disconnect the flexible P.C.board (outgoing from the playback head) from the connector CN301 on the head amp. and mechanism control P.C. board. 4. After dismounting the FPC holder,remove the flexible P.C.board. 5. Remove the flexible P.C.board from the chassis base. 6. Remove the spring "a" from behind the playback head. 7. Loosen the reversing azimuth screw retaining the playback head. 8. Take out the playback head from the front of the head mount. 9. The recording and eraser heads should also be removed similarly according to Steps 1~8 above.

Cassette mechanism

Flywheel R

Head mount

Trigger arm (Mechanism A side)

Fig.1

Playback/Recording & eraser head Flexible P.C.board

Spring "a" Trigger arm

CN301 Head amplifier & mechanism control P.C. board Flywheel R

Reassembling the playback, recording and eraser heads (See Fig.2,3)
1. Reassemble the playback head from the front of the head mount to the position as shown in Fig.3. 2. Fix the reversing azimuth screw. 3. Set the spring a from behind the playback head. 4. Attach the flexible P.C.board to the chassis base, and fix it with the FPC holder as shown in Fig.3. 5. The recording and eraser heads should also be reassembled similarly according to Steps 1~4 above.

Fig.2

(Mechanism A side)

Playback head

Reversing azimuth screw Head mount Flexible P.C.board CN302

Spring "a"

FPC holder

Fig.3

Head amplifier & mechanism control P.C. board (Mechanism B side)

1-28

MX-J770V/MX-J880V Removing the head amp.and mechanism control P.C.board (See Fig. 4)
1.Remove the cassette mechanism assembly. 2.After turning over the cassette mechanism assembly,remove the five screws "A" retaining the head amp. and mechanism control P.C. board 3.Disconnect the connectors CN303 and CN304 on the P.C.Board and the connectors CN1 on both the right and left side reel pulse P.C.Boards. 4.When necessary, remove the 4pin parallel wire soldered to the main motor

A
CN304

A

Head amplifier & mechanism control board

A

CN303

CN302

CN301

Flexible board

A
Fig.4

Flexible board

A

Removing the capstan motor assembly
1.Remove the six screws "B" retaining capstan motor assembly (See Fig. 5). 2.While raising the capstan motor, remove the capstan belts A and B respectively from the motor pulley (See Fig. 6). Caution 1: Be sure to handle the capstan belts so carefully that these belts will not be stained by grease and other foreign matter. Moreover, these belts should be hand while referring to the capstan belt hanging method.

B

B

Capstan motor assembly

B

B B B
Fig.5

Capstan motor Capstan belt A Capstan belt B

Capstan belt A

Capstan belt B

Motor pulley

Fig.7

Fig.6

1-29

MX-J770V/MX-J880V Removing the capstan motor (See Fig. 8)
From the joint bracket, remove the two screws "C" retaining the capstan motor.
Joint bracket

C

Capstan motor

Removing the flywheel (See Fig. 9,10)
1.Remove the head amp. and mechanism control P.C.Board. 2.Remove the capstan motor assembly. 3.After turning over the cassette mechanism, remove the slit washers "a" and "b" fixing the capstan shafts R and L, and pull out the flywheels R and L respectively from behind the cassette mechanism.

C
Fig.8

Flywheel R

Flywheel L

a
Flywheel R Flywheel L Slit washer "a"

b
Slit washer "b"

Fig.10 Removing the reel pulse P.C.board and solenoid (See Fig. 11)
1.Remove the five pawls (c,d,e,f,g) retaining the reel pulse P.C.Board. 2.From the surface of the reel pulse P.C.Board parts, remove the two pawls "h" and "i" retaining the solenoid.

