SHARP QT-CD180BL, QT-CD180RD, QT-CD180S, QT-CD180WH Service Manual

QT-CD180

SERVICE MANUAL

No. S1102QTCD180/

PORTABLE CD STEREO SYSTEM

MODEL

QT-CD180(BL) QT-CD180(RD) QT-CD180(S) QT-CD180(WH)

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

CONTENTS

Page

IMPORTANT SERVICE NOTES (FOR U.S.A. ONLY)....................................................................................................... 2

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

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

FITTING OF DIAL POINTER ............................................................................................................................................. 3

OPERATION MANUAL ...................................................................................................................................................... 4

DISASSEMBLY.................................................................................................................................................................. 5

REMOVING AND REINSTALLING THE MAIN PARTS..................................................................................................... 6

ADJUSTMENT ................................................................................................................................................................... 8

NOTES ON SCHEMATIC DIAGRAM .............................................................................................................................. 11

TYPES OF TRANSISTOR ............................................................................................................................................... 11

SCHEMATIC DIAGRAM .................................................................................................................................................. 12

WIRING SIDE OF P.W.BOARD....................................................................................................................................... 14

WAVEFORMS OF CD CIRCUIT...................................................................................................................................... 16

TROUBLESHOOTING (CD SECTION) ........................................................................................................................... 17

FUNCTION TABLE OF IC................................................................................................................................................ 21

PARTS GUIDE/EXPLODED VIEW PACKING OF THE SET (FOR U.S.A. ONLY)

SHARP CORPORATION

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

QT-CD180

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

0.15µF

TEST PROBE

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.

CONNECT TO KNOWN EARTH GROUND

■

General

Power source

Power consumption Output power

Speakers Dimensions

Weight

■

Compact disc player

Type Signal readout Audio channels Filter D/A converter Wow and flutter

■

Radio

Frequency range

■

Tape recorder

Frequency response Signal/noise ratio Wow and fiutter Motor Bias system Erase system

AC 120 V, 60 Hz

DC 9 V [“D” size (UM/SUM-1, R20 or HP-2) battery x 6] 11 W FTC; 2.0 W min. RMS per channel into 4 ohms from 150

Hz to 20 kHz, with no more than 10 % total harmonic distortion. RMS; 2.3 W/CH (DC operation, 10 % T.H.D)

3-1/8" (8 cm) full-range speaker x 2

Width; 14-6/8" (376 mm) Height; 5-7/8" (150 mm) Depth; 9" (230 mm)

5.5 lbs. (2.5 kg) without batteries

Compact disc

Non-contact, 3-beam semi-conductor laser pickup

8-time oversampling digital filter

1-bit D/A converter

Unmeasurable (less than 0.001% W. peak)

FM; 87.5 - 108 MHz AM; 530 - 1,720 kHz

50 - 14,000 Hz (Normal tape)

50 dB

0.25 % (WRMS)

