Sony Walkman wm-sr1 User manual

SERVICE MANUAL

Ver. 1.1 2005.07

RADIO CASSETTE-CORDER

US Model

Canadian Model

E Model

Chinese Model

Model Name Using Similar Mechanism WM-FX171

Tape Transport Mechanism Type MF-WMSR1-114

SPECIFICATIONS

WM-SR1

9-926-921-12

2005G05-1

Sony Corporation

Personal Audio Group

Published by Sony Engineering Corporation

– 2 –

TABLE OF CONTENTS

1. SERVICING NOTES............................................... 2

2. GENERAL ................................................................... 4

3. DISASSEMBLY ......................................................... 5

4. MECHANICAL ADJUSTMENTS....................... 9

5. ELECTRICAL ADJUSTMENTS

Tape Deck Section .......................................................... 9

Tuner Section .................................................................. 10

6. DIAGRAMS

6-1. Block Diagram – TUNER Section – ............................. 11

6-2. Block Diagram – MAIN Section – ................................ 13

6-3. Printed Wiring Board ...................................................... 18

6-4. Schematic Diagram ......................................................... 21

7. EXPLODED VIEWS................................................ 27

8. ELECTRICAL PARTS LIST ............................... 29

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.

SECTION 1

SERVICING NOTES

In this set, the S301 (TAPE POWER switch) detects REC/PLAY-

BACK on.

It is mounted on the MAIN board, and therefore the REC/PLAY-

BACK on cannot be detected with the MAIN board removed.

When making an operation check and voltage check of mechani-

cal deck with the MAIN board removed, fix the S301 at turn on.

S301

– MAIN BOARD (Component Side) –

Flexible Circuit Board Repairing

• Keep the temperature of the soldering iron around 270 ˚C dur-

ing 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.

– 3 –

MODEL IDENTIFICATION

FM MODE

FM SENS

MADE IN MALAYSIA

or no indication

– Rear View –

CF1

mark

Mark Center frequency

red 10.70 MHz

blue 10.67 MHz

orange 10.73 MHz

black 10.64 MHz

white 10.76 MHz

HOW TO CHANGED THE CERAMIC FILTERS

This model is used two ceramic filters of CF1 and X1.

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.

Model Indication of S2 Indication of country origin Indication of service manual

US FM SENS MADE IN MALAYSIA US

Canadian FM SENS MADE IN MALAYSIA CND or Canadian

E FM MODE MADE IN MALAYSIA E

Saudi Arabia FM MODE MADE IN MALAYSIA EA or Saudi Arabia

5E FM SENS MADE IN MALAYSIA 5E

9E FM MODE No indication 9E

Chinese FM MODE MADE IN MALAYSIA CH or Chinese

– 4 –

SECTION 2

GENERAL This section is extracted from

instruction manual.

LOCATION OF PARTS AND CONTROLS

*1 FM MODE: E, Saudi Arabia, 9E, Chinese Models

FM SENS: US, Canadian, 5E Models

– 5 –

CABINET (REAR) ASSY

NOTE FOR INSTALLATION

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

• CABINET (REAR) ASSY

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

SECTION 3

DISASSEMBLY

• This set can be disassembled in the order shown below.

Cabinet

(Rear) Assy Main Board

Dial Pointer Setting

Mechanism Deck

(MF-WMSR1-114)

“Holder Sub Assy, Cassette”

Belt, Motor (M901),

“Head, Magnetic” (HRP901)

Set

On installation cabinet (rear) assy adjust

the S2, S305, S307, S308, S310 and knob

(AVLS), knob (PAUSE STOP).

two screws

(B1.7

cabinet (rear) ass

Remove the cabinet (rear) assy

(Release all claws from

in alphabetical order.)

2

Insert the precision screw driver (1.4 mm flat-blade) into

the slit at claw

and release the claw.

Note: Apply cloth or spacer

at the tip of the driver

not to break the claw.

