SONY WMPA1 - Service Manual Immediate Download

Model Name Using Similar Machanism

WM-FX123

Tape Transport Mechanism Type

MF-WMFX103-48CY

MICROFILM

WM-PA1

SERVICE MANUAL

RADIO CASSETTE PLAYER

SPECIFICATIONS

E Model

Radio Section

:87.6 108MHz

AM :530 1,710kHz

Power Requirements

3V DC Batteries AA (R6) x 2

External DC 3V power sources

Battery Life

(approximate hours when using the batteries specified below)

Battery

Playback

Radio

Sony Alkaline LR6 (SG)

16 hours

48 hours

Sony R6P (SR)

4.5 hours

16 hours

Dimensions

94.2x 119.0 x 36.0 mm

Mass

260g incl. batteries and tape

Supplied Accessories

· Stereo headphones (1)

· Belt clip (1)

Design and specifications are subject to change without notice.

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

1. GENERAL

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

2. DISASSEMBLY

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

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

2-3. Main Board, Mechanism Deck Removal ................... 4

2-4. Cassette Holder Sub Assy Removal ........................... 4

2-5. Switch board Removal ............................................... 5

2-6. Dial Pointer Setting .................................................... 5

3. ADJUSTMENTS

3-1. Mechanical Adjustment .............................................. 6

3-2. Electrical Adjustment ................................................. 6

4. DIAGRAMS

4-1. Block Diagram ............................................................ 8

4-2. Printed Wiring Boards .............................................. 10

4-3. Schematic Diagram ................................................... 15

5. EXPLODED VIEWS

5-1. Cabinet and Board Section ....................................... 19

5-2. Mechanism Deck Section ......................................... 20

6. ELECTRICAL PARTS LIST ................................ 21

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

LOCATION AND FUNCTION OF CONTROLS

· HOW TO CHANGED THE CERAMIC FILTERS

This model is used two ceramic filters of CF2 and X2.

You must used same type of color marked ceramic filters in order

to meet same specifications.

Therefore, the ceramic filter must changed two pieces together

since it's supply two pieces in one package as a spare parts

mark

CF2

Mark

Center Frequency

red

10.70MHz

blue

10.67MHz

orange

10.73MHz

black

10.64MHz

white

10.76MHz

··

NORM LIMIT

AVLS

··

NORM CrO2/

METAL

DX LOCAL

APE

(RADIO

OFF)

PLAY

SPEAKER

SWITCH

DC IN 3V

VOLUME

TUNING

0 )

SECTION 2

DISASSEMBLY

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

2-1. CABINET (REAR) REMOVAL

2-2. CABINET (FRONT) REMOVAL

The equipment can be removed using the following procedure.

Main board, Mechanism deck

Cabinet (Front)

Cabinet (Rear)

Cassette holder sub assy

Switch board

Set

Cassette holder sub assy

Cabinet (Rear)

Cabinet (Front)

1 Flexible board

2-3. MAIN BOARD, MECHANISM DECK REMOVAL

2-4. CASSETTE HOLDER SUB ASSY REMOVAL

Main board

Mechanism deck

1 Remove solder

2 Head flexible board

3 Claw

3 Claws

Cabinet (Front)

3 Flexible board

Cassette holder sub assy

1 Attach the torsion spring

as shown in the figure

2 Insert the torsion spring

in the hole as shown in the figure.

3 Lift the torsion spring in the arrow

direction and hook it properly

NOTE FOR INSTALLATION

The torsion spring will be removed together with the cassette lid that preform the following for installation.

TORSION SPRING

1 Screws

(1.7x3) tapping

Retainer, Speaker

Speaker

Cassette holder sub assy

Switch board

2-5. SWITCH BOARD REMOVAL

2-6. DIAL POINTER SETTING

2 Align pointer with arrow marked

side as shown in Fig. 1 and then

fit to groove in the order of a and b.

1 Rotate tune knob fully to arrow direction.

Align point

Ferrite-rod antenna sub assy

(A=B)

Align point

Pointer

Fig. 1

Pointer

Ferrite-rod antenna sub assy

Knob (tune)

Main board

TUNER SECTION

AM Section

BAND : AM

FM Section

BAND : FM

LOCAL/DX switch : DX

· Repeat the procedures in each adjustment several times, and the

frequency coverage and tracking adjustments should be finally

done by the trimmer capacitors.

Adjustment Location :

[MAIN BOARD] (Side A)

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

(ANT TAP)

(GND)

0.01 F

set

J302 (phones)

level meter

AM IF ALIGNMENT