Fig.9

c

d

e

f

g

Reel pulse board

h
Solenoid

i

Solenoid

Fig.11

1-30

MX-J770V/MX-J880V

Adjustment method
Measurement instruments required for a djustment
1. Low frequency oscillator, This oscillator should have a capacity to output 0dBs to 600ohm at an oscillation frequency of 50Hz-20kHz. 2. Attenuator impedance : 600ohm 3. Electronic voltmeter 4. Frequency counter 5. Wow flutter meter 6. Test tape VTT712 : For Tape speed and wow flutter ( 3kHz) VTT724 : For Reference level (1kHz) TMT7036 : For Head angle(10kHz),Play back frequency characteristics(1kHz),and dubbing frequency characteristics(63,1,10kHz) Because of frequency-mixed tape with 63,1k,10k and 14kHz(250nWb/m -24dB). Use this tape together with a filter. 7. Blank tape TAPE : AC-225, TAPE : AC-514 8. Torque gauge : For play and back tension Forward ; TW2111A, Reverse ; TW2121A Fast Forward and Rewind ; TW2231A 9. Test disc : CTS-1000(12cm),GRG-1211(8cm) 10. Jitter meter Radio input signal AM modulation frequency : 400Hz Modulation factor : 30% FM modulation frequency : 400Hz Frequency displacement : 22.5kHz Frequency Range AM 531kHz~1602kHz FM 87.5MHz~108MHz

Standard measurement positions of volume and switch Power : Standby (Light STANDBY Indicator) S,A,BASS : OFF Sound mode : OFF Main VOL. : 0 Minimum Travers mecha set position : Disc 1 Mic MIX vol : MAX ECHO : OFF Precautions for measurement 1. Apply 30pF and 33kohm to the IF sweeper output side and 0.082 F and 100kohm in series to the sweeper input side. 2. The IF sweeper output level should be made as low as possible within the adjustable range. 3. Since the IF sweeper is a fixed device, there is no need to adjust this sweeper. 4. Since a ceramic oscillator is used, there is no need to perform any MPX adjustment. 5. Since a fixed coil is used, there is no need to adjust the FM tracking. 6. The input and output earth systems are separated. In case of simultaneously measuring the voltage in both of the input and output systems with an electronic voltmeter for two channels, therefore, the earth should be connected particularly. 7. In the case of BTL connection amplifier, the minus terminal of speaker is not for earthing. Therefore, be sure not to connect any other earth terminal to this terminal. This system is of an OTL system.

Measurement conditions
Power supply voltage AC110/127/220-240V(50/60Hz) Measurement output terminal : Speaker out :TP101(Mesuring for TUNER/DECK/CD) :Dummy load 6ohm

1-31

MX-J770V/MX-J880V Arrangement of adjusting positions

Cassette mechanism section (Mechanism A section)

Cassette mechanism section (Back side)

Head azimuth adjusting screw (Forward side)

Head azimuth adjusting screw (Reverse side)

Head azimuth adjusting screw (Forward side)

Playback head

Head azimuth adjusting screw (Reverse side)

Playback,recording and eraser heads or playback head

Cassette Mechanism Unit Section

Tape speed ADJ

Bias ADJ L

Bias ADJ R

1-32

MX-J770V/MX-J880V Tape recorder section
Items Confirmation of head angle Measurement conditions Test tape :TMT7036(10kHz) Measurement output terminal :Speaker terminal Speaker R (Load resistor:3 ) :Headphone terminal Measurement method 1.Playback the test tape TMT7036(10kHz). 2.With the playback mechanism or recording & playback mechanism, adjust the head azimuth screw so that the forward and reverse output levels become maximum.After adjustment,lock the head azimuth at least by half a turn. 3.In either case,this adjustment should be performed in both the forward and reverse directions with the head azimuth screw. Adjust VR301 so that the frequency counter reading becomes 3,000Hz 60Hz when playing back the test tape VTT712(3kHz)with the playback mechanism or playback and recording mechanism after ending forward winding of the tape. Standard values Maximum output Adjusting positions Adjust the head azimuth screw only when the head has been changed.

