Sharp QT-222-W Service manual

QT-222W

SERVICE MANUAL

No. SX376QT222W//

RADIO CASSETTE RECORDER

MODEL

QT-222W(S)

RADIO CASSETTE RECORDER

QT-222W(BK)

• 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

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

VOLTAGE SELECTION..................................................................................................................................................... 2

AC POWER SUPPLY CORD AND AC PLUG ADAPTOR ................................................................................................. 2

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

HOW TO SET THE POINT "0" ON TUNER DIAL MEMORY............................................................................................. 3

DISASSEMBLY.................................................................................................................................................................. 4

REMOVING AND REINSTALLING THE MAIN PARTS..................................................................................................... 5

ADJUSTMENT ................................................................................................................................................................... 6

NOTES ON SCHEMATIC DIAGRAM ................................................................................................................................ 9

TYPES OF TRANSISTOR ................................................................................................................................................. 9

VOLTAGE .......................................................................................................................................................................... 9

SCHEMATIC DIAGRAM .................................................................................................................................................. 10

WIRING SIDE OF P.W.BOARD....................................................................................................................................... 12

PARTS GUIDE/EXPLODED VIEW

This document has been published to be used

SHARP CORPORATION

– 1 –

for after sales service only. The contents are subject to change without notice.

QT-222W

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

General

Power source

Power consumption Output power

Speaker Output terminal Dimensions

Weight

Radio

Frequency range

SPECIFICATIONS

AC 110-127/220-240 V, 50/60 Hz DC 6 V [“D” size (UM/SUM-1, R20 or HP-2) battery x 4]

7 W MPO: 3 W (AC operation, 10 % T.H.D.)

RMS: 1.5 W (DC operation, 10 % T.H.D.)

9.2 cm (3-5/8”) full range speaker x 1 Earphone: 16-50 ohms (recommended: 32 ohms) Width: 305 mm (12”)

Height: 155 mm (6-1/8”) Depth: 120 mm (4-3/4”)

1.48 kg (3.3 lbs.) without batteries

FM: 88 - 108 MHz SW1: 2.3 - 7.3 MHz SW2: 7.3 - 22 MHz MW: 526.5 - 1,606.5 kHz

Tape recorder

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

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

Before operating the unit on mains, check the preset voltage. If the voltage is different from your local voltage, adjust the voltage as follows. Slide the selector with a screwdriver to the appropriate voltage number. (AC 110 - 127 V or AC 220 - 240 V)

AC POWER SUPPLY CORD AND AC PLUG ADAPTOR

92L24801600292

60 - 12,000 Hz (Normal tape) 40 dB

0.3 % (WRMS) DC 6 V electric governor DC bias Magnet erase

VOLTAGE SELECTION

92L26802125210

92L26802125120

92L24801800222

– 2 –

NAMES OF P ARTS

1. Earphone Socket

2. Built-in Microphone

3. Function Switch

4. Band Selector

5. Fine Tuning Control

6. Volume Control

7. Tuning Control

8. Pause Button

9. Stop/Eject Button

10. Cassette Compartment

11. Fast Forward Button

12. Rewind Button

13. Play Button

14. Record Button

15. Battery Compartment

16. AC Input Socket

17. AC Voltage Selector

18. FM/SW Telescopic Rod Aerial

QT-222W

23 45 6 7

8 9 10 11 12 13 14

"0" Point

Dial Pointer(219)

Screw(612) ø3x12mm

15 16 17 18

HOW TO SET THE POINT "0" ON TUNER DIAL MEMORY

1) Firstly, remove the front cabinet.

2) Remove 2 screw from tuning bracket.

3) rotate tuning knob until end of right side (same as arrow direction A ).

4) Attach the dial pointer slot inside the tuning bracket properly as shown by arrow.

5) Ensure the dial pointer's step must touch the pointer cover this point to adjust and set the dial pointer for tuning adjustment purpose.

6) Fitting the tuning bracket (after assembled with dial pointer) to the tuning knob.

Tape Mechanism

Tuning Bracket (214)

Front Cabinet

Tuning Knob (230)

Main PWB

Figure 3

– 3 –

QT-222W

(D1)x2 ø3x10mm

(C4)x1

(C1)x1

(C3)x1

(C2)x7 ø3x10mm

Power PWB

Main PWB

Front Cabinet

(B2)x1

(B5)x1

(A2)x1

(B5)x1

(B3)x1

(B1)x2 ø3x8mm

(B4)x2 ø3x8mm

Tape Mechanism

Front Cabinet

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 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) x5 4-1

2. Socket .................. (A2) x1 4-2

2 Tape Mechanism 1. Screw ................... (B1) x2 4-2

2. Tuning Bracket..... (B2) x1

3. Tuning Knob......... (B3) x1

4. Screw ................... (B4) x2

5. Socket .................. (B5) x2

3 Main PWB 1. Knob .....................(C1) x2 4-3

2. Screw ................... (C2) x7

3. Tip ........................ (C3) x1

4. Socket .................. (C4) x1

4 Power PWB 1. Screw ................... (D1) x2 4-3

Figure 4-2

Figure 4-1

Front Cabinet

(A1)x5 ø3x25mm

Rear Cabinet

Figure 4-3

– 4 –

REMOVING AND REINSTALLING THE MAIN PARTS

TAPE MECHANISM SECTION

Perform steps 1 to 2 of the disassembly method to remove the tape mechanism. (See page 4.)

How to remove the record / playback and erase heads (See Fig. 5-1.)

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. 5-1. 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 belts (See Fig. 5-2.)

1. Remove the main belt (B1) x 1 pc., from the motor pulley.

2. Remove the FF/REW belt (B2) 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.

Push

Flywheel

Hook (A2)x2

PLAY Button

Erase Head

Main Belt (B1)x1

QT-222W

(A1)x2 ø2x7mm

Lug Wire

Record/Playback Head

Figure 5-1

Motor

Motor Pulley

How to remove the motor (See Fig. 5-3.)

1. Remove the main belt. (See Fig. 5-2.)

2. Remove the screws (C1) x 1 pc., to remove the motor bracket.

3. Remove the screws (C2) x 2 pcs., to remove the motor.

Note:

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

FF/REW Belt (B2)x1

(C1)x1 ø2x4mm

(C2)x2 ø2.6x1.6mm Special Screw

REW/FF Roller

Figure 5-2

Motor

Motor Bracket

– 5 –

Motor

Figure 5-3

+ 10 hidden pages

Sharp QT-222-W Service manual

Specifications and Main Features

Frequently Asked Questions

User Manual