Sony STRK-402 Service manual

STR-K402

SERVICE MANUAL

Ver 1.0 2001. 04

Manufactured under license from Dolby Laboratories Licensing
Corporation.
“DOLBY” the double-D symbol ; “AC-3” and “Pro Logic” are
trademarks of Dolby Laboratories Licensing Corporation.

SPECIFICATIONS

AUDIO POWER
SPECIFICATIONS

POWER OUTPUT AND
TOTAL HARMONIC
DISTORTION:
With 8 ohm loads, both
channels driven, from 40 ­20,000 Hz; rated 80 watts
per channel minimum RMS
power, with no more than

0.09% total harmonic
distortion from 250
milliwatts to rated output

Amplifier section

POWER OUTPUT

Rated Power Output at Stereo mode

(8 ohms 40 Hz - 20 kHz, THD 0.09%)

Reference Power Output

(8 ohms 1 kHz, THD 0.7%)

80 W + 80 W

1)

Front

: 80 W/ch

1)

Center
Surround

: 80 W

1)

: 80 W/ch

1) Depending on the sound field settings and
the sources, there may be no sound output.

Frequency response

Inputs (Analog)

2) INPUT SHORT

3) Weighted network, input level

Inputs (Digital)

MULTI CH IN, CD,
MD/TAPE, DVD/LD,
TV/SAT, VIDEO:
20 Hz – 20 kHz
0/– 0.5 dB (sound field,
and tone bypassed)

MULTI CH IN, CD,
MD/TAPE, DVD/LD,
TV/SAT, VIDEO:
Sensitivity: 250 mV
Impedance:
50 kilohms

2)

S/N

: 85 dB

(A, 250 mV

DVD/LD (coaxial):
Sensitivity: –
Impedance: 75 ohms
S/N: 100 dB
(A, 20 kHz LPF)
TV/SAT (Optical):
Sensitivity: –

3)

)

Outputs

TONE

Sampling frequency

Tuning range

Antenna terminals

Impedance: –
S/N: 100 dB
(A, 20 kHz LPF)

MD/TAPE (OUT):
VIDEO (AUDIO OUT):
Voltages: 250 mV,
Impedance:
10 kilohms
SUB WOOFER:
Voltage: 2 V
Impedance :
1 kilohms
PHONES:
Accepts low– and
high-impedance
headphones

±6 dB at 100 Hz
and 10 kHz

48 kHz (OPTICAL IN)
96 kHz (COAXIAL IN)

FM tuner section

87.5 - 108.0 MHz

75 ohms, unbalanced

US Model

Intermediate
frequency

Sensitivity

Usable sensitivity

S/N

Harmonic distortion at 1 kHz

Separation

Frequency response

Selectivity

10.7 MHz

Mono: 18.3 dBf,

2.2 µV/75 ohms

Stereo: 38.3 dBf,

22.5 µV/75 ohms

11.2 dBf, 1 µV/75 ohms

Mono: 76 dB
Stereo: 70 dB

Mono: 0.3%
Stereo: 0.5%

45 dB at 1 kHz

30 Hz - 15 kHz
+0.5/-2 dB

60 dB at 400 kHz

9-873-895-11

2001D1600-1
© 2001.4

— Continued on next page —

FM STEREO FM-AM RECEIVER

Sony Corporation

Home Audio Company
Shinagawa Tec Service Manual Production Group

STR-K402

AM tuner section

Tuning range

Antenna Loop antenna

Intermediate 450 kHz
frequency

Usable sensitivity

S/N 54 dB (at 50mV/m)

Harmonic distortion

Selectivity: At 9 kHz: 35 dB

4) You can change the AM tuning scale to 9
kHz 10 kHz. After tuning in any AM
station, turn off the receiver. Hold down the
TUNING + button and press the
button. All preset stations will be erased
when you change the tuning scale. To reset
the scale to 10 kHz (or 9 kHz), repeat the
procedure.