Confirmation of tape speed

Test tape :VTT712(3kHz) or TMT7036(3kHz) Measurement output terminal :Headphone terminal

Tape speed of decks (A and B) :3,000Hz 60Hz

VR301

Reference values for confirmation items
Items Double tape speed Measurement conditions Test tape :TMT7036(10kHz) Measurement output terminal :Speaker terminal Speaker R (Load resistance:3 ) measurement output terminal :Headphone terminal Measurement method After setting to the double speed motor, confirm that the frequency counter reading becomes 4,800+400/-300Hz when the test tape VTT712 (3kHz) has been play back with the playback mechanism. Adjusting Standard positions values 4,800+400/ Playback -300Hz mechanism side

Difference between the forward and reverse speed. P.mecha and R/P mecha speed Wow & flutter Test tape :TMT7036(10kHz) Measurement output terminal :Headphone terminal

When the test tape VTT712(3kHz) has been played back with the playback mechanism or recording and playback mechanism at the beginning of forward winding, the frequency counter reading of the difference between both of the mechanisms should be 6.0Hz or less.

60Hz or less

Both the playback and recording & playback mechanism

When the test tape VTT712(3kHz) has been played back with the playback mechanism or recording and playback mechanism at the beginning of forward winding the frequency counter reading of wow & flutter should be 0.25% or less(WRMS).

with in 0.25% JIS(WTD)

Both the playback and recording & playback mechanism

1-33

MX-J770V/MX-J880V Electrical performance
Measurement Measurement method conditions Adjustment of *Mode : Forward or 1.With the recording and playback mechanism, recording bias reverse mode load the test tapes(AC-514 to TYP and AC-225 to current *Recording mode TYP ),and set the mechanism to the recording and (Reference *Test tape pausing conditions in advance. value) :AC-514 and AC-225 2.After connecting 100 in series to the recorder Measurement output head,measure the bias current with a valve terminal voltmeter at both of the terminals. :Both recording and 3.After resetting the [PAUSE] mode,start recording. headphone terminals At this time,adjust VR101 for LcH and VR201 for RcH so that the recording bias current values become 4.0 A (TYP ) and 4.20 A(TYP ). Adjustment of recording and playback frequency characteristics Reference frequency :1kHz and 10kHz (REF:-20dB) Test tape :TYP AC-514 Measurement input terminal :OSC IN 1.With the recording and playback mechanism,load the test tape(AC-514 to TYP ),and set the mechanism to the recording and pausing condition in advance. 2.While repetitively inputting the reference frequency signal of 1kHz and 10kHz from OSC IN, record and playback the test tape. 3.While recording and playing back the test tape in TYP ,adjust VR101 for LcH and VR201 for RcH so that the output deviation between 1kHz and 10kHz becomes -1dB 2dB. Items Standard values AC-225 :4.20 A AC-514 :4.0 A Adjusting positions LcH :VR101 RcH :VR201

Output deviation between 1kHz and 10kH :-1dB 2dB

LcH :VR101 RcH :VR201

Reference values for electrical function confirmation items
Measurement conditions Recording *Recording and bias frequency playback side forward or reverse *Test tape :TYP AC-514 *Measurement terminal BIAS TP on P.C.board Eraser current *Recording and (Reference playback side forward value) or reverse *Recording mode *Test tape :AC-514 and AC-225 Measurement terminal Both of the eraser head Items Measurement method 1.While changing over to and from BIAS 1 and 2, confirm that the frequency is changed. 2.With the recording and playback mechanism. load the test tape (AC-514 to TYP ),and set the mechanism to the recording and pausing conditions in advance. 3.Confirm that the BIAS TP frequency on the P.C.board is 100kHz 6kHz. 1.With the recording and playback mechanism, load the test tapes(AC-514 to TYP and AC-225 to TYP ),and set the mechanism to the recording and pausing condition in advance. 2.After setting to the recording conditions,connect 1M in series to the eraser head on the recording and playback mechanism side,and measure the eraser current from both of the eraser terminal. Standard values 100kHz +9kHz -7kHz Adjusting positions

