Sharp CD-C612 Service Manual

CD-C612

SERVICE MANUAL

No. S3910CDC612//

CD-C612

CD-C612 mini component system consisting of CD-C612 (Main unit),
CP-C612 (Front speaker) and GBOXS0024AWM1 (rear speaker ).

• In the interests of user-safety the set should be restored to its
original condition and only parts identical to those specified be
used.

CONTENTS

Page

IMPORTANT SERVICE NOTES (For U.S.A. Only) ........................................................................................................... 2

SPECIFICATIONS ..............................................................................................................................................................2

NAMES OF PARTS ........................................................................................................................................................... 3

OPERATION MANUAL ...................................................................................................................................................... 5

QUICK GUIDE ................................................................................................................................................................... 6

DISASSEMBLY.................................................................................................................................................................. 7

REMOVING AND REINSTALLING THE MAIN PARTS................................................................................................... 10

ADJUSTMENT ................................................................................................................................................................. 10

NOTES ON SCHEMATIC DIAGRAM .............................................................................................................................. 13

WAVEFORMS OF CD CIRCUIT...................................................................................................................................... 14

BLOCK DIAGRAM ........................................................................................................................................................... 15

SCHEMATIC DIAGRAM / WIRING SIDE OF P.W.BOARD..............................................................................................18

VOLTAGE .........................................................................................................................................................................32

TROUBLESHOOTING (CD SECTION) ........................................................................................................................... 33

FUNCTION TABLE OF IC................................................................................................................................................ 38

FL DISPLAY......................................................................................................................................................................45

REPLACEMENT PARTS LIST/EXPLODED VIEW
PACKING OF THE SET (For U.S.A. Only)

SHARP CORPORATION

– 1 –

This document has been published to be used
for after sales service only.
The contents are subject to change without notice.

CD-C612

FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE REFER
TO THE OPERATION MANUAL.

IMPORTANT SERVICE NOTES (For U.S.A. Only)

BEFORE RETURNING THE AUDIO PRODUCT

(Fire & Shock Hazard)
Before returning the audio product to the user, perform the
following safety checks.

1. Inspect all lead dress to make certain that leads are not
pinched or that hardware is not lodged between the chassis
and other metal parts in the audio product.

2. Inspect all protective devices such as insulating materials,

cabinet, terminal board, adjustment and compartment covers
or shields, mechanical insulators etc.

3. To be sure that no shock hazard exists, check for leakage

current in the following manner.
* Plug the AC line cord directly into a 120 volt AC outlet.
* Using two clip leads, connect a 1.5k ohm, 10 watt resistor

paralleled by a 0.15µF capacitor in series with all exposed
metal cabinet parts and a known earth ground, such as
conduit or electrical ground connected to earth ground.

* Use a VTVM or VOM with 1000 ohm per volt, or higher,

sensitivity to measure the AC voltage drop across the
resistor (See diagram).

* Connect the resistor connection to all exposed metal parts

having a return path to the chassis (antenna, metal cabinet,
screw heads, knobs and control shafts, escutcheon, etc.)
and measure the AC voltage drop across the resistor.

VTVM

AC SCALE

1.5k ohms
10W

0.15 µ F

TO EXPOSED
METAL PARTS

All check must be repeated with the AC line cord plug connection
reversed.
Any reading of 0.3 volt RMS (this corresponds to 0.2 milliamp.
AC.) or more is excessive and indicates a potential shock
hazard which must be corrected before returning the audio
product to the owner.

TEST PROBE

CONNECT TO
KNOWN EARTH
GROUND

SPECIFICATIONS

CD-C612

General

Power source: AC 120 V, 60 Hz
Power consumption: Stand-by; 0.3 W

Power on; 50 W

Dimensions: Width; 10-5/8" (270 mm)

Height; 11-13/16" (300 mm)
Depth; 13-7/8" (353 mm)

Weight: 11.7 lbs. (5.3 kg)

Amplifier section

Output power: 20 watts minimum RMS per

channel into 4 ohms from 80 Hz
to 20 kHz, 10 % total harmonic
distortion

Output terminals: Front speakers; 5.4 ohms

Rear speakers; 16 ohms
Headphones; 16-50 ohms
(recommended; 32 ohms)

Input terminals: Video/Auxiliary (audio signal);

500 mV/47 kohms

Tuner section

Frequency range: FM; 87.5 - 108 MHz

AM; 530 - 1,720 kHz

Cassette deck section

Frequency response: 50 - 14,000 Hz (Normal tape)
Signal/noise ratio: 55 dB (TAPE 1, playback)

50 dB (TAPE 2, recording/

playback)

Wow and flutter: 0.15 % (WRMS)

Compact disc player section

Type: 3-disc multi-play compact disc

player

Signal readout: Non-contact, 3-beam semi-

conductor laser pickup

D/A Converter: 1-bit D/A converter
Frequency response: 20 - 20,000 Hz
Dynamic range: 90 dB (1 kHz)

Front speaker section

CP-C612

Type: 2-way type [5" (13 cm)

woofer and super tweeter]

Maximum input power: 30 W
Rated input power: 15 W
Impedance: 5.4 ohms
Dimensions: Width; 8-11/16" (220 mm)

Height; 11-13/16" (300 mm)
Depth; 8-3/6" (213 mm)

Weight: 6.5 lbs. (2.9 kg)/each

Rear speaker section

GBOXS0024AWM1

Type: 4" (10 cm) full range speaker
Maximum input power: 10 W
Rated input power: 5 W
Impedance: 16 ohms
Dimensions: Width; 6-3/4" (170 mm)

Height; 6-3/4" (170 mm)
Depth; 3-1/2" (88 mm)

Weight: 1.0 lbs. (0.5 kg)/each

Specifications for this model are subject to change without
prior notice.

