Sony HCD-EP303 Service Manual

HCD-EP303

SERVICE MANUAL

Ver 1.1 2002. 11

HCD-EP303 is the amplifler, CD player, tape deck and tuner section in CMT-EP303.

SECTION

TAPE DECK

SECTION

SPECIFICATIONS

Amplifier section

AUDIO POWER SPECIFICATIONS: (U.S.A. model only)

POWER OUTPUT AND TOTAL HARMONIC DISTORTION:

with 4 Ω loads both channels driven, from 120

- 10,000 Hz; rates 6 W per channel minimum RMS power, with no more than 10% total harmonic distortion from 250 mW to rated output.

Canadian model:

Continuous RMS power output (reference)

European model:

DIN power output (rated) 4.5 + 4.5 W

Continuous RMS power output (reference)

Music power output (reference)

Other model:

The following measured at AC 230 V or AC 120 V, 50/60 Hz DIN power output (rated) 4.5 + 4.5 W

Continuous RMS power output (reference)

Outputs PHONES: Accepts headphones of (stereo mini jack) 8 Ω or more SPEAKER: Accepts impedance of 4 to

6 + 6 W (4 Ω at 1 kHz, 10% THD)

(4 Ω at 1 kHz, DIN)

6 + 6 W (4 Ω at 1 kHz, 10% THD)

13 + 13 W

(4 Ω at 1 kHz, DIN)

6 + 6 W (4 Ω at 1 kHz, 10% THD)

16 Ω

US Model

Canadian Model

AEP Model

UK Model

E Model

Australian Model

Model Name Using Similar Mechanism HCD-EP30/EP40

CD Mechanism Type CS-21SC-1280

Model Name Using Similar Mechanism HCD-EP30/EP40

Tape Transport Mechanism Type TCM125-2

CD player section

System Compact disc and digital

Laser Semiconductor laser

Frequency response 20 Hz - 20 kHz (±0.5 dB)

Tape player section

Recording system 4-track 2-channel stereo Frequency response 50 - 13 000 Hz (±3 dB),

audio system

(λ=780 nm) Emission duration: continuous

using Sony TYPE I cassette

— Continued on next page —

COMPACT DISC DECK RECEIVER

9-873-621-02

2002K1600-1

Sony Corporation

Home Audio Company

Published by Sony Engineering Corporation

HCD-EP303

Tuner section

FM stereo, FM/AM superheterodyne tuner

FM tuner section

Tuning range 87.5 - 108.0 MHz Antenna FM lead antenna Intermediate frequency 10.7 MHz

AM tuner section

Tuning range Pan-American model: 530 - 1 710 kHz

European model: 531 -1 602 kHz

Other models: 531 - 1 602 kHz

Antenna Built-in ferrite bar antenna Intermediate frequency 450 kHz

General

Power requirements North American model: 120 V AC, 60 Hz European model: 230 V AC, 50/60 Hz Australian model: 230 V AC, 50/60 Hz Mexican model: 120 V AC, 60 Hz Argentine model: 220 - 230 V AC, 50/60 Hz Other models: 230 V AC, 50/60 Hz

Power consumption U.S.A. model: 25 W Canadian model: 25 W European model: 30 W

Other models: 30 W Dimensions (w/h/d): Mass: Approx. 2.9 kg

Design and specifications are subject to change without notice.

(with the interval set at 10 kHz) 531 - 1 602 kHz (with the interval set at 9 kHz)

(with the interval set at 9 kHz)

(with the interval set at 9 kHz) 530 - 1 710 kHz (with the interval set at 10 kHz)

0.5 W (in the standby mode)

Approx. 145 × 240 × 252 mm

TABLE OF CONTENTS

1. SERVICING NOTES······················································ 4

2. GENERAL ·········································································· 5

3. DISASSEMBLY ································································ 7

3-1. Front Panel Section······················································· 7 3-2. MAIN Board ································································· 8 3-3. Tape Mechanism Deck (TCM125-2) ··························· 8 3-4. POWER Board, Power Transformer ···························· 9 3-5. DISPLAY Board, HEADPHONE Board ·····················9 3-6. CD Cabinet Section ··················································· 10 3-7. CD Mechanism Deck (CS-21SC-1280)····················· 10 3-8. Cassette Lid ······························································· 11