TYP :120mA TYP :75mA

1-34

MX-J770V/MX-J880V

Diagnosis which uses extension wire method
System control P.C.board 1.Remove the metal cover and CD changer mechanism. 2.Remove the front panel assembly. 3.One screw A is removed, and relay board is removed. 4.As shown in fig.1, place the front panel assembly after opening it outward using the right side of the front panel as an axis. 5.The extension wire is connected with CN870 & CN871 on the INPUT/OUTPUT board and CN860 & CN861 on the main board. Extension wire parts No. QUQ412-4020CJ JIG-MXJ500 FLAT WIRE CONNECTOR Board x 2 FLAT WIRE CONNECTOR Board x 2 Relay board CN870 Input/output board CN871 Extension wire Main board Front panel assembly A

CN860

CN861

Relay board Fig.1

1-35

MX-J770V/MX-J880V

Flow of functional operation until TOC read
Check Point

Power ON

Play Key

Slider turns REST SW ON.

Confirm that the voltage at the pin5 of CN801 is "H"\"L"\"H".

Automatic tuning of TE offset

Check that the voltage at the

Laser ON

pin40 of IC651 is + 5V?

Detection of disc

Automatic tuning of Focus offset Confirm that the Focus error S-cuve signal at the pin28 of IC651 is approx.2Vp-p Confirm that the signal from pin24 IC651 is 0V as a accelerated pulse during approx.400ms.

Automatic measurement of Focus S-curve amplitude

Disc is rotated
Tracking error waveform at TOC reading pin 25 of IC601(TE)
Approx 1.8V VREF

Approx.3sec

Focus servo ON (Tracking servo ON) Confirm the waveform of the Tracking error signal. at the pin 25 of IC601 (R604) (See fig-1)

Automatic measurement of Tracking error amplitude
Tracking Disc to be servo braked to stop on states TOC reading finishes Automatic measurement of TE amplitude and 500mv/div automatic tuning of 2ms/div Fig.1 TE balance Tracking servo off states

Disc states to rotate

Automatic tuning of Tracking error balance

Automatic tuning of Focus error balance

Automatic tuning of Focus error gain

Automatic tuning of Tracking error gain

TOC reading

Confirm the eys-pattern at the lead of TP1

Play a disc

1-36

MX-J770V/MX-J880V

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.

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)

Is the level of RFOUT under 1.25V 0.22Vp-p?

NO

Replace it.

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.

YES O.K Play a disc.

Check the eye-pattern at TP1.

Finish.

(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.

1-37

MX-J770V/MX-J880V

Description of major ICs
AN8806SB-W(IC601) :RF&SERVO AMP
1.Pin layout
PD 1 LD 2 LDON 3 LDP 4 VCC 5 RF- 6 RF OUT 7 RF IN 8 C.AGC 9 ARF 10 C.ENV 11 C.EA 12 CS BDO 13 BDO 14 CS BRT 15 OFTR 16 /NRFDET 17 GND 18 36 PDAC 35 PDBD 34 PDF 33 PDE 32 PDER 31 PDFR 30 TBAL 29 FBAL 28 EF27 EF OUT 26 TE25 TE OUT 24 CROSS 23 TE BPF 22 VDET 21 LD OFF 20 VREF 19 ENV