– 2 –

CD-C612

12

4
5

6

7

8
9

10 11

15
16

12

13
14

17 18

19

31

20

21

24
25

22

26

33

27

28 29

30

32

23

35

34

3

■ Front panel

11. Disc Tray

12. Disc Skip Button

13. Open/Close Button

14.

Extra Bass Indicator

15.

FM Stereo Mode Indicator

16.

FM Stereo Indicator

17.

(CD) Repeat Indicator

18.

(CD) Play Indicator

19.

(CD) Pause Indicator

10.

Spectrum Analyzer/Volume Level Indicator

11.

(TAPE 2) Record Indicator

12.

(CD) Disc Number Indicators

13.

(CD/TUNER) Memory Indicator

14.

Timer Play Indicator

15.

Timer Record Indicator

16.

Sleep Indicator

CD-C612

NAMES OF PARTS

17.

(TAPE 2) Record Pause Button

18.

(CD) Track Down/Review Button

3

(TUNER) Preset Down Button

3

(TAPE 2) Rewind Button

19.

(CD) Track Up/Cue Button

3

(TUNER) Preset Up Button

3

(TAPE 2) Fast Forward Button

20.

Timer/Sleep Button

21.

Clock Button

22.

Timer Set Indicator

23.

Power Button

24.

Equalizer Mode Selector Button

25.

Dimmer Button

26.

Extra Bass/Demo Mode Button

27.

Function Selector Buttons

28.

Memory/Set Button

29.

(CD/TAPE) Stop Button

30.

(TAPE) Play Button

3

(CD) Play/Repeat Button

31.

Tuning and Time Up/Down Buttons

32.

Volume Up/Down Buttons

33.

Headphone Socket

34.

(TAPE 1) Cassette Compartment

35.

(TAPE 2) Cassette Compartment

– 3 –

CD-C612

■ Rear panel

11.

AC Power Input Socket

12.

FM/AM Loop Aerial Socket

13.

Video/Auxiliary (Audio Signal) Input Sockets

14.

Rear Speaker Terminals

15.

Front Speaker Terminals

CP-C612

■ Front speaker

11.

Super Tweeter

12.

Woofer

13.

Bass Reflex Ducts

14.

Speaker Wire

GBOXS0024AWM1

■ Rear speaker

11.

Full-Range Speaker

12.

Speaker Wire

2

1

5

4

3

1

2

4

3

1

■ Remote control

11. Remote Control Transmitter LED

● CD control section

12. Disc Number Select Buttons

13. Memory Button

14. Pause Button

15. Clear Button

16. Track Down/Review Button

17. Track Up/Cue Button

18. Disc Skip Button

19. Play/Repeat Button

10. Stop Button

11. Random Button

● Tuner control section

12. Preset Up/Down Buttons

● Tape control section

13. (TAPE 1) Play Button

14. (TAPE 2) Record Pause Button

15. (TAPE 1/2) Stop Button

16. (TAPE 2) Play Button

17. (TAPE 2) Rewind Button

18. (TAPE 2) Fast Forward Button

● Common section

19. Equalizer Mode Selector Button

20. Function Selector Buttons

21. Power Button

22. Extra Bass Button

23. Volume Up/Down Buttons

2

1

2
3

4
5

6
7

16 17 18

13 14

15

19
20

21 23
22

8
9

10
11
12

– 4 –

OPERATION MANUAL

SETTING THE CLOCK

1

Press the POWER button to enter the stand-by mode.

2

Press the CLOCK button.

3

Within 5 seconds, press the MEMORY/SET button.

4

Press the TUNING/TIME ( or ) button to select the time

display mode.

"AM 12:00" → The 12-hour display will appear.

(AM 12:00 - PM 11:59)

"AM 0:00 " → The 12-hou r display will appear.

(AM 0:00 - PM 11:59)

"0:00" → T he 24-hour d isplay wil l appear.

(0:00 - 23:59)

● Note that this can only be set when the unit is first installed

or it has been reset (see page 17).

5

Press the MEMORY/SET button.

6

Press the TUNING/TIME ( or ) button to adjust the hour.

● Press the TUNING/TIME ( or ) button once to advance

the time by 1 hour. Hold it down to advance continuously.

● When the 12-hour display is selected, "AM" will change auto-

matically to "PM".

7

Press the MEMORY/SET button.

8

Press the TUNING/TIME ( or ) button to adjust the

minutes.

● Press the TUNING/TIME ( or ) button once to advance

the time by 1 minute. Hold it down to change the time in 5

minute intervals.

● The hour setting will not advance even if minutes advance from

"59" to "00".

9

Press the MEMORY/SET button.

● The clock starts operating from "0" seconds. (Seconds are not

displayed.)

Note:

● In the event of a power failure or when the AC power cord is

disconnected, the clock display will go out.

When the AC power supply is restored, the clock display will

flash on and off to indicate the time when the power failure

occurred or when the AC power cord was disconnected.

CLOCK

POWER

MEMORY/

SET

TUNING/

TIME

( )

AM 12:00 AM 0:00 0:00

2

3

4

7

6

5

8

9

If this happens, follow the procedure below to change the clock

time.

To change the clock time:

①

Press the CLOCK button.

②

Within 5 seconds, press the MEMORY/SET button.

③

Perform steps 6 - 9 above.

To see the time display:

Press the CLOCK button.

● The time display will appear for about 5 seconds.

To change the time display mode:

①

Perform steps 1 - 2 in the section "RESETTING THE

MICROCOMPUTER"

②

Perform steps 1 - 9 above.

