SONY ICF403S - Service Manual Immediate Download

Ver 1.0 1999.08

MICROFILM

ICF-403S

SERVICE MANUAL

FM/MW/SW 3 BAND RADIO

SPECIFICATIONS

AEP Model

E Model

Australian Model

Saudi Arabia model

AEP, Australian model

Specifications ........................................................................... 1

1. GENERAL

Location and Function of Controls .................................... 2

2. DISASSEMBLY

2-1. Cabinet (Rear) ............................................................. 3

2-2. Cabinet (Front) ........................................................... 3

2-3. Main Board, Chassis ................................................... 4

3. DIAL POINTER INSTALLATION ........................... 5

4. ELECTRICAL ADJUSTMENTS ............................. 6

5. DIAGRAMS

5-1. Printed Wiring Boards ................................................ 7

5-2. Schematic Diagram ..................................................... 9

6. EXPLODED VIEWS ................................................... 11

7. ELECTRICAL PARTS LIST ................................... 13

Flexible Circuit Board Repairing

· Keep the temperature of the soldering iron around 270°C during

repairing.

· Do not touch the soldering iron on the same conductor of the

circuit board (within 3 times).

· Be careful not to apply force on the conductor when soldering or

unsoldering.

Notes on chip component replacement

· Never reuse a disconnected chip component.

· Notice that the minus side of a tantalum capacitor may be dam-

aged by heat.

TABLE OF CONTENTS

SECTION 1

GENERAL

Earphone jack (

DC IN 4.5V

LOCATION AND FUNCTION OF CONTROLS

SECTION 2

DISASSEMBLY

Note : Follow the disassembly procedure in the numerical order given.

2-1. CABINET (REAR)

2-2. CABINET (FRONT)

The equipment can be removed using the following procedure.

Cabinet (Front)

Cabinet (Rear)

Set

Main board, Chassis

1 Screw

+P 2.6x8

Cabinet (front)

Black ()

Brown

(+)

Chassis

Main board

2 Remove solder

Black ()

Brown (+)

1 Screws

+BTP 3x12

4 Screw

+P 2.6x8

Lug, 3

Cabinet (rear)

Cabinet (front)

2 Claws

1 Screws

+BTP 3x12

2-3. MAIN BOARD, CHASSIS

2 Claws

4 Knob(tune)

1 Screw

+P 2.6x8

Chassis

Main board

SECTION 3

DIAL POINTER INSTALLATION

Note : Follow the installation procedure in the numerical order given.

1 Rack

Rack

5 Knob (tone)

3 Knob (tune)

2 Pointer

Chassis

4 Scribed line

Claws

Main board

1 Insert the rack into the chassis groove.

2 Install the pointer.

3 Install the knob (tune).

4 Slide the rack and align it with the groove on the scribed

line.

5 Align the knob (tone) and the S2.

6 Install the chassis to the main board.

1 Turn the CV shaft all thye way counterclockwise.

2 Set the gear ASSY onto the CV shaft in a

direction as a figure.

3 Secure the gear ASSY with screw.

Gear (A),tuning capacitor

Stopper

Spring

(gear)

Hole

A Projection

Gear (B),tuning capacitor

B Hole

Spring (gear)

3 Screw (1.7x3)

2 Gear ASSY

CV shaft

Main board

Knob (tune)

1 Put a point of spring (gear) in a hole of "gear (A), tuning

capacitor" and install it.

2 Install "gear (B), tuning capacitor" in a direction as a figure.

3 Turn the "gear (B), tuning capacitor" till a position of B fits

4 Hang the spring (gear) with a stopper.

SECTION 4

ELECTRICAL ADJUSTMENTS

TUNER SECTION

MW Section

Procedure :

BAND : MW

SW Section

Procedure :

BAND : SW

FM Section

Procedure :

BAND : FM

AM RF signal

generator

30% amplitude modulation by 400Hz

signal.

Output level : as low as possible

Put the lead-wire

antenna close to

the set.

Repeat the procedures in each adjustment several times, and the

frequency coverage and tracking adjustments should be finally

done by the trimmer capacitors.

> : Saudi Arabia model

AM IF ADJUSTMENT