DC 9 V electric governor

AC bias

Magnet erase

SPECIFICATIONS

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

– 2 –

1234567

QT-CD180

NAMES OF P ARTS

8 9 10 11 12

14 15

01. Volume Control

02. Function Switch

03. CD Compartment

04. (TAPE) Pause Button

05. (TAPE) Stop/Eject Button

06. (TAPE) Fast Forward Button

07. (TAPE) Rewind Button

08. Tuning Control

09. (TAPE) Play Button

10. (TAPE) Record Button

11. (CD) Play/Pause Button

12. (CD) Track Up/Cue Button

13. Cassette Compartment

14. (CD) Stop Button

15. (CD) Track Down/Review Button

16. (CD) Play Indicator

17. (CD) Pause Indicator

FITTING OF DIAL POINTER

Setting method of the dial pointer

1. Remove the front cabinet. (Refer to Fig.5-2 on page 5, "Disassembly method".)

2. Remove the dial pointer.

3. Insert the dial pointer from A of the top cabinet so that it engages with the drum gear.

4. Fully turn the drum in the opposite direction of B and set it to the FL marks.

5. Reassemble the front cabinet.

18. Battery Compartment

19. FM Telescopic Rod Antenna

20. AC Power input Socket

Dial Pointer

Top Cabinet

Variable Capacitor

Drum

Tuning Knob

Main PWB

Dial Pointer

Main PWB

Drum

Tuning Knob

Figure 3-1

– 3 –

Variable Capacitor

Top Cabinet

FL Mark

Main PWB

Drum

Dial Pointer

Tuning Knob

Dial Pointer

QT-CD180

OPERATION MANUAL

Quick Guide /

Preparation for use /

■ Operation with AC power

Funccionamiento con corriente alterna

■

T o AC INPUT

A la toma AC INPUT

AC 120 V, 60 Hz

120 V de CA, 60 Hz

To an AC outlet

A un tomacorriente de CA

Listening to a CD /

Guía rápida

Preparación para su uso

■ Operation with batteries

Funccionamiento con pilas

■

● 6 “D” size batteries (UM/SUM-1, R20, HP-2 or similar)

● Batteries are not included.

●

6 pilas del tamaño “D” (UM/SUM-1, R20, HP-2 o similares)

●

Las pians no están incluidas.

Audictión de CD

■ Turning the power

ON and OFF

Conexión (ON) y

■

desconexión (OFF) de la alimentación

123 45

● Label side up.

●

Con el lado de la etiqueta

encarada hacia arriba.

Listening to a tape /

Audictión de una cinta

123

To stop playback

Press the STOP/EJECT ■ button.

Para detener la reproducción

Pulse el botón STOP/EJECT

Recording from a CD /

Grabaciones de CD

■

To stop playback

Press the STOP ■ button.

Para detener la reproducción

Pulse el botón STOP

Listening to the radio /

Audic

tión de la radio

■

● Load the disc to be recorded.

Introduzca el disco que

●

va a grabar.

– 4 –

To stop recording

Press the STOP/EJECT ■ button.

Para detener la grabación

Pulse el botón STOP/EJECT

■

DISASSEMBLY

(C3)x5 ø3x10mm

(D1)x2 ø3x8mm

(C4)x1 ø2.5x10mm

(C5)x1

(C2)x3

(C1)x1

Volume PWB

Tape Mechanism

CD Mechanism

CD Motor

PWB

Main PWB

Top Cabinet

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.

STEP REMOVAL PROCEDURE FIGURE

1 Rear Cabinet 1. Screw ................... (A1) x4 5-1

2. Socket .................. (A2) x1

2 Front Cabinet 1. Open the cassette holder 5-2

2. Socket .................. (B1) x1

3. Screw ................... (B2) x4

4. Screw ................... (B3) x2

3 Main PWB 1. Knob..................... (C1) x1 5-3

(With CD Control 2. Socket .................. (C2) x3

PWB) 3. Screw ................... (C3) x5

(Note) 4. Screw ................... (C4) x1

5. Socket .................. (C5) x1

4 Tape Mechanism 1. Screw ................... (D1) x2 5-3

5 CD Control PWB 1. Screw ................... (E1) x2 5-4

(With Main PWB) 2. Bracket................. (E2) x2

6 CD Mechanism 1. Screw ................... (F1) x3 5-4

7 Power PWB 1. Battery Lid............(G1) x1 5-5

2. Screw ................... (G2) x1

3. Bracket ................. (G3) x1

4. Hook..................... (G4) x1

Note:

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

Main PWB

(B2)x4 ø3x10mm

(E2)x1

(B3)x1 ø3x8mm

(E2)x1

(B1)x1

Figure 5-2

Figure 5-3

(E1)x2 ø3x10mm

QT-CD180

Open

Cassette

Holder

Tape Mechanism

(B3)x1 ø3x8mm

Front Cabinet

(F1)x3 ø2.5x10mm

PWB Washer x3

CD Mechanism

Top Cabinet

(A1)x4 ø3x14mm

Figure 5-1

Main PWB

(A2)x1

Front Cabinet

Rear Cabinet

CD Control PWB

Figure 5-4

(G2)x1 ø3x10mm

(G3)x1

(G4)x1

Power PWB

Driver

(G1)x1

Rear Cabinet

Figure 5-5

– 5 –

QT-CD180

REMOVING AND REINSTALLING THE MAIN PARTS

TAPE MECHANISM SECTION

Perform steps 1 to 4 of the disassembly method to remove the tape mechanism. (See page 5.)

How to remove the record / playback and erase heads (See Fig. 6-1.)