S310

S308

S305

S307

cabinet (rear) ass

knob (AVLS)

knob (PAUSE STOP)

knob (AVLS)

– 6 –

MAIN BOARD

DIAL POINTER SETTING

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

connector

(CN302)

screw

(M1.4)

Remove four solders

of motor (M901).

two claws

flexible board

(CN301)

main board

Turn the tuning knob

fully in the arrow direction.

Mount the pointer

as shown in the figure

pointer guide rib

fig.

– 7 –

MECHANISM DECK (MF-WMSR1-114)

BELT, MOTOR (M901), “HEAD, MAGNETIC”(HRP901)

2

Remove the mechanism deck

(MF-WMSR1-114) to direction

of the arrow

1

two claw

belt

motor

(M901)

two special head screws

(M1.4)

two special head screws

(M1.4)

“head, magnetic”

(HRP901)

– 8 –

“HOLDER SUB ASSY, CASSETTE”

NOTE FOR INSTALLATION

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

• “HOLDER SUB ASSY, CASSETTE”

Portion

to release

the hinge plate.

spring (torsion)

“holder sub assy, cassette”

Insert a precision screw driver (1.4 mm flat-blade)

vertically into portion

to release the hingeplate.

3

“holder sub assy, cassette”

Attach the spring (torsion)

as shown in the figure.

Insert the spring (torsion)

in the ditch to direction of the arrow

Mode Torque meter Meter reading

FWD 20 – 30 g•cm

(0.28 – 0.41 oz•inch)

FWD CQ-102C 0.4 – 2.0 g•cm

Back Tension (0.006 – 0.02 oz•inch)

REV 20 – 30 g•cm

(0.28 – 0.41 oz•inch)

REV CQ-102RC 0.4 – 2.0 g•cm

Back Tension (0.006 – 0.02 oz•inch)

FF CQ201B More then 40 g•cm

REW (more than 0.6 oz•inch)

– 9 – – 10 –

SECTION 4

MECHANICAL ADJUSTMENT

PRECAUTION

1. Clean the following parts with a denatured-alcahol-moistened

swab :

Playback head Pinch roller

Rubber belt Capstan

2. Demagnetize the playback head using a demagnetizer.

3. Do not use a magnetized screwdriver for adjustments.

4. After adjusting, apply screw-locking compound onto the ad-

justed parts.

5. Unless specified otherwise, use a specified voltage (3.0V) to

perform the adjustments.

Torqu Measurement

SECTION 5

ELECTRICAL ADJUSTMENTS

Tape Speed Adjustment

Setting:

function switch: TAPE

Procedure:

1. Playback WS-48A (tape center) in the FWD state.

2. Adjust RV601 so that the frequency counter reading becomes

3,000 Hz.

Specification Values:

3. Check that deflection of the frequency counter reading between

the beginning and the end of tape is within 1.5% (apporox. 45

Hz).

Adjustment Location:

PRECAUTION

1. Specified voltage : 2.5 V (DC)

2. Setting

VOLUME dial : maximum

SPEAKER switch : OFF

AVLS switch : NORM

MEGA BASS switch : OFF

PB EQ switch : NORM

PAUSE switch : off

ISS : 1

FM SENS switch : DX (US, CND, 5E)

FM MODE switch : ST (E, 9E, EA, CH)

3. Abbreviation

CH : Chinese

CND : Canadian

EA : Saudi Arabia

5E : Refer to “Model Identification” on page 3.

9E : Refer to “Model Identification” on page 3.

TAPE DECK SECTION 0 dB=0.775 V

Test tape

Type Signal Used for

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

Frequency counter

2,985 Hz to 3,015 Hz

TUNER SECTION 0 dB=1 µV

[FM]

Setting:

function switch : FM

[AM]

Setting:

function switch : AM

• 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:

FM FREQUENCY COVERAGE ADJUSTMENT