JVC CHX-470-RF Service manual

SERVICE MANUAL

CD CHANGER

CH-X470RF

CH-X470RF

CH-X470RF is a combination of CH-X470 and KS-RF50.
KS-RF50 is a combination of Remote control and the RF unit.

Contents

Safety precaution
Preventing static electricity
Disassembly method
Forced eject procedures

C

O

MP

A

C

T

D

IS

C

C

H

A

N

G

E

R

1

2

–

D

IS

CH-X470

C

KS-RF50

Area Suffix

J ------ Northern America

1-2
1-3
1-4
1-20

Trouble shooting
Flow of functional
operation until TOC read
Description of major ICs

1-21

1-23
1-27

COPYRIGHT 2001 VICTOR COMPANY OF JAPAN, LTD.

No.49668

Dec. 2001

CH-X470RF

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.

1-2

CH-X470RF

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
(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 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.

Traverse mechanism PCB Ass'y

Pickup unit

Soldering

1-3

CH-X470RF

Disassembly method

Perform operations according to the items to be
disassembled.

<Replacement of the pickup>

1.

After removing the exterior (top and bottom).

2.

Proceed to the pickup replacement section.

3.

When applying grease, refer to the exploded view.
Use new grease.

<Mechanism section>

1.

Remove the exterior (required section only).

2.

The mechanism section is designed so that each unit
can be removed separately.

3.

When reassembling, refer to the assembling
precautions. (Use new grease when applying grease.)

B

B

Bottom cover

Knob

A

B

Fig. 1

B

Bottom cover

Remove A and turn in
the direction of the arrow.

BB

A

B

Knob

B

Exterior section

<

>

Removing the bottom cover and front
panel assembly

(See Fig.1 to 4)

Remove the two screw A to unlock the mounting

1.
direction knob located on the side of the main unit.

Turn the mounting direction knob in the direction of

2.
the arrow using a coin, etc. to remove it. (The knob
can be removed only when it is set to this position.)

Remove the four top cover fixing screws B at the

3.
triangle marks on the side of the main unit. (Perform
the same operation on both sides.)

Turn the unit upside down so the bottom surface is

4.
facing upward.

Lift the rear edge of the bottom cover slightly and lift

5.
the side by grasping the DIN jack section on the side
panel, then turn it toward the front (raise upward) to
remove the bottom cover.

Remove A and turn in
the direction of the arrow

The front panel can be
separated by raising the cover.

Unhook catches

Fig. 2

Fig. 3

Bottom cover

Slightly lift the jack
section to remove.

Unhook the four catches located on both sides of the

6.
front panel, and turn the front panel toward the top
cover (lower down) to remove the front panel.

1-4

Front panel

Unhook catches

Fig. 4

Removing the top cover

(See Fig.5 to 9)

Remove the four damper bracket fixing screws C to

1.
remove the damper brackets.

Pull out the dampers, being careful not to damage

2.
them.
When reattaching a damper, insert your finger to
push out the center of the damper to mount it on the
damper shaft, as shown in Fig. 6-1.

Turn the damper spring bracket toward the top at a

3.
right angle as shown in Fig. 7, then push down the
lower side of the damper spring bracket to lift it off.

Remove the three fixing screws D and E on the DIN

4.
jack board assembly.

Damper

Damper bracket

Fig. 5

CH-X470RF

Damper

Damper bracket

C

C

Lift the changer unit upward.

5.

Remove the damper springs from the mechanism

6.
chassis if required. To reassemble, refer to the
diagram below.

Apply alcohol to the shaft then immediately
attach the damper. (After attaching, check
that the shaft is correctly inserted.)

Damper shaft

Damper

Fig. 6-1

Push out with your finger
before attaching

Lift the changer unit upward

Damper

Damper bracket

C

Damper

C

Damper bracket

Fig. 6

Turn to the top position (at a right angle),
then push down to lift off.

Damper spring bracket

Fig. 7

E

Damper spring

Silver

(mechanism side)

Fig. 8

Mechanism

Chassis

How to attach the damper springs

Fig. 8-1

Damper spring

Black

(magazine side)

Remove the flexible ribbon
wire if required

DIN jack board

E

D

Fig. 9

1-5

CH-X470RF

Removing the fittings

Remove the fixing screw F.

1.

Unhook the two catches a on the top edge of the

2.

fitting, then unhook the two catches b at the left /
right bottom edges.

(See Fig.10)

Removing the main PCB assembly

(See Fig.11)

Remove the power IC fixing screw G.

1.

Remove the four screws H securing the main board

2.
assembly.

Disconnect position motor wire connector CN504

3.
from the main board assembly.

Disconnect sensor board assembly wire connector

4.
CN601 from the main board assembly.

Remove the flexible ribbon wire from CN502 on the

5.
traverse mechanism board assembly.
When reinstalling the board boards, refer to the
reassembling procedures for protecting switches, etc.

CN502

Catches b

Catches a

Fitting

H

F

Fig. 10

CN601

H

H

Main board

Fig. 11

G

CN504

1-6

CH-X470RF

<Changer mechanism section>

Sensor assembly unit

Remove the two screws I securing the sensor

1.
assembly unit.

Unhook the spring on the back of the sensor

2.
assembly unit from the holes on the chassis.

Magazine lock arm

Remove the magazine lock spring from the front side

1.
of the chassis.