With 10-kHz tuning

scale:
530 - 1710 kHz

With 9-kHz tuning

scale:
531 - 1710 kHz

50 dB/m (at 1,000 kHz

or 999 kHz)

0.5% (50mV/m, 400
kHz)

At 10 kHz: 40 dB

4)

4)

Video section

Inputs Video: 1 Vp-p 75 ohms

Outputs Video: 1 Vp-p 75 ohms

General

System Tuner section:

PLL quartz-locked
digital synthesizer
system

Preamplifier section:

Low-noise NF type
equalizer

Power amplifier

section:
Pure-complementary
SEPP

Power requirements

120 V AC, 60 Hz

Power consumption

Dimensions 430 × 145 × 298 mm

Mass (Approx.)

Supplied accessories

Design and specifications are subject
to change without notice.

185 W
In Standby
Condition:
1 W

7

××

(17 7

/8 195/8 in.)
including projecting
parts and controls

7.2 kg (15 lb 14 oz)

• FM wire antenna (1)

• AM loop antenna (1)

• R6 (size-AA) batteries (2)

• Remote Commander (remote) (1)

MODEL IDENTIFICATION

— BACK PANEL —

MODEL PARTS No.

US 4-235-014-0s

Parts No.

2

STR-K402

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 A C leakage. Check leakage as
described below.

LEAKAGE

The A C leakag e from any exposed metal part to earth g round 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. F ollow the manufactur ers’ instructions to use these
instruments.

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

TABLE OF CONTENTS

1. GENERAL ··········································································4

2. TEST MODE ······································································ 6

3. DIAGRAMS

3-1. Circuit Boards Location ··············································· 8
3-2. Block Diagram Main Section····································· 9
3-3. Block Diagram Display Section······························· 10
3-4. Schematic Diagram Main Section (1/3)··················· 11
3-5. Schematic Diagram Main Section (2/3)··················· 12
3-6. Schematic Diagram Main Section (3/3)··················· 13
3-7. Printed Wiring Board Main Section ·························14
3-8. Schematic Diagram Digital Section ························15
3-9. Printed Wiring Board Digital Section ······················ 16
3-10. Schematic Diagram Display Section·······················17
3-11. Printed Wiring Board Display Section····················· 18
3-12. Schematic Diagram Video Section··························19
3-13. Printed Wiring Board Power Section ·······················19
3-14. Printed Wiring Board Video Section ························ 19
3-15. IC Block Diagrams·····················································20
3-16. IC Pin Function Description ······································ 21

4. EXPLODED VIEWS ······················································ 23

4-1. Front Panel Section ···················································· 23
4-2. Chassis Section ·························································· 24

5. ELECTRICAL PARTS LIST ·······································25

To Exposed Metal

Parts on Set

AC

0.15 µF

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

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.

1.5 kΩ

Earth Ground

Voltmeter
(0.75 V)

3

STR-K402

SECTION 1

GENERAL

This section is extracted
from instruction manual.

4

STR-K402

5

STR-K402

SECTION 2

TEST MODE

SOFTWARE VERSION DISPLAY MODE

* The software version is displayed.
* Procedure:

While depressing the TUNER and the VIDEO buttons
simultaneously, press the po wer

button to turn on the main

?/1

power . The model name, destination and the software v ersion are
displayed.

FLUORESCENT INDICATOR TUBE TEST MODE

* All fluorescent segments are tested. When this test is activated,

all segments turn on at the same time, then each segment turns on
one after another.

* Procedure:

While depressing the TV/SAT and the DVD/LD buttons
simultaneously, press the po wer
power.

1. All segments turn on.

SLEEP

SW

SP.OFF

LSLCR

( ( ( L F E ) ) )

SSR

DIGITAL

OPT COAX MULTI CH IN

PRO LOGIC DTS MPEGSTEREO MONORDS MEMORY

D

D

NAME , SURR and SOUND FIELD MODE LED turn on.

2. Press the VIDEO button, confirm display

D

SLEEP

SW

LR

L F E

S

D

PRO LOGIC MPEGSTEREO RDS

COAX

Digital Cinema Sound, SET UP and 2CH LED turn on.

3. Press the VIDEO button, confirm display

SP.OFF
C

( ( ( ) ) )

SL

DIGITAL

OPT MULTI CH IN

SR

button to turn on the main

?/1

MUTINGINFONEWSTAEQD.RANGE

dB
kHz
mft.

MHz

MUTINGINFOTAD.RANGE

k
m

MHz

DTS MONO MEMORY

NEWSEQ

dB
Hz
ft.