(Main unit operation)

In this example, the clock is set for the 12-

hour (AM 12:00) system.

RESETTING THE MICROCOMPUTER

Reset the microcomputer under the following conditions:

● To erase all of the stored memory contents (clock and timer

settings, and tuner and CD presets).

● If the display is not correct.

● If the operation is not correct.

1

Press the POWER button to enter the stand-by mode.

2

While pressing down the button and the but -

ton, hold down the POWER button for at least 1 second.

Caution:

● The operation explained above will erase all data stored in

memory including clock and timer settings, and tuner and CD

presets.

2

1,2

CD-C612

– 5 –

CD-C612

MINI COMPONENT SYSTEM

Quick Guide/Guía rápida

CD-C612

● Remote control x 1

●

Controlador remoto x 1

● 2 “AA” batteries

●

Dos pilas “AA”

Remote Sensor

Sensor remoto

2

Preparation for use /

Preparación para su uso

1

Check the supplied accessories /

Compruebe los accesorios suministrados

● FM/AM loop antenna x 1

●

Antena de cuadro de

FM/AM x 1

● Batteries are not included.

●

Las pilas no están incluidas.

8” - 20’ (0.2m - 6m)

0,2m - 6m

■ Speaker connection

■

Conexión de los altavoces

■ Antenna connection

■

Conexión de las antenas

Rear speaker (Right)

Altavoz trasero (Derecho)

Rear speaker (Left)

Altavoz trasero (Izquierdo)

Front speaker (Right)

Altavoz delantero

(Derecho)

Front speaker (Left)

Altavoz delantero

(Izquierdo)

● AM Loop Antenna

●

Antena de cuadro

de AM

● FM Antenna

●

Antena de FM

● AC 120 V, 60 Hz

●

120 V de CA, 60 Hz

■ Turning the power on and off

■

Conexión y desconexión de la alimentación

■ Remote control

■

Controlador remoto

POWER

POWER

Red

Rojo

Red

Rojo

Wire with the

white line

Cable con la

línea blanca

Wire with the

white line

Cable con la

línea blanca

● AC power cord x 1

●

Cable de alimentación

de CA x 1

Black

Negro

15

15

3

Listening to a CD /

Audición de discos CD

4

Listening to a tape /

Audición de una cinta

5

Listening to the radio /

Audición de la radio

6

Recording from CDs /

Grabaciones de discos CD

7

Sound control /

Control del sonldo

● Label facing up

●

Etiqueta hacia arriba

■ To stop the playback

■

Para detener la reproducción

■ To stop the playback

■

Para detener la reproducción

● Load the disc to be

recorded.

●

Introduzca el disco

que va a grabar.

● CD recording

starts.

●

La grabación de

CD empieza.

■ Volume

■

Volumen

■ Extra bass (X-BASS)

■

Graves extra (X-BASS)

■ Pre-programmed equalizer

■

Ecualizador preprogramado

VOLUME

FLAT

HEAVY-1 HEAVY-2

SOFT-2

SOFT-1 VOCAL

■ To stop the playback

■

Para detener la reproducción

TAPE 1

TAPE 2

TAPE 2

– 6 –

DISASSEMBLY

Caution on Disassembly

Follow the below-mentioned notes when disassembling
the unit and reassembling it, to keep it safe and ensure
excellent performance:

1. Take cassette tape and compact disc out of the unit.

2. Be sure to remove the power supply plug from the wall
outlet before starting to disassemble the unit.

3. Take off nylon bands or wire holders where they need to
be removed when disassembling the unit. After servicing
the unit, be sure to rearrange the leads where they were
before disassembling.

4. Take sufficient care on static electricity of integrated
circuits and other circuits when servicing.

CD-C612

STEP REMOVAL PROCEDURE FIGURE

1 Top Cabinet 1. Screw ..................... (A1) x4 7-1

2 Side Panel 1. Screw ..................... (B1) x6 7-1

(Left/right) 2. Hook....................... (B2) x2

3 CD Player Unit/ 1. Turn on the power supply, 7-2

CD Tray Cover open the disc tray, take out

the CD cover, and close.
(Note 1)

2. Hook....................... (C1) x3

3. Hook....................... (C2) x2

4. Socket .................... (C3) x2

4 Back Board 1. Screw ..................... (D1) x4 7-2

5 Main PWB 1. Screw ..................... (E1) x10 8-1

Display PWB/ 2. Bracket ................... (E2) x2

Switch PWB 3. Socket .................... (E3) x5

Headphones PWB

6 Front Panel 1. Screw ..................... (F1) x2 8-1

7 Tape Mechanism 1. Open the cassette holder. 8-2

8

CD Servo PWB

(Note 2) 2. Socket .................... (H2) x4

9 Turntable 1. Screw ..................... (J1) x1 8-4

10 Disc Tray 1. Screw ..................... (K1) x2 8-4

11 CD Changer 1. Screw ..................... (L1) x4 9-1

Mechanism

12 CD Mechanism 1. Screw ..................... (M1) x1 9-1

Note 1:

How to open the changer manually. (Fig. 7-3)

1. Turn fully the lock lever in the arrow direction through the
hole on the loading chassis bottom in this state.

After that, push forward the CD player base.

Note 2:

1. After removing the connector for the optical pickup from the

connector, wrap the conductive aluminium foil around the
front end of connector to protect the optical pickup from
electrostatic damage.

