Sony WMFS-555 Service manual

WM-FS555/FS555J/FS556

SERVICE MANUAL

Ver 1.3 2003.06

Photo : WM-FS555

Model Name Using Similar Mechanism NEW

MD Mechanism Type MF-WMFS555-114

SPECIFICATIONS

US Model

WM-FS555/FS555J/FS556

Canadian Model

WM-FS555/FS555J

AEP Model

E Model

WM-FS555

• Frequency

TV: 2-13 ch WEATHER: 1-7ch FM: 87.5-108 MHz AM: 530-1710 kHz (North, Central and South America)

531-1602 kHz (Other counries)

•Power requirements

1.5 V DC battery size AA (R6) × 1

• Dimensions

Approx. 102.3 × 117.5 × 47.3 mm (4 1/8 × 4 3/4 × 1 7/8 inches) including projecting parts and controls

• Mass

Approx. 219 g (7.8 oz) (main unit only)

• Supplied accessories

Stereo headphones or earphones (1) Hand strap with belt clip (1)

Design and specifications are subject to change witout notice.

9-873-595-04

2003F02-1

RADIO CASSETTE PLAYER

Sony Corporation

Personal Audio Company

Pubulished by Sony Engineering Corporation

WM-FS555/FS555J/FS556

TABLE OF CONTENTS

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

1. GENERAL ...................................................................... 2

2. DISASSEMBLY

2-1. Chassis, H/P Board ..................................................... 3

2-2. Main Board ................................................................. 3

2-3. Mechanism Deck ........................................................ 4

2-4. Belt, Capstan/reel Motor (M601),

Magnetic Head (Playback) (HP601) ........................... 4

3. ADJUSTMENTS

3-1. Mechanical Adjustments ............................................ 5

3-2. Electrical Adjustments ................................................ 5

4. DIAGRAMS

4-1. Explanation of IC Terminals ....................................... 8

4-2. Block Diagrams .......................................................... 9

4-3. Printed Wiring Boards – Main Section – .................. 10

4-4. Schematic Diagram – Main Section (1/2)– ............... 11

4-5. Schematic Diagram – Main Section (2/2)– .............. 12

4-6. IC Block Diagrams ................................................... 13

5. EXPLODED VIEWS

5-1. Cassette Lid Section ................................................. 15

5-2. Cabinet Section ......................................................... 16

5-3. Mechanism Deck Section

(MF-WMFS555-114) ............................ 17

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 damaged by heat.

6. ELECTRICAL PARTS LIST ................................... 18

SECTION 1

GENERAL

Rubber cap

Air outlet

SET

ENTER

This section is extracted from instruction manual.

HOLD

TV/WEATHER (US), FM (EXCEPT US)

FM/AM (US), AM (EXCEPT US)

n**

TUNING+/–

PRESET +/–

RADIO OFF

VOLUME*

* There is a tactile dot beside VOLUME on the main unit to

show the direction to turn up the volume.

The button has a tactile dot.

SECTION 2

DISASSEMBLY

The equipment can be removed using the following procedure.

Set

Main boardChassis, H/P board

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

2-1. CHASSIS, H/P BOARD

Chassis

Mechanism deck Belt, Capstan/reel motor (M601),

2 Two screws (B1.7 × 8)

WM-FS555/FS555J/FS556

Magnetic head (playback) (HP901)

H/P board

2-2. MAIN BOARD

3 Claws

1 Remove solder

(four places)

1 Open the “lid, Cassette”

Cabinet (rear) sub ASSY

4 Claws

Chassis

3 Screw (WH M1.4)

Head flexible board

Main boar

2 Remove solder (six places)

WM-FS555/FS555J/FS556

2-3. MECHANISM DECK

Chassis

1 Claw

Mechanism deck

2-4. BELT, CAPSTAN/REEL MOTOR (M601), MAGNETIC HEAD (PLAYBACK) (HP901)

Two screws (M1.4)

Capstan/reel motor

(M601)

magnetic head (PLAYBACK) (HP901)

Mechanism deck

Belt

• How to apply the belt

Belt

wheel ASSY (P), capstan

Capstan/reel motor (M601)

SECTION 3

set

test tape WS-48A (3kHz, 0dB)

frequency counter

16 Ω

phones jack (J301)

RV601: Tape speed Adjustment

ADJUSTMENTS

WM-FS555/FS555J/FS556

3-1. MECHANICAL ADJUSTMENTS

PRECAUTION

1. Clean the following parts with a denatured-alcohol-moistened swab :

playback head pinch roller capstan rubber belt

2. Demagnetize the playback head with a head demagnetizer. Do not use a magnetized screwdriver for the adjustments.

3. These measurement and adjustment should be performed with the rated power supply voltage (1.5 V) unless otherwise noted.

