CASIO PZ7 Service Manual

PZ-7

(without price)

INDEX

Model-B: USA
Model-C: Europe

PORTABLE CD PLAYER

CONTENTS

Disassembly Instructions .............................................................................................................. 1

CD Adjustment ............................................................................................................................... 2

Block Diagram ................................................................................................................................ 3

Troubleshooting ............................................................................................................................. 4

PCB Views..................................................................................................................................... 11

CD Amplifier PCB Top View ..................................................................................................... 11

CD door PCB Top View............................................................................................................11

CD AMP PCB Bottom View ...................................................................................................... 12

Wiring Diagram............................................................................................................................. 13

IC Lead Identification and Internal Diagrams............................................................................. 14

Schematic Diagrams .................................................................................................................... 21

Parts List ....................................................................................................................................... 23

Exploded Views ............................................................................................................................ 29

Cabinet..................................................................................................................................... 29

CD Mechanism......................................................................................................................... 30

DISASSEMBLY INSTRUCTIONS

1. Remove five screws A holding the case assembly.

2. Remove the CD mechanism unit.

3. Remove screw B holding the CD AMP unit.

4. Remove screw C and pull out the shaft holding the CD door.

5. Remove four screws D holding the display PCB unit.

Shaft

CD door

Display PCB unit

CD mechanism unit

Upper case

CD AMP unit

Lower case

1

CD ADJUSTMENT

Precautions

To prevent damage caused by static electricity, the following procedures for grounding is requir or repairing
the unit.

Shorting tab
Desolder here

Pickup

[Note] Remove the connection after installed.

1. Wrist-Strap
for grounding

1MΩ

1MΩ

2. Conductive Sheet

Pickup

1. Grounding for the human body
Be sure to put on a wrist-strap for grounding (with impedance lower than 106 Ω) whose other end is
grounded. The strap works to drain away the static electricity build-up on the human body.

2. Grounding for the work table
Be sure to lay on the table a conductive sheet (with impedance lower than 106 Ω) such as a sheet of
copper which is grounded.

3. As static electricity build-up on clothes is not drainded away, be careful not to let your clothes touch the
unit.

4. The short-pad on the pick-up PCB of a spare part is short-circuited for protection during shipment. To
open the short circuit, remove the soldering quickly with a soldering iron whose insulation resistance is
larger than 10MΩ after connection to a suitable APC circuit.

Equipment Required

* Multi Meter
* Oscilloscope
* Compact Disc
* Dummy Load 10 kΩ

2

BLOCK DIAGRAM

3

TROUBLESHOOTING

RESUME switch off and insert a disc.
Close CD door and press PLAY button.

Is “00” flashing

on LCD ?

Yes

Is “01” displayed

after “00” flashed ?

Yes

Is the audio signal

present at the output

terminals ?

Yes

Press or key.

No

1

No

2

No

3

Can a selected

track number be searched

smoothly ?

Yes

DSG switch on.

Is there any

aufio signal present at the

output terminals ?

Yes

OK

No

4

No

5

4

Repair Item 1: At power on, “00” is not displayed.

1

Power on

Figure 1

3.2 V

Is +3.2 V lines normal ?

Yes

Is the waveform

at IC104 pin 28 like that

shown in fig. 1 ?

Yes

Does 5 MHz clock pulse

appear at IC104 pin 29 ?

Yes

* IC104 is defective.
* Check circuit around IC104 and

CN102 for loose soldering and heat
seal connecting.

No

No

No

* RESUME switch (SW101) off position.
* Q106, Q107 or Q108 is defective.
* Check circuit around IC101 and IC104.

* IC101 is defective.
* Check circuit around IC101 and IC104.

* Crystal (X102) is defective.
* IC104 is defective.
* Check circuit around IC104 and X102.

Repair Item 2: “-- --” is displayed instead of playing first song track.

2

Check how much times it takes until “-- --”
is displayed after PLAY button is pressed.

About

14 sec

Over

14 sec

A B

5

Repair Item 2-A

A

Does the LASER emit ?

Yes

Does the lens moves

up and down ?

Yes

Note: Connect GND to door switch by removing the

!

top cabinet. Than open the top cover and check the
radiation power with an optical power meter. If an
optical power meter is not available, watch the
radiation through the lens of the pickup unit at a
minimum distance of 30 cm from the pickup unit.

!

No

A1

!

No

A2

E = more than 0.9 V

Figure 2

>1.5

Figure 3

Figure 4

Load a disc and close the CD door.
Then check the following.

Is the waveform

at testpoint IRF like that

shown in fig. 2 ?

Yes

Is the waveform

at IC102 pin 1 (FEO) like that

shown in fig. 3 ?

Yes

Is the waveform

at IC102 pin 45 (TEO) like that

shown in fig. 4 ?

Yes

No

No

No

* Check flexible PCB connect.
* Check soldering for IC101, IC102 and

IC103.

* IC101, IC102 or IC103 is defective.
* Pickup is defective.

* Check circuit between IC102 pins1 and

2.

* IC102 is defective.

* Check flexible PCB connect.
* IC102 is defective.
* Check circuit around TE line.

* IC102 is defective.
* Pickup unit is defective.

6

Repair Item 2-A1: Laser does not emit.

A1

Is Q107

Base=2.8 V ?

(Play)

Yes

* Check circuit around Q107.
* Check flexible PCB connect.
* Q107 is defective.
* Pickup is defective.

No

* Check circuit around IC104 pins 1, 2 and 3.
* Check circuit around IC103 pins 7, 8 and 9.
* Check around IC102 pins 37, 36 and IC101

pin 44.

* IC102, IC103 or IC104 is defective.

Repair Item 2-A2: Object lens of pickup unit does not move up and down.

1.8 V

A2

Is the waveform

IC101 pins 26 and 27 like

that shown in fig. 5 ?

Yes

No

Is the waveform

at IC102 pin 6 (FOD) like

that shown in fig. 6 ?

Figure 5

No

Yes

Figure 6

1 V

* Pickup is defective.

* Check circuit and IC101.
* IC101 is defective.

7

* Check soldering of IC102 pin 6.
* IC102 is defective.

Repair Item 2-B

~1.1 V

B

Figure 7

When the waveform at IRF with an
osilloscope.

Is the waveform

at IC102 pin 35 like that

shown in fig. 7 ?

Yes

* Check IC103 pins 32, 34, 4, 5, 36,

37, 38, 57, 21 and circuit around
them.

* Check IC103 pins 8, 9 and 77.
* IC104 or IC103 is defective.

No

* Check soldering of C159 and IC103 pins

35 and 21.

* IC103 is defective.

8