4. Hook....................... (E4) x2

2. Hook....................... (F2) x2

2. Screw...................... (G1) x6

1. Screw ..................... (H1) x1 8-3

2. Stabilizer ................ (J2) x1

2. Guide ..................... (K2) x2

Hook
(B2)x1

(B1)x1
ø3x10mm

(B1)x2
ø3x12mm

CD Servo
PWB

Disc Tray

CD Player
Unit

(D1)x4
ø3x10mm

CD-C612

(A1)x2
ø3x12mm

Side Panel
(Right)

(C3)x2

1

1

Lock Lever

Back Board

Hook
(C2)x1

Pull

Back Board

Top Cabinet

(B1)x2
ø3x12mm

Figure 7-1

Hook
(C1)x3

Figure 7-2

(B1)x1
ø3x10mm

Main PWB

Hook
(B2)x1

CD Tray Cover

Front Panel

CD-C612

Front Panel

(A1)x2
ø3x12mm

Side Panel
(Left)

2

Hook

(C2)x1

Pull

Figure 7-3

– 7 –

CD-C612

Headphones
PWB

(E1)x1
ø3x10mm

(E1)x1
ø3x10mm

(E3)x1

(E1)x8

(E2)x1

ø3x10mm

Main
PWB

(E3)x3

Tape
Mechanism
PWB

Switch PWB

Hook
(F2)x1

Figure 8-1

Display PWB

(E3)x1

Front Panel

Hook
(E4)x2

Hook
(F2)x1

Tape
Mechanism

(F1)x2
ø3x10mm

(E2)x1

(H2)x2

(H2)x2

(H1)x1
ø3 x10mm

CD Servo
PWB

CD Player Unit

Figure 8-3

(J1)x1
ø3 x10mm

(J2)x1

(G1)x6
ø3x10mm

Front Panel

Cassette
Holder
(Left/Right)

Open

Tape
Mechanism

Washer

Turntable

Disc Tray

(K1)x1
ø3 x10mm

(K2)x1

(K1)x1
ø3 x10mm

CD Player Unit

(K2)x1

Figure 8-4

Figure 8-2

– 8 –

CD-C612

(M1)x1
ø2.6 x10mm

CD Player Base

Shift Lever

CD Mechanism

(L1)x4
ø3 x12mm

CD Changer
Mechanism

Be careful when installing the CD changer mechanism.
Install the CD changer mechanism on the CD player base after
the shift lever has been set in the highest position.

Figure 9-1

CP-C612

STEP REMOVAL

1 Front Speaker 1. Front Panel ............ (A1) x1 9-1

2. Tip .......................... (A2) x2

3. Screw ..................... (A3) x4

PROCEDURE

FIGURE

Note:

The rear speakers can be easily disassembled.
Therefore the disassembling method is not discribed.
For details refer to the disassembling drawing in the Parts
Guide.

CP-C612

Front Panel

(A1)x1

Piezo

(A3)x4
ø4x12mm

Woofer

Figure 9-2

(A2)x2

Screw Driver

– 9 –

CD-C612

REMOVING AND REINSTALLING THE MAIN PARTS

CD MECHANISM SECTION

Perform steps 1, 2, 3 and 8-12 of the disassembly method to
remove the CD mechanism.

How to remove the loading motor
(See Fig. 10-1)

1. Remove the screws (A1) x 2 pcs., to remove the loading
motor.

Loading / Up
/ Down Motor

Motor
PWB

( A1 ) x2
ø2.6 x5mm

Figure 10-1

How to remove the pickup (See Fig. 10-2)

1. Remove the screws (B1) x 2 pcs., to remove the shaft (B2).

2. Remove the stop washer (B3) x 1 pc., to remove the gear
(B4).

3. Remove the pickup.

Note

After removing the connector for the optical pickup from the
connector, wrap the conductive aluminium foil around the
front end of connector to protect the optical pickup from
electrostatic damage.

ADJUSTMENT

MECHANISM SECTION

• Driving Force Check

Torque Meter

Play: TW-2412 Tape 1: Over 80 g

• Torque Check

Torque Meter

Tape 1

Play: TW-2111 30 to 60 g. cm 30 to 60 g.cm
Fast forward: TW-2231 — 60 to 120 g.cm
Rewind: TW-2231 — 60 to 120 g.cm

Specified Value

Tape 2: Over 80 g

Specified Value

Tape 2

( B1 ) x2
ø2.6 x6mm

Stop Washer
( B3 ) x1

Pickup

Shaft
( B2 ) x1

Gear

CD Mechanism

( B4 ) x1

Figure 10-2

• Tape Speed

Test Tape

Normal MTT-111 Volume in 3,000 ± Speaker
speed motor. 30 Hz terminal

Adjusting

Point

(MM1) (Load

TAPE MECHANISM

Specified

Value

MM 1
Motor

Instrument

Connection

resistance:
8 ohms)

Volume in motor

– 10 –

TUNER SECTION

fL: Low-range frequency
fH: High-renge frequency

• AM IF/RF

Signal generator: 400 Hz, 30%, AM modulated

Test Stage

IF 450 kHz 1,720 kHz T351 *1
Band — 530 kHz (fL): T333 *2

Coverage 1.1 ± 0.1 V
Tracking 990 kHz 990 kHz (fL): T331 *1

Frequency Frequency

Display

*1. Input: Antenna, Output: TP302
*2. Input: Antenna, Output: TP301

Setting/

Adjusting

Parts

Instrument

Connection

CD-C612

• VCO Frequency

Frequency

98.00 MHz 98.00 MHz VR351* Pin 13, Pin 21
(60 dB) and ground

Frequency

Display

* Adjust for 76 kHz ± 200 Hz.

Notes:

After preparing the test circuit shown in Fig 11-2, connect the
Pin 13 , Pin 21 and ground of the IC303 with test circuit, and
measure the Value.
At this time, apply a standard unmodulated signal input and
adjust the VCO.

