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Parts Code

Price Code

Name/Description

QCNW-8571GEZZ

AN

Extension cable (wire), 9pin  500mm

DVD Main CN3201–Power CN201

Extension Cable Diagram

Power PWB

CN201

Tuner

CN3201

DVD Main PWB

DVD Mechanism

F-AV PWB

VCR/DVD Display PWB

VCR Mechanism

VCR Main PWB

QCNW-8571GEZZ
9 pin

<Replacing the Pickup and the Spindle Motor>

Since the Pickup optical axis and turntable inclination of DVD are adjusted with higher accuracy, make a replacement as a
mechanism service chassis ass'y.

Front Side

Sled Motor Lead Wire

Pickup FFC

Traverse Fixing Screw

Loading Motor Lead Wire

Pickup Interface PWB

Pickup FFC

Short Land

<Take out disk>

1. Remove the mechanism with angle from the set. (refer to  33  on page 130. Remove  K , M , N )
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.

<Disassembling and assembling the mechanism chassis>

1. After setting the mechanism chassis to the angle state, ground it to prevent the electrostatic discharge damage of the pickup.
2. Remove the DVD Shield (lower)  40  (refer to the illustration on page 130).
3. Remove  P ,  Q  from the DVD Main PWB Unit  27 . (Pickup Relay FFC 58  isn't removed.) (refer to the illustration on page 130)
4. Remove screws fixing the base chassis (located at the back right and at front left when facing the set).
5. With the Pickup FFC connected, turn over the base chassis and short (solder) two short lands on the pickup interface PWB in

order to prevent the electrostatic discharge damage of the pickup.

6. Remove the Pickup FFC from the Main PWB.
7. Remove the Pickup FFC from the Pickup Interface PWB.
8. Remove the Traverse Fixing Screws to remove the Traverse Chassis ass'y.
Note: After assembling and wiring, remove the solder joint of the short land. If short-circuited, a disk is not played back.

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 IC301 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.
IC301 is used to control. The LD terminal voltage
lowers, and the quantity of light reduces. (IC301 is
actuated by voltage input.)

Video

Audio

HiFi Audio

Track

625 Monoscope

6 kHz

—

35 

µm

VROCPSV

CK

11.

JiGHMEC-M005

CK

10.

JiGDRiVER-6

BM

9.

JiGDRiVERH-4

AP

4.

Torque Driver

JiGTD1200

CB

The explanation given below relates to the on-site general service (field service) but it does not relates to the adjustment
and replacement which need high-grade equipment, jigs and skill. For example, the drum assembling, replacement and
adjustment service must be performed by the person who have finished the technical courses.

So as to perform completely the mechanism adjustment prepare the following special jigs. So as to maintain the initial
performance of the machine the maintenance and check are necessary. Utmost care must be taken so that the tape is
not damaged. If adjustment needs any jig, be sure to use the required jig.

JiGTG1200

CN

JiGMP0001

BY

1.

Torque Cassette Meter

JiGVHT-063

CZ

JiGTG0090

CM

3.

Torque Gauge Head

JiGTH0006

AW

JiGRH0002

BR

JiGSG2000

BS

JiGSG0300

BF

7.

JiGADP003

BK

Tension Gauge

These Jigs are used for checking
and adjusting the reel disk height.

When fixing any part to the threaded
hole using resin with screw, use the
jig. (Specified torque 5 kg)

This cassette torque meter is used for check-
ing and adjusting the torque of take-up for
measuring tape back tension.

These Jigs are used for checking
and adjusting the torque of take-up
and supply reel disks.

Master Plane Jig and
Reel Disk Height
Adjusting Jig

Pinch pressing force
measuring jig

This Jig is used with the tension
gauge. Rotary transformer clearance
adjusting jig.

There are two gauges used for the
tension measurements, 300 g and
2.0 kg.

This tape is especially used for elec-
trical fine adjustment.

This screwdriver is used for adjusting the
guide roller height.

For X value adjustment

This Jig is used for adjustment
of tension pole.

X value adjustment
gear driver

Tension Pole
Adjustment Driver

625 Monoscope

6 kHz

and

and

—

49 

µm

Colour bar

1 kHz

2.

Torque Gauge

6.

5.

8.

Alignment Tape

Guide roller height
adjustment driver