2.Block diagram
6 7 29 28 27 8 9 10 17 11 12 19

+ -+

+
EQ AGC

RF DET

ENV CURCUIT

36

+

+ VCBA -

+
OFTR

13
BDO

14 15 16

35

+

VCBA

+ -

31
VCBA

+

34

+ + -+ -+

+

20

32

VCBA

+

21 33

+

++ 30 24 25 26 23 22 1 4 3

2

1-38

MX-J770V/MX-J880V

3. Pin function Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 symbol PD LD LD ON LDP VCC RFRF OUT RF IN C.AGC ARF C.ENV C.EA BDO OFTR /NRFDET GND ENV VREF LD OFF VDET TE BPF CROSS TE OUT TEFE OUT FEFBAL TBAL PDFR PDER PDF PDE PD BD PD AC I/O I O I --I O I I/O O I/O I/O O O O -O O -O I O O I O I I I I/O I/O I I I I APC amp . Input terminal APC amp . Output terminal LD ON/OFF control terminal Connect to GND Power supply RF amp . Reversing input terminal RFamp . Output terminal AGC input terminal AGC loop filter connection terminal ARF output terminal RF detection capacity connection terminal HPF-amp capacity connection terminal Capacity connection terminal for RF discernment side envelope detection BDO output terminal Capacity connection terminal for RF discernment side envelope detection OFTR output terminal RFDET output terminal Connect to GND 3TENV output terminal VREF output terminal APC OFF control terminal VDET output terminal VDET input terminal CROSS output terminal TE amp . Output terminal FE amp . Reversing input terminal FE amp . output terminal FE amp . Reversing input terminal F.BAL control terminal T.BAL control terminal I-V amp conversion resistance adjustment terminal I-V amp conversion resistance adjustment terminal I-V amp input terminal I-V amp input terminal I-V amp input terminal I-V amp input terminal Function

CS BDO I/O CS BRT I/O

1-39

MX-J770V/MX-J880V
AN7345K(IC302) PB/REC AMP

1.Block diagram

L1

L2

NF1

OUT1

EQ1

EQ CTL1 RIN1 RNF1 ROUT1 CTL

RF

VCC

24

23

22
Pre AMP

21

20

19
Pre Source CTRL

18

17
ALC AMP

16

15

14

13

REPPLE REJ

EQ
Pre AMP

CTRL

ALC AMP

ALC

1
R1

2
R2

3
NF2

4
OUT2

5

6

7

8

9

10

11
LPF

12
GND

EQ2 CTL2

RIN2 RNF2 ROUT2 LC

2. Pin Function
Pin No. 1 2 Symbol R1 R2 NF2 I/O I Function Playback amplifier input Playback amplifier input Playback amplifier negative feedback Pin No. 13 Symbol Vcc RF EQCTL I/O I Power supply Repple filter EQ control Function

I I

14

I I

3

15 16

4

OUT2 EQ2 CTL2 RIN2

O

Playback amplifier output Equlaizer Pre Amplifier input swithing time constant Recording amplifier input

ROUT1

O

Recording amplifier output

5 6

I I I

17 18

RNF1 RIN1

I I I

Recording amplifier negative feedback Recording amplifier input Pre amplifier input swithing control

7 8 9 10

19 20 21 22

CTL1

RNF2 ROUT2 LC

I O I

Recording amplifier negative feedback Recording amplifier output ALC low cut

EQ1 OUT1 NF1

I O I I

Equlayzer Playback amplifier output Playback amplifier negative feedback Playback amplifier input Playback amplifier input

11

LPF GND

I I

ALC low pass filter

23

L2

12

24

L1

I

1-40

MX-J770V/MX-J880V BA15218(IC481,501,502,526,571):OP AMP.

OUT1 1 -IN1 2 +IN1 3 VEE 4 1 + 2 + -

8 VCC 7 OUT2 6 -IN2 5 +IN2

BA3126N (IC301)
1. Terminal layout and Block diagram

1 REC SW

2 GND

3 P / B SW

4 CONT.

5 GND

6 VCC

7 P / B SW

8 GND

9 REC SW

1-41

MX-J770V/MX-J880V BA3835S (IC812) : SPI B.P.F.
1.Block Diagrams
BIASC

1 2 3 4
105Hz BPF

BIAS

18 GND

VREFC

VREF

17 16 15

AOUT

RREF

REFERENCE CURRENT

TEST

N.C.

N.C.

PEAK HOLD RES

N.C.

5 6 7 8 9
A-C

340Hz BPF

PEAK HOLD RES PEAK HOLD RES

14
MPX

N.C.

DIFOUT

1kHz BPF

13 12 11

SEL

CIN

DIF

3.4kHz BPF

PEAK HOLD RES PEAK HOLD RES

C B

10.5kHz BPF

AIN VCC

DEC

10

A

2.Pin Function No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Symbol BIASC VREFC RPEF NC NC NC CIN AIN VCC SPI-A SPI-B SPI-C SPICSB NC NC TEST AOUT GND I/O I O O O O O Function Decoupling condenser connection terminal. Decoupling condenser connection terminal. Reference resistance connection terminal. Non connect. Non connect. Non connect. Connected to GND of audio system through a condenser. Inputs the audio signal through a condenser. Power supply terminal. Output selection control terminal. Output selection control terminal. Output selection control terminal. Output selection control terminal. Non connect. Non connect. Connected to GND upon normal use. Multi-plexor output terminal. Connect to GND.