Adjusting

Parts

Instrument

Connection

of IC303

• FM RF

Signal generator: 1 kHz, 75 kHz dev., FM modulated

Test Stage

Band — 87.50 MHz L303(fL): *1
Coverage 3.4 V ± 50 mV

RF 98.00 MHz 98.00 MHz L302 *2

Frequency

(10-30 dB)

Frequency

Display

Serring/

Adjusting

Point

Instrument

Connection

*1. Input: Antenna, Output: TP301
*2. Input: Antenna, Output: Speaker terminal

• Detection

Signal generator: 10.7 MHz, FM sweep generator

Test

Stage

Detection 10.7 MHz 98.00 MHz T352 Input: Pin 1 of

IF 10.7 MHz 98.00 MHz T301(Turn Input: Pin 1 of

Frequency

Frequency

Display

Adjusting

Parts

the core of IC301
transformer Output: TP302
T352 fully
counter­clookwise.)

Instrument

Connection

IC303
Output: TP302

CD ERROR CODE DESCRIPTION

When a malfunction occurs during CD operation, an error
code will be displayed to identify the function in CD operation
which failed.

Error State Code
0001 Cannot detect puin SW
0101 Tray close operation error
0105 Tray close operation error
0201 Tray open operation error
0203 Tray open operation error
0304 Disc skip operation error
0305 Disc skip operation error

0307 Disc skip operation error

11

IC302

12

TP302

C356

VR351

VCO

Figure 11-1 ADJUSTMENT POINTS

Pin 13 of IC303

G

1

FM Band
Coverage
fL

22

L303

T351

CF351

12

IC303

13

21

MAIN PWB

Pin 21 of IC303

FET : 2SK19 or 2SK54

D

S

10 kΩ

Figure 11-2

IC301

9

T301

FM IF

TP301

AM IF

CF301

1

24

AM Band
Coverage fL

1

L302

FM RF

BF301

CNP301

R361

AM Tracking
fL

T333

T352

FM DET

TO FREQUENCY
COUNTER

T331

– 11 –

CD-C612

1 2 3

TEST MODE

• Setting the test mode

Any one of test mode can be set by pressing several keys as follows.
<REC. PAUSE> + <DISC. SKIP> + <POWER> TEST: CD operation test

• TEST mode

Function — CD test mode

Setting of TEST mode
Indication of CD TST mode (Fig. 12-1)
OPEN/CLOSE operation is manual operation.
The pickup can be moved by using the (

<MEMORY>
LASER ON

<MEMORY>
Tracking on the spot.
SERVO OFF PLAY

) or ( ) key.

<MEMORY>
Tracking on the spot.
SERVO ON PLAY

IL is not performed.

<STOP>

STOP

<PLAY> key input

TOC. IL is performed, and the ordinary PLAY is performed.
If the following key is pressed during PLAY, it is possible
to specify directly any Track No.
<Disc Number 1> key: Track 4
<Disc Number 2> key: Track 9

Press <STOP> key.

Stop

<Disc Number 3> key: Track 15

Note:

Only in STOP state it is possible to slide the pickup with the ( ) or ( ) key.
VOL. --- Last memory

BAL. --- CENTER
R.GEQ. --- FLAT
X-BAS --- OFF

Canceling method - POWER OFF

Figure 12-1

CD SECTION

Since this CD system incorporates the following automatic adjustment function, when the pickup is replaced, it is not necessary
to readjust it.
Since this CD unit does not need adjustment, the combination of PWB and laser pickup unit is not restricted.

• Automatic adjustment item

1. Focus offset (Fig. 12-2)

2. Tracking offset (Fig. 12-3)

3. E/F balance (tracking error balance) (Fig. 12-4)

4. RF level AGC function (HF level: constant)

5. RF level automatic follow-up of the tracking gain

This automatic adjustment is performed each time a disc is changed. Therefore,
each disc is played back using the optimal settings.

0.1s

0.50 V
IC1 20 FE

0.1s

0.50 V
IC1 7 TE

Figure 12-2

200 ms
1V/diV
IC 1 15

TO

200 ms
1V/diV
IC 1 7

TE

Figure 12-4

FOCUS
OFF-SET
ADJUST

TRACKING
OFF-SET
ADJUST

1
2

TRACKING/
ERROR
BARANCE

1

ADJUST

2

– 12 –

10ms

0.50 V
IC1 20 FE

10ms

0.50 V
IC1 7 TE

Figure 12-3

Enlarged
View

TRACKING
OFF-SET
ADJUST

1
2

NOTES ON SCHEMATIC DIAGRAM

• Resistor:
To differentiate the units of resistors, such symbol as K and
M are used: the symbol K means 1000 ohm and the symbol
M means 1000 kohm and the resistor without any symbol is
ohm-type resistor. Besides, the one with “Fusible” is a fuse
type.

• Capacitor:
To indicate the unit of capacitor, a symbol P is used: this
symbol P means micro-micro-farad and the unit of the
capacitor without such a symbol is microfarad. As to
electrolytic capacitor, the expression “capacitance/withstand
voltage” is used.
(CH), (TH), (RH), (UJ): Temperature compensation
(ML): Mylar type
(P.P.): Polypropylene type

• Schematic diagram and Wiring Side of P.W.Board for this
model are subject to change for improvement without prior
notice.

CD-C612

• The indicated voltage in each section is the one measured
by Digital Multimeter between such a section and the chas­sis with no signal given.

1. In the tuner section,

( ) indicates AM
< > indicates FM stereo

2. In the main section, a tape is being played back.

3. In the deck section, a tape is being played back.

( ) indicates the record state.

