JVC KD-SH55R, KD-SH77R Service Manual

KD-SH77R/KD-SH55R

SERVICE MANUAL

CD RECEIVER

KD-SH77R/KD-SH55R

ATT

ANGLE

AUX SEL

R D

VOLUME

KD-SH77R

KD-SH55R

E EX

Area Suffix

Continental Europe

Central Europe

Difference

point KD-SH77R KD-SH55R

Contents

RM-RK100

DVD

control

O X

LINE IN

O X

SUBWOOFER

OUT

O X

Safety precaution Preventing static electricity Disassembly method Adjustment method Flow of functional operation until TOC read Maintenance of laser pickup Replacement of laser pickup Description of major ICs

EXT OUT

O X

1-2 1-3 1-4 1-15

1-17 1-19 1-19 1-20~35

No.49634

Mar. 2001

KD-SH77R/KD-SH55R

Safety precaution

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.

Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check.

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KD-SH77R/KD-SH55R

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

Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as CD players. 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

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.

(conductive sheet) or iron plate

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

CD mechanism ass’y

Damper bracket

Attention when traverse unit is decomposed

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

1.Solder is put up before the card wire is removed from connector on the CD substrate as shown in Figure. (When the wire is removed without putting up solder, the CD pick-up assembly might destroy.)

2.Please remove solder after connecting the card wire with when you install picking up in the substrate.

Front bracket

Feed motor ass’y

FD screw

CD mechanism control board

Soldering

FD gear

Pickup unit

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KD-SH77R/KD-SH55R

Disassembly method

Removing the front panel assembly

(See Fig.1)

Press the release button in the lower right part of the front panel assembly to unlock.

Remove the front panel assembly in the direction of the arrow.

Removing the top chassis

(See Fig.2 to 6)

Turn on power.

Press the eject button in the upper left part of the front panel assembly to move the assembly as shown in Fig.2 and turn off power.

Front panel assembly

Eject button

Release button

Fig.1

Top chassis

Remove the two screws A on the upper side of the body.

Top chassis

Front panel assembly

Fig.2

Fig.3

1-4

Remove the three screws B on both sides of the body.

Remove the screw C and the three screws D on the left side of the body.

Remove the two screws E and the screw F on the back of the body.

Move the top chassis upward and remove it with the CD mechanism assembly. The connector on the CD mechanism assembly is disconnected from connector CN601 on the main board.

KD-SH77R/KD-SH55R

Top chassis

Fig.4

Top chassis

Heat sink

Fig.5

Fig.6 (KD-SH55RE)Fig.6 (KD-SH77RE)

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KD-SH77R/KD-SH55R

Removing the CD mechanism assembly

(See Fig.7)

Prior to performing the following procedure, remove the top chassis.

Remove the three screws G inside the top chassis and remove the CD mechanisma ssembly.

Removing the motor assembly

(See Fig.8 to 10)

Prior to performing the following procedure, remove the top chassis.

Disconnect the wire from connector CN703 on the main board.

Remove the motor bracket and the spring attached to the arm braket assembly (R).

Top chassis

Spring

CD mechanisma ssembly

Fig.7

Motor braket

Remove the two screws H attaching the motor bracket.

Remove the washer attaching the clutch assembly and pull out the clutch assembly from the shaft.

Remove the two screws I and the motor assembly from the motor bracket.

Motor braket

Clutch assembly

Motor assembly

Arm braket assembly (R)

Fig.8

Main board

CN703

CN601

Motor braket

1-6

Washer

Fig.10

Fig.9

Removing the main board

(See Fig.11 to 15)

Prior to performing the following procedures, remove the top chassis and the motor bracket.

Disconnect the flexible wire from connector CN701 and CN702 on the main board respectively.

Move the front bracket backward until it stops.

Remove the four screws J attaching the arm brackets (L) and (R). Move the right and arm lefter brackets from the rod gear.

Remove the rod gear.

Remove the screw K attaching the rear panel to the bottom cover on the back of the body.

Arm brackets (L)

CN701

Main board

CN702

Fig.11

KD-SH77R/KD-SH55R

Arm brackets (R)

Rod gear

Arm brackets (R)

Arm brackets (L)

Main board

Rod gear

Fig.12

Rear panel

Bottom cover

Rear panel

Bottom cover

Fig.13 (KD-SH55RE)Fig.13 (KD-SH77RE)

1-7

KD-SH77R/KD-SH55R

Remove the two screws L and move the main board backwards to release the two joints a. (The main board will be removed with the rear panel and the rear heat sink)

Remove the screw M and N attaching the rear heat sink.

Remove the two screws O and the screw P attaching the rear panel. Remove the mainboard (KD-SH55RE).

Remove the three screws O and the screw P attaching the rear panel. Remove the main board (KD-SH77RE).

Joint a

Main board

Fig.14

Rear panel

Rear heat sink

Removing the lifter switch board

(See Fig.16)

Prior to performing the following procedures, remove the top chassis, the motor bracket and the main board.

Rear panel

Lifter switch board

Fig.15 (KD-SH55RE)Fig.15 (KD-SH77RE)

Rear heat sink

Bottom cover

Remove the two screws Q attaching the lifter switch board.

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Fig.16

KD-SH77R/KD-SH55R

Removing the lifter board

(See Fig.17 to 23)

Prior to performing the following procedure, remove the top chassis assembly and thefront panel assembly.

Disconnect the flexible wire from connector CN702 on the main board.

Remove the four screws R attaching the front bracket on both sides of the body.

Push the pin of the joint c on the front of the front bracket to release the lock lever.

Main board

CN702

Front bracket

Fig.17

Front bracket

Joint c

Lock lever

Front bracket

Fig.18

Front bracket

Fig.19Fig.20

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KD-SH77R/KD-SH55R

Remove the screw S attaching the lifter board cover in the rear of the front bracket.

Release the two joints d while pushing the front side. Move the lifter board cover inthe direction of the arrow and release the eight joints e.

Joint d

Joints e

Lifter board cover

Joints e

Joint d

Remove the two screws T attaching the lifter board on the front of the body.

Joints e

Lifter board

Joint e

Front bracket

Fig.21

Lifter board cover

Fig.22

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Fig.23

KD-SH77R/KD-SH55R

Prior to performing the following procedure, remove the front panel assembly.

Removing the front board

(See Fig.24 and 25)

Remove the four screws U attaching the rear panel to the front panel assembly.

Release the eleven joints f of the front panel and the rear panel.

Disconnect the wire from connector CN503 on the front board.

If necessary, unsolder connector CN502 on the front board.

Removing the volume board

(See Fig.25 and 26)

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

Line in board

Joint f 11

Front board

Rear panel

Fig.24

Soldering

(CN502)

CN503

Fig.25

Soldering

Volume board

Remove the two screws W attaching the volume board.

Disconnect the volume knob, ring lens and volume ring from the volume board.

If necessary, unsolder the volume board.

Removing the line in board

(See Fig.25 and 27)

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

Disconnect the wire from connector CN503 on the front board.

Pull out the line in board from the front panel assembly.

Volume board

Volume lens, Volume ring

Rng knob

Fig.26

Line in board

Fig.25

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+ 25 hidden pages