FACTORY SET MODE

* All preset contents are reset to the default setting.
* Procedure:

While depressing the VIDEO and the CD b uttons simultaneously ,
press the power

button to turn on the main power. The

?/1

message FACTORY appears and switch off the set.
While depressing the VIDEO and the CD b uttons simultaneously ,
press the power

button again. The message FACTORY

?/1

appears and the present contents are reset to the default values.

SOUND FIELD CLEAR MODE

* The preset sound field is cleared when this mode is activated.

Use this mode before returning the product to clients upon
completion of repair.

* Procedure:

While depressing the SOUND FIELD MODE button, press the
power

button to turn on the main power. The message

?/1

S. F. CLR appears and initialization is performed.

AM CHANNEL STEP 9 kHz/10 kHz
SELECTION MODE

* Either the 9 kHz step or 10 kHz step can be selected for the AM

channel step.

* Procedure:

Set the FUNCTION to AM. Turn off the main power.
While depressing the TUNING+ button or the
PRESET TUNING+ button, press the power

button to turn

?/1

on the main power. Either the message 9 k STEP or 10 k STEP
appears. Select the desired step.

KEY CHECK MODE

* Button check
* Procedure:

While depressing the SURR and the A.F .D b uttons simultaneously ,
press the power
“REST 36” appears.
Every pressing of any button other than ?/1 counts down the
buttons. The buttons which are already counted once are not
counted again. When all buttons are pressed “REST 00” appears.
When MASTER VOLUME is rotated in clockwise direction,
“VOL MIN”, “VOL 1” to “VOL 30”, “VOL MAX” appear.

button to turn on the main power.

?/1

MULTI CHANNEL DECODING(blue), LEVEL and A.F.D.
LED turn on.

4. Press the VIDEO button, All segments turn off.

5. Every pressing of the VIDEO b utton turns on each segment and
LED one after another in the same order.
(Not only the VIDEO button, b ut also the other b uttons such as
DVD/LD , TV/SAT , MD/TAPE , CD , TUNER can be used.)

6

SECTION 3

C

B

These are omitted.

E

Q

DIAGRAMS

THIS NOTE IS COMMON FOR PRINTED WIRING
BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this necessary note is printed in each
block.)

STR-K402

For schematic diagrams.
Note:

• All capacitors are in µF unless otherwise noted. pF: µµF
50 WV or less are not indicated except for electrolytics
and tantalums.

• All resistors are in Ω and 1/
specified.

• % : indicates tolerance.

• f : internal component.

• 2 : nonflammable resistor.

• 1 : fusible resistor.

• C : panel designation.

The components identified by mark 0 or dotted
line with mark 0 are critical for safety.
Replace only with part number specified.

• A : B+ Line.

• B : B– Line.

• H : adjustment for repair.

• Voltages and waveforms are dc with respect to ground
under no-signal (detuned) conditions.
No mark : FM

• Voltages are taken with a VOM (Input impedance 10 MΩ).
Voltage variations may be noted due to normal production
tolerances.

• Waveforms are taken with a oscilloscope.

• Circled numbers refer to waveforms.

• Signal path.

F : FM
f : CD

W or less unless otherwise

4

For printed wiring boards.
Note:

• X : parts extracted from the component side.

• a : Through hole.

• f : internal component.

• b : Pattern from the side which enables seeing.

B

CE

These are omitted.

• Waveform
– DISPLAY BOARD –

1

IC102 id

63ns

5.8Vp-p

– DIGITAL BOARD –

2

IC1005 7

81ns

5.8Vp-p

7

STR-K402

d

3-1. CIRCUIT BOARDS LOCATION

POWER SW board

HP board

STANDBY board

VIDEO board

DIGITAL boar

DISPLAY board

MAIN board

8

3-2. BLOCK DIAGRAM – MAIN SECTION –

— TUNER UNIT —

L OUT

ANTENNA

• R-CH is omitted due to same as L-CH.