Remove the poly-washer c securing the magazine

2.
lock arm.

Turn the magazine lock arm in the direction of the

3.
arrow until the notch is at the d position to remove it
from the chassis.

(See Fig.12)

(See Fig.12 and 13)

I

Spring

Sensor assembly

Rear

I

Fig. 12

Magazine lock spring

Positioning motor assembly

(See Fig.14)

Remove the two screws J securing the positioning

1.
motor.

Slightly lift the positioning motor assembly to remove

2.
it from the two burrs on the chassis.

d

Poly-washer c

Fig. 13

J

Positioning
motor assembly

Fig. 14

1-7

CH-X470RF

Rear slider

Position the unit with the front section facing down.

1.
Rotate the third gear located on the back of the main
unit in the direction of the arrow (clockwise).

Shift the rear slider in the direction of the arrow and

2.
remove it at the rear slider mounting position (at the
widest hole).

Front slider

Position the unit with the rear section facing down.

1.
Rotate the third gear located on the bottom of the
unit in the direction of the arrow (clockwise) until the
front slider is shifted to the outermost position.

Remove the E-washer securing the front slider to

2.
remove the front slider from the chassis

(See Fig.15)

(See Fig.16)

Can be removed at the stud position
(at the widest hole)

Shift

Third gear

Fig. 15

Fig. 16

Remove

Third gear

Remove the E-washer

Rear slider

Front slider

Top plate

Remove the nine screws K securing the top plate.

1.

Disconnect the section e attached to the rear of the

2.
unit, then lift the top plate slightly.

Slide the top plate toward the rear of the unit to

3.
remove the upper rod from the top plate.

(See Fig.17 and 18)

Top plate

K

K

Slide and remove the rod inside

Rod

K

Slide

Fig. 17

Top plate

Remove

1-8

K

After lifting

Fig. 18

e

CH-X470RF

Lifter unit

Unhook the elevator spring located on the front side

1.
of the unit. (Be sure to first unhook the spring from
the lifter side as shown in the upper part of the
diagram.)

Lift the lifter unit upward, then remove the lower rod

2.
to remove the lifter unit from the chassis.

Lifter bracket

Remove the two lifter bracket fixing screws L located

1.
on the back of the lifter unit.

Remove the lower rod.

2.

(See Fig.19 and 20)

(See Fig.21)

Side bracket and traverse mechanism
assembly

Remove the two side bracket unit fixing screws M to

1.
disconnect the side bracket unit from the lifter unit.

(See Fig.22)

Unhook this part first

Proper
orientation

Spring

Fig. 19

Lifter unit

Lift up the lifter unit

Lower rod

Remove the three shafts on the traverse mechanism

2.
assembly from the lifter unit.

CAUTION:

For reassembling, refer to the reassembling
procedures.

Lifter unit

M

M

Side bracket

Traverse mechanism
assembly

Remove from the
lifter unit

Fig. 20

L

Lifter bracket

L

Remove from the lifter unit

Fig. 22

Fig. 21

1-9

CH-X470RF

Removing the mechanism board / pickup
assembly (See Fig.23 to 26)

Remove the three screws N fixing the mechanism

1.
board on the back of the traverse mechanism.

Disconnect the two feed motor wires (blue and

2.
white), two spindle motor wires (red and black) and
two tray motor wires (brown and black) that are
soldered to the mechanism board.

Short-circuit the grounding point on the mechanism

3.
board. Move the mechanism board without
disconnecting the wire from connector CN501. Solder
the short circuit round on the pickup assembly.

Disconnect the wire from connector CN501 on the

4.
mechanism board.

Remove the screw O to remove the feed motor

5.
assembly.

Remove the screw P to remove the shaft holder

6.
retaining the feed slide shaft assembly and the
middle gear.

Red and black

N

Mechanism board

CN501

Brown and black

N

Blue and white

Fig. 23

Flexible wire

Move the middle gear.

7.

Move the pickup assembly upward from the gear

8.
section and remove it from the traverse chassis
assembly.

Remove the two screws Q to remove the rack arm.

9.

Pull out the feed slide shaft assembly.

10.

Remove the screw R to remove the spring.

11.

CAUTION:

To reattach the mechanism board, connect
the pickup flexible wire to connector CN501
on the mechanism board before unsoldering
the short circuit round. Subsequently, fix the
mechanism board using screws.

R

Spring

Pickup

Short circuit round

(Grounding point)

Fig. 24

Pickup assembly

Grounding point

P

Shaft holder

Feed slide
shaft assembly

Middle gear

Feed motor

1-10

Rack arm

Q

Fig. 26

Pull out

Chassis

Remove gears and
motors only when
required.

O

Fig. 25

CH-X470RF

Tray motor

Remove the two screws S securing the tray motor.

1.

Remove the two screws T to remove the tray motor

2.
assembly from the tray motor holder.

(See Fig.27 and 28)

S

S

Tray motor assembly

Fig. 27

Tray motor holder

Tray motor

Separation of the chassis (L) assembly
and chassis (R) assembly

Remove the two screws U retaining the chassis (L)

1.
and (R) assemblies.

Slide the chassis (L) assembly toward the front and

2.
detach it, then remove the chassis (L) upward.

(See Fig.29)

Slide and remove upward
as shown by the arrow

U

Front side

T

Fig. 28

U

Chassis (L) assembly

Fig. 29

Chassis (R) assembly

1-11