1-42

MX-J770V/MX-J880V BA3837(IC466):MIC Mixer
1.Block diagram
C 16 B 15 A 14 ROUT 13 LP 12 + LP 11 LP 10 RIN 9 - +

LOGIC

- +

R L+R SW2
- + +

SW1

L-R L

+

+ 1 VCC 2 MIC 3 LOUT 4 FK 5 TK

+ 6 LIN 7 BIAS 8 GND

2.Pin function

Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Symbol VCC MIC IN LOUT FK TK LIN BIAS GND RIN LPF1 LPF2 LPF3 ROUT CONTA CONTB CONTC

I/O I O I I I O O O O I I I

Description Power supply Microphone mixing input Channel L output Non connect Non connect Channel L input Signal bias Connect to GND Channel R input Connects to LPF time constant element Connects to LPF time constant element LPF outpout Channel R output Mode select input A Mode select input B Mode select input C

1-43

MX-J770V/MX-J880V BU1427K (IC152) : Digital RGB-TV Encoder
1. Terminal layout

2. Pin function
No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 NAME BOSD Y0/YUV0 Y1/YUV1 Y2/YUV2 Y3/YUV3 Y4/YUV4 Y5/YUV5 Y6/YUV6 GND Y7/YUV7 UV0 UV1 UV2 UV3 OSDSW CDGSWB UV4 UV5 UV6 UV7 GND NTB IM0 IM1 TEST1 TEST2 VSY HSY PIXCLK VDD IO VDD INT FUNCTION OSD BLUE DATA INPUT YUV DATA YUV DATA YUV DATA YUV DATA YUV DATA YUV DATA YUV DATA DIGITAL GROUND YUV DATA UV DATA UV DATA UV DATA UV DATA OSD ENABLE/DISABLE SELECT Video CD/CD-G UV DATA UV DATA UV DATA UV DATA DIGITAL GROND SELECT NISC/PAL MODE SELECT YUV/YUV SELECT DAC/NORMAL Normally pull down to GND SELECT U/V TIMING V-SYNC INPUT or OUTPUT H-SYNC INPUT or OUTPUT 1/2 freq. of BCLK DIGITAL VDD VDD for I/O Interlace /Non-Interlace No. 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 NAME SLABEB ADDH VREF-C CGND COUT VGND VOUT AVSS P-VDD IR AVDD YGND YOUT VDD YFILON2B YCOFF YFILON1B PAL60B VCLK RSTB CLKSW RD0 RD1 RD2 ROSD RD3 BCLK/RD4 RD5 IO VDD RD6 RD7 GOSD FUNCTION SELECT MASTER/SLAVE +0.5/-0.5 LINE at NON-INTER DAC BIAS CHROMA OUTPUT GROUND CHROMA OUTPUT Composite Output Ground COMPOSITE OUTPUT Analog Ground (DAC, VREF) POWER(DAC) VDD REFERENCE RESISTOR ANALOG (VREF) VDD Luminance Output Ground Luminance Output DIGITAL VDD Y-FILSEL THROU/FILON2 DAC(YOUT,COUT) OFF Y-FILSEL THROU/ FILON1 NORMAL/PAL60 at PALMODE Video Clock Input NORMAL/RESET SEL*1CLK/*2CLK Pull Down to GND Pull Down to GND Pull Down to GND OSD RED DATA INPUT Pull Down to GND BASE CLOCK OUT Pull Down to GND VDD for I/O Pull Down to GND Pull Down to GND OSDGREEN DATA INPUT

* The pin built-in pull-down resister. (30kohm)

