SONY ICF403L - Service Manual Immediate Download

Ver 1.0 1999.07

MICROFILM

ICF-403L

SERVICE MANUAL

FM/MW/LW 3 BAND RADIO

SPECIFICATIONS

AEP Model

East European model

AEP 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

3 Screw (1.7x3)

2 Gear (A),tuning capacitor

CV shaft

Main board

Knob (tune)

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 (A), tuning capacitor onto the CV shaft in a

direction as a figure.

3 Secure the gear (A), tuning capacitor with screw.

SECTION 4

ELECTRICAL ADJUSTMENTS

TUNER SECTION

MW/LW Section

Procedure :

BAND

: MW/LW

VOLUME : MIN

FM Section

Procedure :

BAND

: FM

VOLUME : MIN

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.

FM RF signal

generator

22.5kHz frequency deviation by

400Hz signal.

Output level : as low as possible

telescopic

antenna

terminal

0.01

µF

set

phone jack (J1)

level meter

Repeat the procedures in each adjustment several times, and the

frequency coverage and tracking adjustments should be finally

done by the trimmer capacitors.

> : East European model

AM IF ADJUSTMENT