4. MECHANICAL ADJUSTMENTS ····························· 12

5. ELECTRICAL ADJUSTMENTS ······························· 12

6. DIAGRAMS······································································ 16

6-1. Circuit Boards Location·············································· 16 6-2. Block Diagrams ·························································· 18 6-3. Printed Wiring Board MAIN Section ························ 21 6-4. Schematic Diagram MIAN Section (1/2) ·················· 22 6-5. Schematic Diagram MIAN Section (2/2) ·················· 23 6-6. Printed Wiring Board CASSETTE Section ···············24 6-7. Schematic Diagram CASSETTE Section ·················· 24 6-8. Printed Wiring Board DISPLAY Section ·················· 25 6-9. Schematic Diagram DISPLAY Section ····················· 26 6-10. Printed Wiring Board POWER Section ····················· 27 6-11. Schematic Diagram POWER Section························ 28 6-12. IC Pin Function Description ······································· 31

7. EXPLODED VIEWS ······················································ 32

7-1. Cabinet Section ··························································· 32 7-2. Front Panel Section -1 ················································ 33 7-3. Front Panel Section -2 ················································ 34 7-4. CD Cabinet Section ···················································· 35

8. ELECTRICAL PARTS LIST ······································· 36

HCD-EP303

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.

Flexible Circuit Board Repairing

• Keep the temperature of 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.

SAFETY CHECK-OUT

After correcting the original service problem, perform the following safety checks before releasing the set to the customer: Check the antenna terminals, metal trim, “metallized” knobs, screws, and all other exposed metal parts for AC leakage. Check leakage as described below.

LEAKAGE TEST

The AC leakage from any exposed metal part to earth ground and from all exposed metal parts to any exposed metal part having a return to chassis, must not exceed 0.5 mA (500 microamperes). Leakage current can be measured by any one of three methods.

1. A commercial leakage tester , such as the Simpson 229 or RCA

WT -540A. Follow the manuf acturers’ instructions to use these instruments.

CAUTION

Use of controls or adjustments or performance of procedures other than those specified herein may result in hazardous radiation exposure.

This appliance is classified as a CLASS 1 LASER product. The CLASS 1 LASER PRODUCT MARKING is located on the rear exterior.

The following caution label is located inside the unit.

2. A battery-operated AC milliammeter. The Data Precision 245

digital multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by means of a

VOM or battery-operated AC v oltmeter . The “limit” indication is 0.75 V, so analog meters must have an accurate lo w-voltage scale. The Simpson 250 and Sanwa SH-63Trd are examples of a passive VOM that is suitable. Nearly all battery operated digital multimeters that have a 2V A C range are suitable. (See Fig. A)

To Exposed Metal

Parts on Set

0.15 µF

Fig. A. Using an AC voltmeter to check AC leakage.

1.5 kΩ

Earth Ground

Voltmeter (0.75 V)

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE WITH MARK 0 ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY .

ATTENTION AU COMPOSANT AYANT RAPPORT

À LA SÉCURITÉ! LES COMPOSANTS IDENTIFÉS P AR UNE MARQUE 0 SUR LES DIAGRAMMES SCHÉMA TIQUES ET LA LISTE DES PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE REMPLACER CES COMPOSANTS QUE PAR DES PIÈSES SONY DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU DANS LES SUPPÉMENTS PUBLIÉS PAR SONY.

HCD-EP303

SECTION 1

SERVICING NOTES

NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK OR BASE UNIT

The laser diode in the optical pick-up block may suffer electrostatic break-down because of the potential difference generated by the charged electrostatic load, etc. on clothing and the human body. During repair, pay attention to electrostatic break-down and also use the procedure in the printed matter which is included in the repair parts. The flexible board is easily damaged and should be handled with care.

NOTES ON LASER DIODE EMISSION CHECK

The laser beam on this model is concentrated so as to be focused on the disc reflective surface by the objective lens in the optical pickup block. Therefore, when checking the laser diode emission, observe from more than 30 cm away from the objective lens.

LASER DIODE AND FOCUS SEARCH OPERATION CHECK

1. Press the ?/1 button to the power ON with no disc inserted

and press the CD button.

2. Open the lid for CD.

3. Turn on SW600 as following figure.

4. Confirm the laser diode emission while observing the objecting lens. When there is no emission, Auto Power Control circuit or Optical Pick-up is broken. Objective lens moves up and down five times for the focus search.

• MODEL IDENTIFICATION – Bottom View –

PART No.

MODEL PART No.