Torque Measurement

Mode Torque meter Meter reading

FWD

CQ-102C

FWD

back tension

REV 20 – 42 g • cm

CQ-102RC

REV

back tension

FF, REW CQ-201B

1.97 – 4.11 mN • m 20 – 42 g • cm

(0.28 – 0.58 oz• inch)

less than 0.19 mN • m

less than 2 g • cm

(less than 0.027 oz• inch)

1.97 – 4.11 mN • m

(0.28 – 0.58 oz• inch)

less than 0.19 mN • m

less than 2 g • cm

(less than 0.027 oz• inch)

more than 3.93 mN • m

more than 40 g • cm

(more than 0.56 oz• inch)

3-2. ELECTRICAL ADJUSTMENTS

PRECAUTION

• Supplied voltage : 1.5 V.

• Switch and control position (MENU display) MEGA BASS : OFF VOLUME control (RV301) : maximum AVLS : OFF (No indicated) FM MODE : US : DX (No indicated)

Canadian, AEP, E : STEREO (No indicated)

TAPE SECTION

Test Tape

Type Signal Used for

WS-48A 3kHz, 0dB Tape Speed Adjustment

Tape Speed Adjustment

Procedure :

0 dB = 0.775V

1. Playback WS-48A (tape center part) in the FWD state and adjust RV601 so that the frequency counter reading becomes 3,000Hz. Standard value : 2,985–3,015Hz

2. Playback WS-48A (tape center part) in the REV state. Check that frequency counter reading is within ±1.0% of the reading of step 1.

Adjustment Location :

WM-FS555/FS555J/FS556

OFF

C15

TAP102

C22

Q305

TUNER SECTION

AM Section

BAND : AM

AM RF signal generator

30% amplitude modulation by 400Hz signal. Output level : as low as possible

FM Section

BAND : FM

US model only

TV/WEATHER Section

BAND: TV/WEATHER

TP(RF)

FB301

MAIN BOARD (SIDE B)

JC4

FB1

TAP105

C34

R10

0 dB = 1µV

(RF)

C26

C35

Put the lead-wire antenna close to the set.

FM RF signal generator

0.01

33.75kHz frequency deviation by 1kHz signal. Output level : as low as possible

C207

C107

TAP103

AM TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L4 620kHz <621kHz>

CT1 1,400kHz <1,395kHz>

FM FREQUENCY COVERAGE CONFIRMATION

Frequency display Reading on digtal voltmeter

Confirmation 87.5MHz Standard value : 6.5V or less

Confirmation 108MHz 8.9 ± 0.4V

FM TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L2 87.5MHz (US), 98MHz (EXCEPT US)

Confirmation 108MHz

US model only

TV FREQUENCY COVERAGE CONFIRMATION

Frequency display Reading on digtal voltmeter

Confirmation TV 2CH 1.1 ± 0.15V

Confirmation TV 13CH 8.0 ± 0.4V

Confirmation WEATHER 1CH 3.65 ± 0.3V

TV TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L7 TV 7CH

C23

TAP106

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

C37

16 Ω

set

phones jack (J301)

FERRITE–ROD

TP304

level meter

frequency coverage and tracking adjustments should be finally done by the trimmer capacitors.

AM FREQUENCY COVERAGE ADJUSTMENT

Adjust parts Frequency display

Confirmation

530kHz 1.1 ± 0.15 V

<531kHz>

1,710kHz 8.6 ± 0.4 V

<1,602kHz> 9.5 ± 0.4 V

no mark : 10kHz step < > : 9kHz step

Reading on digtal

voltmeter

ANTENNA

1-6

Adjustment Location : Main board (See page 7)

Frequency Coverage Adjustment

Setting :

MAIN BOARD (SIDE B)

C11

C12

C21

JC1

R13

C20

C26

R10

C35

C28

C19

C13

Q302

C14

C331

R213

FERRITE–ROD

ANTENNA

TP304

R21

R20

R113

C107

TAP103

TP (VT)

R208

Q305

C207

digital voltmeter

R207

C24

C23

C22

1-682-795-

(DC range)

R716

Q703

R107 R108 R105 R205

C30

C29

C31

(VT)

TAP104

(11)

Adjustment Location :

WM-FS555/FS555J/FS556

[MAIN BOARD] 

(SIDE A)

CT1 : AM Tracking Adjustment

L5 : AM Frequency Coverage Adjustment

L2 : FM Tracking Adjustmen

L7 : TV Tracking Adjustment

L4: AM Tracking Adjustment

+ 15 hidden pages