1. Remove the screws (A1) x 2 pcs., to remove the record/ playback head.

2. Remove the hooks (A2) x 2 pcs., toward the center position as shown in Fig. 6-1. and then extract the erase head upward.

Note:

After replacing the heads and performing the azimuth adjustment, be sure to apply screwlock.

How to remove the pinch roller (See Fig. 6-2.)

1. Remove the screw (B1) x 1 pc., and remove the pinch roller upwards.

Hook (A2)x2

Erase Head

Pinch Roller

(A1) x1 ø2x7mm

Figure 6-1

Figure 6-2

(A1) x1 ø2x3mm

(B1) x1 ø1.5x2.5mm

Record/Playback Head

How to remove the belts (See Fig. 6-3.)

1. Remove the main belt (C1) x 1 pc., from the motor

pulley.

2. Remove the FF/REW belt (C2) x 1 pc., from the REW/FF

roller.

3. Put on the belts in the reverse order of removal.

Note:

When putting on the belt, ascertain that the belt is not twisted, and clean it.

How to remove the motor (See Fig. 6-4.)

1. Remove the main belt. (See Fig. 6-3.)

2. Remove the screws (D1) x 2 pcs., to remove the motor

bracket.

3. Remove the screws (D2) x 2 pcs., to remove the motor.

Note:

When mounting the motor, pay attention to the motor bracket angle.

Main Belt (C1)x1

Flywheel

FF/REW Belt (C2)x1

Motor

Motor Pulley

REW/FF Roller

Figure 6-3

(D2)x2 Special Screw

Motor Bracket

– 6 –

(D1) x1 ø2.5x4mm

Motor

Figure 6-4

QT-CD180

How to remove the flywheel (See Fig. 7-1.)

1. Remove the belt. (See Fig. 6-3.)

2. Remove the stop washer (E1) x 1 pc., with a small precision screwdriver to extract the flywheel from the capstan metal.

Note:

When the stop washer is deformed or damaged, replace it with a new one.

How to reinstall the parts

Install each part in the reverse order of the removal with care.

CD MECHANISM SECTION

Perform steps 1 to 6 of the disassembly method to remove the CD mechanism. (See page 5.)

How to remove the pickup (See Fig. 7-2.)

1. Remove the screws (A1) x 2 pcs., to remove the shaft (A2) x1 pc.

2. Remove the stop washer (A3) x1 pc., to remove the gear (A4) x 1 pc.

3. Remove the pickup.

(E1) x 1 Stop Washer

Washer

Flywheel

(A1) x2

ø2.6 x6mm

Pickup

Figure 7-1

CD Mechanism

Note:

Shaft (A2) x1

Figure 7-2

Gear (A4) x1

Stop Washer (A3) x1

– 7 –

QT-CD180

ADJUSTMENT

MECHANISM SECTION

• Driving Force Check

Torque Meter

PLAY: TW-2412 Over 80 g

• Torque Check

Torque Meter

Play: TW-2111 30 to 60 g.cm Fast Forward: TW-2231 55 to 140 g.cm Rewind: TW-2231 55 to 140 g.cm

• Head Azimuth

Torque Meter

MTT-114 Output: Speaker Terminal

(CNP201 Load resistance: 4 ohms)

• Tape Speed

Test

Tape

Adjusting

Point

MTT-111 Variable 3,000 ± 90 Hz Output: Speaker

resistor in Terminal motor. (M601) (CNP201 Load

Specified

Specified Value

Value

Instrument

Connection

resistance: 4 ohms)

TUNER SECTION

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

• FM IF/RF

Test Stage

Specified

Value/Adjusting

Point

FM Detection T2

FM fL: L2 Band Coverage fH: TC2

FM Tracking fL: 88.0 MHz: L1

fH: 108.0 MHz: TC1

• AM IF/RF

Test Stage

AM IF T3 Input: Antenna

AM fL: L4 Input: Antenna Band Coverage fH: TC4 Output: Speaker AM Tracking fL: 600 kHz: L3 Terminal (CNP201

Specified

Value/Adjusting

Point

fH: 1,400 kHz: TC3 Load resistance: 4

Instrument

Connection

Input: Pin 1 of IC1 Output: Pin 18 of IC1

Input: Antenna Output: Speaker Terminal (CNP201 Load resistance: 4 ohms)

Instrument

Connection

Output: Pin 18 of IC1

ohms)

TAPE SECTION

Position of each switch or control

Volume control Max Function switch Tape/Power Off

• Bias Oscillation

L301

IC101

Instrument

Connection

Adjustment Point

Specified Value

L301 80 kHz ± 6 kHz Pin 1 of CNP101

FM ROD ANTENNA

AM BAR

ANTENNA

TC1

DETECTION

IC1

fL fH

AM IF

FM BAND COVERAGE

BIAS OSC.