AEP, UK models 4-235-972-0 EXCEPT AEP, UK models 4-241-498-0

TO PREVENT ‘TAPE OSCILLATION SOUND AT VOLUME’ MAXIMUM SETTING (W/O TAPE)

SW600

Headphone wire dressing:

a.) Draw the wire from Main board to Headphone board along the

bottom side of heatsink.

b.)The wire must be kept away from the top side of Cassette board

at least 30 mm.

MAIN board

heatsink

HEADPHONE board

CASSETTE board

at least 30 mm

Main unit

SECTION 2

GENERAL

HCD-EP303

This section is extracted from instruction manual.

ALPHABETICAL ORDER

A – P

Cassette compartment qd (12) CD 4 (8, 9, 13) Display Window 5 8, 9, 10) ENTER/PGM 8, 9, 10, 14) MEGA BASS (14) MUSIC MENU 9 (14) PHONES jack PRESET +/– (10, 11)

w; 8

ws qs

R – Z

Remote sensor q; REPEAT (8) SHUFFLE (8) TAPE (12) TIMER indicator (15) TUNER (10, 11, 13) TUNER MEM (10) TUNING +/– (10, 11) VOLUME control

BUTTON DESCRIPTIONS

@/1 (power) (6)

.m /M> (go back/go

forward) (8, 9)

u (play/pause) (8, 9) Z PUSH OPEN/CLOSE (8) x (stop) (8)

TAPE

M (fast forward) (12) X (pause) (12, 13) N (play) (12) z (recording) (13) m (rewind) (12) xZ (stop/eject) (12, 13)

qh qf qk

HCD-EP303

Remote control

ALPHABETICAL ORDER

A – P

CD/REMAIN (7, 8, 9, 13, 15,

16) CLOCK/TIMER + (7, 14, 15) CLOCK/TIMER – (7, 14, 15) CLOCK/TIMER/SLEEP SET

(7, 14, 15) MEGA BASS (14) MUSIC MENU (14) MUTING (14) PRESET +/– (10, 11)

8 qd

R – Z

REPEAT (8) SHUFFLE (8) TAPE (12) TIMER ON/OFF (15) TUNER/BAND (10, 11, 13) TUNER MEM/ENTER/PGM

TUNING + (10, 11) TUNING – (10, 11) VOL (volume) +/–

(7, 9, 10, 14, 15)

8 qd

BUTTON DESCRIPTIONS

m (rewind) M (fast forward)

qg (8)

. (go back) > (go forward)

qg (8, 9)

u (play/pause) qh (8, 9) @/1 (power) 3 (6) x (stop) qj (8, 9, 12)

Setting the clock

1 Turn on the system. 2 Press CLOCK/TIMER/SLEEP SET on

the remote.

3 Press CLOCK/TIMER + or – on the

remote repeatedly to set the clock.

4 Press TUNER MEM/ENTER/PGM on the

remote.

The clock starts working.

To adjust the clock

Perform from step 2.

Note

The clock settings are canceled when you disconnect the power cord or if a power failure occurs.

SECTION 3

DISASSEMBLY

• The equipment can be removed using the following procedure.

SET

HCD-EP303

3-1. FRONT PANEL SECTION

(Page 7)

3-2. MAIN BOARD

(Page 8)

3-3. TAPE MECHANISM DECK

(TCM125-2) (Page 8)

3-8. CASSETE LID

(Page 11)

3-4. POWER BOARD, POWER TRANSFORMER

(Page 9)

3-5. DISPLAY BOARD, HEADPHONE BOARD

(Page 9)

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

3-1. Front Panel Section

two screws (+BTP2.6

3-6. CD CABINET SECTION

(Page 10)

3-7. CD MECHANISM DECK

(CS-21SC-1280) (Page 10)

antenna cover cabine

10)

connector (CN203)

two screws (+K3

claw

connector (CN402)

front panel section

connector (SW600)

two screws (+K3

screw (+BVTP3

two screws (+BVTP3

10)

HCD-EP303

3-2. MAIN Board

screw (+BTP2.6 × 8)

MAIN board

connector (CN302)

connector (CN101)

connector (CN301)

connector (CN204)

claw

3-3. Tape Mechanism Deck (TCM125-2)

tape mechanism deck

connector (CN202)

two screws (+BVTP3

10)

connector (CN201)

two screws (+BTP2.6

connector (CN701)

CASSETTE boar

two screws

Open the cassette lid.