4. In the power section, a tape is being played back.

5. In the CD section, the CD is stopped.

• Parts marked with “ ” ( ) are important for
maintaining the safety of the set. Be sure to replace these
parts with specified ones for maintaining the safety and
performance of the set.

REF. NO DESCRIPTION POSITION POSITION

SW1 OPEN/CLOSE ON—OFF
SW2 MECHA UP ON—OFF
SW3 DISC NUMBER ON—OFF
SW4 PICKUP IN ON—OFF
SW701 POWER ON—OFF
SW703 CLOCK ON—OFF
SW704 TIMER/SLEEP ON—OFF
SW708 DISC SKIP ON—OFF
SW709 OPEN/CLOSE ON—OFF
SW710 REV ON—OFF
SW711 REC PAUSE ON—OFF
SW712 MEMORY/SET ON—OFF
SW713 STOP ON— OFF
SW714 TUNER/BAND ON—OFF
SW715 VIDEO ON—OFF

FRONT

VIEW

REF. NO DESCRIPTION

SW716 TAPE ON—OFF
SW717 CD ON—OFF
SW722 FF ON—OFF
SW723 TUNING UP ON—OFF
SW724 TUNING DOWN ON—OFF
SW725 PLAY ON—OFF
SW726 VOLUME DOWN ON—OFF
SW727 VOLUME UP ON—OFF
SW728 X-BASS/DEMO ON—OFF
SW729 EQUALIZER ON—OFF
SW730 DIMMER ON—OFF
SWM 3 FOOL PROOF ON—OFF
SWM 4 F.A.S. ON—OFF
SWM 5 CAM ON—OFF

FRONT

VIEW

E C B
(S)(G)(D)
(1) (2) (3)

KRA102 M
KRA109 M
KRC102 M
KRC104 M
KRC107 M
KTA1271 Y
KTA1273 Y
KTC3203 Y

B C E
(D)(G)(S)
(3) (2) (1)

KTC3200 GR

2SA1318
2SC3331
2SA1015GR
2SC535C
KTA1274 Y
KTD2058 Y

Figure 13 TYPES OF TRANSISTOR AND LED

– 13 –

1 2 3

SVC211C
SVC348S

FRONT

VIEW

SLI342UCJ1

CD-C612

1

2

5ms

0.50 V
IC1 20 F.E

5ms

5.0 V
IC1 54 DRF

WAVEFORMS OF CD CIRCUIT

STOP PLAY

FOCUS SERCH

0.5ms

6

10.0 V
JP+

0.5ms

7

10.0 V
JP-

0.5ms

8

0.50 V

3
1

JP

0.5ms

9

1.00 V
TE

0.5ms

3

1.00 V
HF

0.5ms

4

5.0 V
HFL

0.5ms

5

5.0 V
TES

0.5ms

1.00 V

3

HF

0.5ms

4

5.0 V
HFL

0.5ms

5

5.0 V
TES

50ms

6

10.0 V
JP+

50ms

7

10.0 V
JP-

50ms

8

0.50 V
JP

50ms

9

1.00 V
TE

CUE

1
2

3

REVIEW

1
2

3

CUE

10

11

10

11

12

20ms

1.00 V
SPO

20ms

2.00 V
CLV+

50ms

1.00 V
SPO

50ms

2.00 V
CLV+

5s
100mV
SLD

PLAY

NORMAL DISC
TN0=01

PLAY

TCD-712 (140mm)
TN0=01

PLAY

TCD-712

0.5ms

10.0 V

6

JP+

0.5ms

10.0 V

7

JP-

0.5ms

0.50 V

8

JP

0.5ms

9

1.00 V
TE

50ms

10.0 V

6

JP+
50ms

10.0 V

7

JP­50ms

8

0.50 V
JP

50ms

9

1.00 V
TE

REVIEW

– 14 –

12

0.5s
100mV
SLD

1

1

CD-C612

+B1

+5V

TO MAIN SECTION

(TO IC601)

2

43
41
36
23

5
6

+7V

XVDD
RVDD
LVDD
VDD

ISET

VVDD

1

40

RCHO

56

4

3

38

36

37

LVSS

LVDD

LCHO

IC2

LC78622N

SERVO/SIGNAL

44

XOUT

CONTROL

CNP11

SWITCHING

REGULATOR

Q51

27

39

RVSS

CONT4

24 25

CONT1

CONT3

CONT2

26

58

53

TO DISPLAY

SECTION

M3

TURNTABLE

UP/DOWN

LOADING

SW2

MECHA UP

SW3

SW1

OPEN/CLOSE

DISC NUMBER

MOTOR

M

–

+

SOLM2

SOLENOID

10

CNS10

CNP10

~

9

GND (D)

10

9

7

8

6

MECHA UP

GND (D)

DISK NO.

OPEN/CLOSE

7

8

6

5

4

GND (D)M–M+

5

4

2

3

1

SOL–

SOL+

2

3

1

Q52

+4.3V

+5V

Q1

LASER DRIVER

XL1

16.93MHz

VOLTAGE

REGULATOR

45

64

62

XIN

VCC1

LD0

EFMO

EFMIN

CLV+

~

10

12

9

~

32 40 4344

JP–

SLC

CV+

IC1

LA9241M

SERVO AMP.