1-44

MX-J770V/MX-J880V BU4094BCF(IC303,304,811):Serial to parallel port extension
1.Pin layout
STROBE DATA CLOCK Q1 Q2 Q3 Q4 Vss 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 Vdd OUTPUT ENABLE Q5 Q6 Q7 Q8 Q's Qs

2.Block diagram 2 3 8-STAGE SHIFT REGISTER 10 9

DATA CLOCK

SERIAL Qs OUTPUT

Q's

STROBE

1

8-BIT LATHES

OUTPUT ENABLE

15

3-STATE OUTPUTS Q1 Q8 PARALLEL OUTPUT

1-45

MX-J770V/MX-J880V BU9253AS(IC902) : LPF&ECHO MIX.
1.Pin layout & block diagram

COUNTER

GND ECHO VR

1 2 3

OSC

18 CR 17 MUTE 16 15 VCC 14 ADINT IN

BIAS DAINT IN DAINT OUT DALPF IN DALPF OUT MIX OUT

4 5

SRAM

D/A

A/D
-+

6 7 -+ 8

13 ADINT OUT 12 ADLPF OUT 11 ADLPF IN

MIX

9

10 MIX IN

2.Pin function Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Symbol GND ECHO VR BIAS DAINT IN DAINT OUT DALPF IN DALPF OUT MIX OUT MIX IN ADLPF IN ADLPF OUT ADINT OUT ADINT IN VCC NC2 MUTE CR I/O I I O I O O I I O O I I Descriptions Connect GND Echo level control Non connect Analog part DC bias DA side integrator input DA side integrator output DA side LPF input DAside LPF output Mix AMP output for original tone& echo tone Mix AMP input pin for original tone AD side LPF input AD side LPF output AD side integrator output AD side integrator input Power supply Non connect Mute control signal input CR pin for oscillator

1-46

MX-J770V/MX-J880V HY57V161610DTC8 or KM416S1120DT-G8 (IC504,IC505) : 16MB SDRAM
1.Block diagram
CLK CKE
Clock Generator

Mode register

Row decoder

Address

Row address buffer & Refresh counter

Bank B Bank A

Command decoder

Sense amplifier

Control logic

CS RAS CAS WE

Data counter

Latch circuit

Input & output buffer

Column address buffer & burst counter

Column decoder & latch circuit

DQM

DQ

2.Pin function Pin No. 1 2,3 4 5,6 7 8,9 10 11,12 13 14 15 16 17 18 19,20 21~24 25 Symbol VCC DQ0,1 VSS DQ2,3 VDD DQ4,5 VSS DQ6,7 VCC LDQM WE CAS RAS CS A11,10 A0~3 VCC Description Power supply Data input/output Connect to GND Data input/output Power supply Data input/output Connect to GND Data input/output Power supply Lower DQ mask enable Write enable Column address strobe Row address strobe Chip enable Address inputs Address inputs Power supply Pin No. 26 27~32 33 34 35 36 37 38 39,40 41 42,43 44 45,46 47 48,49 50 Symbol VSS A4~9 NC CKE CLK UDQM NC VCC DQ8,9 VSS DQ10,11 VDD DQ12,13 VSS DQ14,15 VSS Description Connect to GND Address inputs Non connect Clock enable System clock input Upper DQ mask enable Non connect Power supply Data input/output Connect to GND Data input/output Power supply Data input/output Connect to GND Data input/output Connect to GND

1-47

MX-J770V/MX-J880V LA1838(IC102): FM AM IF AMP&detector, FM MPX Decoder
1. Block Diagram 30 29 28
REG ALC BUFF P-DET AGC AM IF SD COMP AM S-METER FM S-METER S-CLRVE AM/FM IF-BUFF TUNING DRIVE FM IF PM DET GND STEREO DRIVE DET VCO 384KHz FF 38k FF 19k / 2 FF 19k /LS PILOT DET STEREO 5N SW AM OSC AM MIX FM RF.AMP DECODER ANIT-BIRDIE

27

26

25

24

23

22

21

20

19

18

17

16

MUTE

VCC

1
Pin No. 1 2

2

3

4

5

6

7

8

9

10

11

12

13

14

15

2. Pin Function
Symbol FM IN AM MIX I/O I Function This is an input terminal of FM IF signal. Pin No. 16 Symbol R OUT I/O O Function Right channel signal output.

