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1. Remove five screws (A), and remove the top cabinet.

Top Cabinet

(A)x2

(A)x1

(A)x2

t

j

k

t

r

r

o

p

s

o

p

(F)x4

(E)x2

Main PWB

s

j

k

7. Disconnect the lead line   p  and   o   and   t   and   r   from the main

PWB under the mechanism.

8. Remove two screws (E) on both sides of the terminal angle frame.

9. Remove four screws (F) of the main PWB.

10.Disconnect the lead line   j   and   k  and   s   from the main PWB.

2. Remove two screws (B).

3. Remove one screw (C).

4. Release the hooks of the front panel at two places on both sides

and three places on the bottom, and side the front panel toward

you.

5. Disconnect the connectors  g  and  h .

6. Remove four screws (D) which installs the mechanical unit.

g

h

(D)x4

(B)x2

(C)x1

Fook x3

Fook x2

Mechanism

Front Panel

16.Remove the spacer (M).

*The spacer is bonded with both-side sticking tape.

17.Remove two screws, (N) of the decorative leg.

18.Push out the middle pin (O) of the setting leg in the direction

opposite to insertion (two places).

19.Remove one washer (P) and one nut (Q) which install the shuttle

knob.

20.Remove two screws (R) which install the power key PWB of the

front panel.

21.Remove three screws (S) which install the operate PWB of the

front panel.

11.Remove four screws (G).

12.Remove two screws (H), and remove the terminal of 21pin,

remove two connectors   m ,   n  .

13.Remove two screws (I) on both sides of the terminal angle frame.

14.Remove three screws (J) and release three hooks (K) which

install the terminal/power PWB.

15.Remove two screws (L) which install the display PWB.

f

f

m

n

m n

(I)x2

(K)x3

(J)x3

(L)x2

(G)x4

(H)x2

Terminal 
Angle Frame

Scart PWB

Display PWB

Terminal/Power 
PWB

(S)x3

(P)x1

(Q)x1

(R)x2

(M)x1

(N)x2

(O)x2

Power Key PWB

Operate PWB

<Take out disk>

1. Remove the top cabinet.
2. It is in such cases as the thin driver, and it is pushed in slowly, and a tray is drawn in the arrow direction the slide rack on the

left of the base chassis.

3. Take out disk.

Front Side

<Disassembling and assembling the mechanism chassis>

1. Remove the four base chassis mounting screws.
2. Remove the loading motor lead wire and sled motor lead wire from the main PWB.
3. To protect the pickup against breakage by static electricity, turn the base chassis over with the pickup FFC connected and short-

circuit (solder) the short land of the superposition PWB.

4. Remove the pickup FFC from the main PWB.
5. Remove the pickup FFC from the superposition PWB.
6. Remove the traverse mounting screws to remove the traverse chassis ass'y.
Note: After assembly and wiring, remove the solder joint of the short land. If short-circuited, a disk is not played back.

1. Remove the pickup FPC and loading relay FFC  A  from the main PWB.

Note: Fit the conductive rubber cap to the front end of pickup FPC (short-circuit).

2. Remove the solder joint of loading relay PWB at drive unit rear side.

1

Sled motor lead wire (Yellow·Orange)

2

IN SW lead wire 2 (White)

3

Spindle motor lead wire (Red·Black)

4

Loading motor lead wire (Red·Black)

5

Remove each lead wire from the claw.

3. Remove the relay PWB mounting screw  B  (M2.6S + 6S S tight),

and remove the relay PWB  C .

Sled Motor Lead Wire

Pickup FFC

Loading Motor Lead Wire

Traverse Fixing Screw

Superposition PWB

Pickup FFC

Short Land

<Replacing the pickup and the spindle motor>

Since the pickup optical axis and turntable inclination of DVD are adjusted with higher accuracy than of CD/MD, make a replacement
as a mechanism service chassis ass'y (refer to Parts List).

The pickup unit reads signals from the disk, and the flexible cable is connected to the board. The following signals flow through the
cable.

Focus

When electric current is flowed

FO+, FO-

from FO+ to FO-, the lens comes
 to near the disk.

Tracking

When electric current is flowed

TR+, TR-

from TR+ to TR-, the lens goes
toward the outer circumference.

FO+

TR–

TR+

FO–

ACTUATOR

OSC

V

OS

–
+
–
+
–
+
–
+

HOLOGRAM LASER UNIT

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

1

TR–

FO+

TR+

FO–

VR

PD

V

CC

GND

LD

GND

V

OS

NC

NC

V

ref

(VCC/2)

VA

VD

NC

GND

VB

VC

(NC)

Power adjust

HIGH-FREQUENCY CONVOLUTION

LD

PD

VA

VB

VC

VD

V

ref

V

cc

GND

The signal drives the tracking servo mechanism which projects the beam on the track by moving the objective lens (OL) to the outer
or inner circumference (at a right angle against the track) of the disk.

The signal drives the focus servo mechanism which aligns the focus on the pit of the disk
by elevating OL (vertically against the disk surface.)

The VR terminal is connected to GND.

2-focus objective lens

Actuator assembly

Since the laser diode largely varies output of the laser light even if the flowing current is slightly varied, the projection
light is detected with the monitor diode to control the laser light to be equally output.
Since the current varies on the monitor diode according to the intensity of the received light of the laser diode, the drive current of
the laser diode is reduced if the current of the monitor diode increases. On the contrary, the drive current of the laser diode is increased
if the current of the monitor diode decreases.
As the projection light of the laser diode becomes stronger, the current of the monitor diode increases to increase the current which
flows into the monitor diode output (PD).  This is input to the pin 44 of IC302 and is compared with the reference voltage to control
the drive current of the laser diode.
The circuit is called ALPC (Automatic Laser Power Control).

Power supply to drive the laser diode

The high-frequency convolution imposes the high-frequency signal on the DC current to impose the high frequency on the drive
current of the laser. Thus, the interference of outgoing light and reflected light is prevented.

LD

PD

Signals recorded in the disk

When the quantity of laser light increases, the
current shown in figure increases and the PD
terminal voltage rises.
IC302 is used to control. The LD terminal voltage
lowers, and the quantity of light reduces. (IC302 is
actuated by voltage input.)