FIN1EF

FIN2

2

3

1

/RES. /CQCK. COIN

JP–

20

CE

SL1

DAT

DRF

SL+
SL–

SLD

SP

SPO

FD
TO

4

SQOUT. RWC. WRQ

CL

53
52
51

54
31
30

29
23
27

16

15

CL, DAT, SELIAL CONTROL/CE

SL+. SL–. DRF

25
20
17

TRACKING/

2

1

6

M2

SLED

MOTOR

M1

SPINDLE

MOTOR

+B1

+B5

18244020

IC3

M63001FP

FOCUS/

SPIN/SLED

DRIVER

45

15

7

M

M

3839284142 37 36

16 26

27

23
35

~

29
22

21

14

~

8

PICKUP IN

PU-IN SW

SW4

PICKUP UNIT

FOCUS COIL

TRACKING COIL

Figure 15 BLOCK DIAGRAM (1/3)

– 15 –

CD-C612

O

FM

ANTENNA

AM LOOP
ANTENNA

BF301

FM B.P.F

T331 T333

1 3 1

2 3 4

AM TRACKING

IC301

TA7358AP

FM FRONT END

5

7

FM

OSC

FM RF

L302

OSC BUFF

AM BAND
COVERAGE

8

L303

Q302

6

9

FM OSC

FM IF FM IF

T301

VT

FM +B

CF301

FM IF IN

FMOSC

20

Q344

SWITCHING

+B4

AM IF AMIF

T351

1 3

AM MIX

FM/AM IF MPX.

24

23

AM OSC IN

X352

4.5MHz

22

1

OSC

PLL (TUNER)

7

FM

CF351

IC303

LA1805

22

AM+B

AM RF IN

FM IN

AM IN

16

15

IC302

LC72131

10

+B4

T352

FM DET

21

5

6

GND AM IF

7

STEREO

11

20

FM DET

FM+B MO/ST

+B7

DODICL

CE

3 4

6

5

21

FOOL PROOF

SOLENOID

VR351

MPX VCO ADJ

FM/AM
SWITCHING

VOLTAGE

REGURATER

17

SWM3

SWM4

F.A.S

SOLM1

SWM5

CAM

MON

15

13

VCO

L

9

10

R

FM/AM

11

Q343

IC704

3

1

2

+B4

FROM CD SECTION
CNP11

TAPE 1

PB HEAD

TAPE 2

REC PB HEAD

L-CH
R-CH

L-CH

R-CH

ERASE
HEAD

REC

P.B

AC BIAS

CNS11

1
2
3

SWITCHING

Q103~Q106

IC101

PLAYBACK AND RECORD

L(T1)

R(T1)

L(T2)

R(T2)

L NF

R NF

POP REDUCE

L REC
R REC

SWITCHING SWITCHING

Q107
Q108

BIAS
OCS

Q128
L104

AN7345K

/PLAYBACK AMP.

1

24

2

23

3
4

T1/T2

6

REC

9

16
14

REF

12

NOR/
HIGH

15 19

Q109

SWITCHING

Q111

P.B.

H/N

T1/T2

13

4

21

5

20

7

18

8

17
10

Q110

L
R

L R REC

L NF
R NF
ALC

+B4

PB

JK601

VIDEO

L

R

SWITCHING

Q124
L103

AUX
TAPE

TUNER

CD

11

5

L

16

R

4

L

17

R

3

L
R

18

AUDIO PROCESSOR

L

2

R

19

1

BAIS

Q126

10

IC601

M62439SP

9

20

Q121
Q122

MUTING

13

8

Figure 16 BLOCK DIAGRAM (2/3)