(+BVTP3

10)

3-4. POWER Board, Power Transformer

rear cabinet assy

ac cord holder

screw (+BVTP3

10)

power pwb mounting bkt

screw (+BVTP3

10)

Remove four solderings.

HCD-EP303

four screws (+BVTP3

12)

power transformer

3-5. DISPLAY Board, HEADPHONE Board

HEADPHONE board

reteiner board

screw (+PTPWH2.6

Remove four solderings.

10)

POWER board

screw (+BTP2.6

seven screws (+BTP2.6

10)

DISPLAY board

HCD-EP303

)

3-6. CD Cabinet Section

CD cabinet section

two screws (+BTP2.6

3-7. CD Mechanism Deck (CS-21SC-1280)

two spring clamps

vibration proof rubber

(pink)

four fiber washers

four pulley screws

vibration proof rubber (orange)

CD mechanism deck (CS-21SC-1280)

two spring clamps

vibration proof rubber (orange)

vibration proof rubber (pink)

two screws (BVTP3 × 10)

Remove the connector.

CD cover housing

3-8. Cassette Lid

HCD-EP303

claw

Push stop/eject key.

cassette lid

claw

HCD-EP303

)

SECTION 4

MECHANICAL ADJUSTMENTS

SECTION 5

ELECTRICAL ADJUSTMENTS

PRECAUTION

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

record/playback head pinch roller erase head rubber belts capstan idlers

2. Demagnetize the record/playback head with a head demagnetizer. (Do not bring the head magnetizer close to the erase head.)

3. Do not use a magnetized screwdriver for the adjustments.

4. After the adjustments, apply suitable locking compound to the parts adjusted.

5. The adjustments should be performed with the rated power supply voltage unless otherwise noted.

Torque Measurement

Mode Torque Meter Meter Reading

FWD CQ-102C (30 – 70 g•cm)

FWD Back Tension

FF CQ-201B (more than 60 g•cm)

REW CQ-201B (more than 60 g•cm)

CQ-102C (1.5 – 5.5 g•cm)

Tape Tension Measurement

Mode Torque Meter Meter Reading

FWD CQ-403A more than 100 g

2.95 – 6.86 mN•m

(0.42 – 0.97 oz•inch)

0.15 – 5.39 mN•m

(0.021 – 0.076 oz•inch) more than 5.89 mN•m

(more than 0.83 oz•inch) more than 5.89 mN•m

(more than 0.83 oz•inch)

(more than 3.53 oz)

PRECAUTION

1. Setting MEGA BASS switch : OFF

TAPE DECK SECTION 0 dB=0.775 V

Test tape

Type Signal Used for

WS-48A 3 kHz, 0 dB Tape Speed Adjustment P-4-A063 6.3 kHz, –10 dB Head Azimuth Adjustment

Record/Playback Head Azimuth Adjustment

Procedure:

1. Mode: Playback

test tape P-4-A063 (6.3 kHz, –10 dB)

set

HEADPHONE board PHONES jack (JK401

2. Turn the adjustment screw and check output peaks. If the peaks do not match for L-CH and R-CH, turn the adjustment screw so that outputs match within 1dB of peak.

Output level

within 1dB

L-CH peak

Screw position

R-CH peak

Ω

R-CH peak

level meter

+ –

within 1dB

Screw position

3. Mode: Playback

test tape P-4-A063 (6.3 kHz, –10 dB)

L-CH

set

R-CH

in phase

HEADPHONE board PHONES jack (JK401)

screen pattern

good wrong

Ω

135 °180

oscilloscope

–

4. After the adjustments, apply suitable locking compound to the parts adjusted.

HCD-EP303

Note: Refer to “3-8. Cassette Lid” (see page 11)

adjustment screw

Tape Speed Adjustment

Setting:

Function: T APE

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

set

frequency counte

Ω

+ –

HEADPHONE board PHONES jack (JK401)

Procedure:

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

2. Adjsut the volume in CAPSTAN/REEL motor (M201) so that the frequency counter reading becomes 3,000 Hz.

Specified Value: 2,910 to 3,090 Hz

3. Confirm that the frequency at the beginning and that at the end of tape winding are between 2,955 to 3,045 Hz.

Adjustment Location:

CAPSTAN/REE motor (M201)

Adjustment Location: Record/Playback Head.

Tape Speed Adjustment

+ 29 hidden pages