O This is an out put terminal for AM mixer. I Bypass of FM IF Input of AM IF Signal.

17 18

L OUT

O Left channel signal output. Input terminal of the Right channel post AMP. Input terminal of the Left channel post AMP. Mpx Right channel signal output. Mpx Left channel signal output. Mpx input terminal FM detection output. AM detection output. This is an AGC voltage input terminal for AM This is an output terminal of voltage for FM-AFC. AM RF signal input. Register value between pin 26 and pin28 besides the frequency width of the input signal. This is a terminal of AM Local oscillation circuit. AM Local oscillation Signal output.

3

FM IF AM IF

R IN

I

4

I

19

L IN

I

5 6

GND TUNED

This is the device ground terminal. When the set is tunning,this terminal becomes "L". Stereo indicator output. Stereo "L", Mono: "H" This is the power supply terminal. FM detect transformer. This is a terminal of AM ceramic filter.

I

20 21

RO LO

O O

O

7 8 9 10

STEREO

O

22 23 24 25

IF IN

I O O I

VCC FM DET AM SD

I

FM OUT AM DET AM AGC

11

FM VSM

O

I

I

Adjust FM SD sensitivity.

26

AFC

12 13

AM VSM MUTE

O

Adjust AM SD sensitivity.

27 28

AM RF REG

I/O When the signal of IF REQ of IC121( LC72131) appear, the signal of FM/AM IF output. //Muting control input. I Change over the FM/AM input. "H" :FM, "L" : AM

O

14

FM/AM

29

AM OSC

15

MONO/ST O Stereo : "H", Mono: "L"

30 OSC BUFFER O

1-48

I

I I

MX-J770V/MX-J880V LA6541-X(IC801) : Servo Driver
1. Pin Layout & Block Diagram
Vcc
24

Vref
23

Vin4
22

Vg4
21

Vo8
20

Vo7
19

Gnd

Vo6
18

Vo5
17

Vg3
16

Vin3
15

Cd
14

Res
13

11k ohm Level shift BTL driver

Vcc + BTL driver

11k ohm Level shift

-

+

RESET

Level shift 11k ohm
1 2 3 4

BTL driver

BTL driver

Level shift 11k ohm

Regulator

5

6

7 Gnd

8

9

10

11

12

Vcc

Mute

Vin1

Vg1

Vo1

Vo2

Vo3

Vo4

Vg2

Vin2

Reg out

Reg In

2. Pin functions
Pin No.

Symbol
Vcc Mute Vin1 Vg1 Vo1 Vo2 Vo3 Vo4 Vg2 Vin2 Reg Out Reg In Res Cd Vin3 Vg3 Vo5 Vo6 Vo7 Vo8 Vg4 Vin4 Vref Vcc

Function
Power supply (Shorted to pin 24) All BTL amplifier outputs ON/OFF BTL AMP 1 input pin BTL AMP 1 input pin (For gain adjustment) BTL AMP 1 input pin (Non inverting side) BTL AMP 1 input pin (Inverting side) BTL AMP 2 input pin (Inverting side) BTL AMP 2 input pin (Non inverting side) BTL AMP 2 input pin (For gain adjustment) BTL AMP 2 input pin External transistor collector (PNP) connection. 5V power supply output External transistor (PNP) base connection Reset output Reset output delay time setting (Capacitor connected externally) BTL AMP 3 input pin BTL AMP 3 input pin (For gain adjustment) BTL AMP 3 output pin (Non inverting side) BTL AMP 3 output pin (Inverting side) BTL AMP 4 output pin (Inverting side) BTL AMP 4 output pin (Non inverting side) BTL AMP 4 output pin (For gain adjustment) BTL AMP 4 output pin Level shift circuit's reference voltage application Power supply (Shorted to pin 1)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

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MX-J770V/MX-J880V

LB1641 (IC853) : DC Motor Driver
1. Pi