– 16 –

J

MONO/ST

15

/ST

L

10

R

AM

43

04

3

B4

CD-C612

FL701

DISPLAY

Q702

M

Q703

MM1

TAPE MOTOR

9

50
49
48
47

+B7

46

VDD

45
44

3

KEY
SW701,
SW703,704,
SW708~717,
SW722~730

43
42
41
40
39
38
37
36
35
34
33
32
31

LED722

+B7

1

RX701

2

+B7

~~~

1 2 3

4

535251

AVDD

282930

+B5

PHM1

15 2516

28

26

29

IC701

IX0280AW

SYSTEM CONTROL

MICROCOMPUTER

VDD

+B7

~

36

XL701

4.19MHz

37 3839

7170696867666564636261 80797877

737260595857565554

101112131415161718192021222324252627

8

9

Q704

Q705
Q706
Q707

767574

6

5

7

4 3 2 1

81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100

VDD

TO CD
SECTION

MEMORY
BACK UP

UNSWITCH
+B7

–B4

IC961

R

13

8

L

R

REC

T1/T2

ZD801

Q601
Q602

Q603
Q604

+B1

+B4

+B5

+B2

+7.3V

+12V(ANALOG)

+12V(MOTOR)

+5.6V

+B6

Q821

+5V

13

9

VOLTAGE

REGULATOR

Q822

REGULATOR

Q824

REGULATOR

Q823

REGULATOR

LA4451
POWER AMP.

+B

3

4

7

VOLTAGE

D803~D806

VOLTAGE

VOLTAGE

Q801

D801

D807
~D809

Q802

FRONT
2
5

L-OUT

R-OUT

F803

4A/125V

F805

2A/250V

T801

POWER

TRONSFORMER

T.F

JK970
HEADPHONES

SO961
SPEAKER
TERMINAL

REAR
SPEAKER

FRONT
SPEAKER

RL801

AC POWER
SUPPLY CORD

AC 120V 60Hz

BAIS

UNSWITCH

+B7

Q803

Figure 17 BLOCK DIAGRAM (3/3)

– 17 –

D810~D813

T802

POWER

TRONSFORMER

CD-C612

0

0

2

D

C

DRF (ASP)

A

CNS1B

K
E
A
B

B

C

D

E

F

G

F

SPINDLE

MOTOR

MOTOR

SW4

PICKUP IN

5
4

2
1

PICKUP UNIT

5

K

4

E

3

A

2

B

1

F

1
2
3
4
5
6
7
8

CNS2B

1
2
3
4

5

6

7
8

CD MOTOR
PWB-C

M1

+

M

–

+

M2

SLID

M

–

CNS1A

1M

TR–
TR+
FO+
FO–
GND
PD
VR
LD

SPIN

SLIDE

PU-IN

1
2
3
4
5

1/16

1M

2200P

ACTUATOR

6
5
4
3
2
1

1
2
3 3
4
5

CNP1

2200P

TR+
FO+

FO–
TR–

CNS2A

1
2
3
4
5
6

7

8

CNP3A

CNS3B

6
5
4
3
2
1

R2
1K

C15

0.01

K
A
B
E
F

PD

TR–

1

TR+

2

FO+

3

FO–

4

GND

5

PD

6

VR

7

LD

LD

8

CNP2

CNP3

CNS3A

6

6

5

5

4

4

3

3

2

2

1

1

C2

0.01

0.1/50

TE

C54

0.001
R11

6.8K

R13

1K

R14
27K

C12

0.1

TR–
TR+
FO+
FO–

CD_GND

C36

100/16

C55

100/16

SP+
SP–
SL_+
SL_–

CD_PUIN

C1

47/16

Q1

2SA1318

LASER DRIVER

C4

R9

100K

R10

0.033

2.2K

R12
100
C9

0.047

R15
12K

180P

R16

3.3K

1K

R20

R21

1.5K

820

R22

C5

C10

R1
22

15K

C6

0.033

C7

0.1/50
C8

0.068

R19

1K

C3

1/50

C34

0.33/50

63 62

64

LDS

VCC1

–

+

FIN2

1

–

REF

+

FIN1

2

–

REF

+

E

3

F

4

REF

TB

5

R8

TE–

REF

6

TE

7

REF

TESI

8

SCI

9

REF

TH

10

NC

–

TD–

TD
JP
TO
FD

VREF

10

11

12

13

14

15

16

17

18

19

R56

22K

–

+

R18
15K

1

TO

2

FD

3

FO (GAIN)
FO+

4
5

FO–

6

TR+

7

TR–

8
9

GND

SL–
SL+
SLD
VCC1
STANDBY

20

Vref

21

MUTE

FD–

GEN

REF

17

R24
47K

+

REF

R17
33K

C11

0.1

C76

11
12

13
14
15
16

0.022

C33

0.47/50
C32

0.01

560

R46

61

LDO

RF

–

+

VCR

–

+

VCR

–

+

+

–

REF

+

REF

–

TO

+

–

GEN

REF

+

–

FA–

FA

18

19

10K

R23

IC3

M63001FP

FOCUS/TRACKING/SPIN

(SPN)VCC2

59

+

–

GND

SP+
SP–

SPO

–

+

+

–

FSC

REF

21

M–
M+

+

–

TGL1
THDL

FE–

22

58

LF2

REF

VCR

SERVO AMP.

GL
THD

FE1

REF

–

+

REF

SP

AGND

23

24

C16

0.0047

R27
39K

42
41
40
39
38
37
36
35
34

C82

33

100/16

32
31
30

C77

29

100/16

28
27
26
25
24
23
22

60

PHI

BHI

FE1
REF

VCR

JP

FOSTA

GEN

FE

20

C13

R26

330P

82K

C14

0.01
R25

1.5K

LD_M+
LD_M–

VCC4

SOL–
SOL+

/SLIDE DRIVER

VCC3

SOLD

SOL–

VR

LA9241M

VCC

REF

REF

SPI

C31

220/6.3

57

REF1

+

–

+

–

DEF

–

HFL

+

+

–

DRF

IC1

+

–
+

–

FSTA

S.Q.R

+

–

+

SPG

26

25

R28 10K

R31

1.2K

+B

C30

0.1/50

56

VCC2

REF

JP

–

SPO

SP–

27

C17

0.001

R30

6.8K

R29 56K

C18

0.47/50

55

FSS

54 53

EFBAL
FOSTA

TOSTA
2FREQ
LASER
FSTA
8/12CM
SLOF

+

–

+

–

JPCLO

REF

SLEO

28

C20

R33

1.2K

DRF

CV–REF
CV+
JP–

JP+

47/16

0.0033

52

CE

OR

REF

R32
10K

C21

LATOH

SLOF

SLOF

SLOF

SLD

C19

R34

1K

51

DAT

CE
CL

1/50

49

50

CL

FSC

REF

+

–

+

–

30

29

CLK

REF

RF

SL–

R35

DEF

DGND

RFS–

RFSM
CV+

CV–
SLOF

HFL
TES
TOFF
TGL

SL+

31

220K

+

–

JP+

NC

TBC

SLI

SLC

JP–

32

40

4

4
4

4
4 4

43

42

41

39
38
37
36
35
34
33

R36

8

7
6

5

C24

2.2P

R45

220K

R37
82K

4.7K

C27

0.001

R40

5.6K

HF

TP1

GND

C29

4.7/50

C26

0.033
R41

47K

C25
27P

R43
56K

R38
470

C28

0.1

C23

0.0027

C35

1/50

R44
33K

R42

47K

R39

1K

D1

1SS133

C22
220P

+B

+B

+B

R
1

+B

CNP12

RWC(DSP)

WRQ(DSP)

CO IN(DSP)

SQ OUT(DSP)

4 3 2 1

RES(DSP)

CQ CK(DSP)

6

5

H

• The numbers 1 to 12 are waveform numbers shown in page 14.

• NOTES ON SCHEMATIC DIAGRAM can be found on page 13.

1

23456

Figure 18 SCHEMATIC DIAGRAM (1/10)

– 18 –

P

FROM