AM BAND COVERAGE

TC3

TC4

TC2

fL AM TRACKING

fH FM TRACKING

MAIN PWB

IC803

BI803

4 3 2 1

SW102

CNP101

• Playback Amplifier Sensitivity Check

Test Tape

Specified Value

MTT-118 1.1 V ± 3 dB Speaker Terminal

TAPE MOTOR

IC802

BI802

IC801

BI801

Instrument Connection

(Load resistance: 4 ohms)

M601

TAPE MECHANISM

SW601 TAPE MAIN

CNP602

SW201

Variable resistor in motor

CNP201

IC201

VR201

Figure 8 ADJUSTMENT POINTS

– 8 –

QT-CD180

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.

TEST MODE

Start Note

While holding down the "Stop" and "Up" button at same time, move the FUNCTION switch to "CD".

1. When the CD LID switch is in the OFF position, (CD LID is open) the unit will be able to enter the test mode. However, can use the "UP/CUE" and "DOWN/REVIEW" button only.

2. You can only move the pickup.

3. The LCD display should be the same as it is for normal CD operations.

Operation

The use of the "UP/CUE" button will move the pickup to the outermost position. The use of the "DOWN/REVIEW" button will move the pickup to the innermost position.

LCD MODE

Start

Display

After connecting of the 10 kohm resistor between IC802 27 pin and GND and holding down the "Stop" and "Up" button at same time, move the FUNCTION switch to "CD".

LASER LIGHTING CONFIRMATION

1. Remove the front cabinet according to the disassembly method.

2. Short the TP of the Figure 9-1 to turn on the CD LID switch (SW810).

3. While holding down the "Stop" and "Up" button at same time, move the FUNCTION switch to "CD".

4. Open the CD LID and press the PLAY button. The laser lights up for a few seconds. (At this time, the pickup lens moves up and down and adjusts the focus to check if there is a disc or not.)

PREPARATION FOR LASER LIGHT UP

1. Before the laser light up, CD LID switch (SW801) terminals have to be short with the solder. Resistor of 330ohm is put from 27 pin of IC802, and you must connect it to GND of PWB. (Refer to PWB of Figure9-1.)

MAIN PWB-A1

OPEN/CLOSE

SW810 CD LID

SWITCH

330 ohm Resistor

PLAY

C847

C846

R862

FW806

REC.

C844 C853

C855

100

R839

R844

GND

CNP101

SW102

R846

C824

27pin

R861

1234

X801

IC802

R843

R821

SW102 RECORD/PLAYBACK

C84

C843

C825

C106

Figure 9-1

R830 R829

C833

C823

R106

R826

R824

C863

R828

C828

C830

C841

R827

C827

C826

C842

BI803

GYGYGY

R820

C819

C829

R804

C839

R851

R805

C817

C820

R806

C815

C838

C835

R852

Q801

R801

C816

C804

C801

C802

C834

IC803

IC801

R853

805

BI802

R802

BI801

C807

– 9 –

QT-CD180

SETTING METHOD FOR LASER LIGHT UP

1. In Power OFF state, set the Function switch to ON, keeping to be pressed the "Stop" and "Up" button at same time.

After CD initialize finish. The CD TEST mode is set, and the LCD indicate to the total tracks of the disc. Release the PLAY button.

The CD TEST mode is set when the LCD indicate to " 1". Then cut the above circuit.

2. In above TEST mode state, press once the PLAY button.

The laser is light up when LCD indicate to "cd".

SETTING FOR MAXIMUM LASER POWER

1. In above laser light up state, adjust the variable resistor (VR1A) on pickup PWB to maximum laser power. Maximum laser power : Rotate the variable resistor (VR1A) to clockwise.

PICKUP UNIT

Pickup PWB

Note : The TEST mode is cleared by Power OFF.

Variable Resistor VR1A

Figure 10

– 10 –

+ 22 hidden pages