• Signal Path

: FM

: CD

FM

AM

FM

AM

DATA OUT

T MUTING

R OUT

S DATA

S CLK
S LAT

STEREO

TUNED

R-CH

PLL DATA

STEREO

AUTO STOP

T MUTING

S DATA

S CLK
S LAT

CD IN

MD/TAPE OUT

MD/TAPE IN

TV/SAT

AUDIO IN

DVD/LD

AUDIO IN

VIDEO

AUDIO OUT

VIDEO

AUDIO IN

J401

J402

J403

63

IN G2

70

IN B2

61

REC OUT 2A

69

IN C2

68

IN D2

67

IN E2

62

REC OUT 2B

66

IN F2

ANALOG SOUND

PROC.
IC201

L OUT

SL OUT

STR-K402

49

MUTING

Q361

43

MUTING

Q362

L

SL

SL

A

MULTI CH IN

SUB WOOFER

FRONT

SURROUND

CENTER

DIGITAL

DVD/LD IN

DIGITAL

TV/SAT IN

J501

J1001

IC1002
IR LINK

DET

IC401(1/2)

31

IC1003

IC1003

3562

DIR DO
DIR DI
DIR CLK
DIR CE
DIR ERROR
DIR XSTATE
DIR MODE

35

IC1005

17

X1101

12.288MHz

IC1005

DIGITAL AUDIO

I/F RECEIVER

3

DIN0

4

DIN1

35

DO

36

DI

38

CLK

37

CE

34

ERROR

17

XSTATE

48

XMODE

22

12.288M

IC1004

MCLK

BCK

LRCK

DATAO

13
14
15

16

IC1005

62

DSP SO
DSP SI
DSP CLK
DSP CS
DSP CSB
DSP IC

85
83
82

84

8

67
68
69
66
65
62

AUDIO DSP

SDIA1
SDBCK0
SDWCK0

SDIA0

XI

SO
SI
SCK
CS
CSB
IC

IC1006

SBOB0
SBOB1
SBOB2

27

SW CH N IN

+5V

+5V

+5V

C

SW

IC1009

+5V

3 1

REG

IC1011

+5V

3 1

REG

IC1013

+5V

3 1

REG

IC1010

+3.3V

3 1

REG

+9.2V

50

L CH N IN

44

SL CH N IN

38

C CH N IN

60

DATA
CLOCK
S CE

SEL OUT2

59

DOUT2

58

TIN2

45

SL CH D IN

39

C CH D IN

26

SW CH D IN

32

DATA

31

CLOCK

33

LATCH

Q103,104

MUTING

CONT

AUDIO CODEC

IC1201

67

47
46
45

IC1007

SRAM

IC1201

21

CODEC CDT1
CODEC CLK
CODEC CS
CODEC DFS
CODEC PD
CODEC MUTING

29

30

39

4
5
9

6
7
8

43
42
41
11
17

3

IC1008

LIN-

LIN+

MCLK
BCK
LRCK
SDTO

SDTI1
SDTI2
SDTI3

CDT1
CCLK
DIF0/CSN
DFS
PDN
SMUTE

L OUT1

L OUT2

L OUT3

R OUT3

27

3

23

24

IC402

57

IC403

31

IC404

31

IC404

57

C OUT

SW CH OUT

Q379

MUTING
SWITCH

37

MUTING

Q363

28

MUTING

Q364

+3.3V

MONITOR

VIDEO OUT

VIDEO

VIDEO IN

VIDEO

VIDEO OUT

DVD/LD

VIDEO IN

TV/SAT

VIDEO IN

J1004

J1006

IC1014

-5V

-5V

3 2

REG

VIDEO SELECT

IC1015

10

MOUT

12

V1

5

OUT

3

V2

1

V3

-12V

2S1

13S2

4M2

M1

11

75

S1

76

S2

74

VIDEO MUTING

STEREO

AUTO STOP

66

STEREO

DATA

T MUTING

6567

62

T MUTING

AUTO STOP

TUNER DATA IN

S LAT

S CLK

S DATA

60

61

59

TUNER LAT

TUNER CLK

TUNER DATA OUT

DIR CE

DIR D1

DIR DO

DIR CLK

DIR ERR

DIR XMODE

DIR XSTATE

89

90 92 91 95 96 93 94

DIR CE

DIR D1

DIR DO

DIR CLK

DIR ERR

DIR XMODE

DIR XSTATE

DSP SI

DSP SO

24

22

DSP SO

DIR DATA0

SYSTEM CONTROL

IC102(1/2)

DSP CLK

21

DSP SI

DSP CS

25

DSP CS

DSP CLK

DSP IC

DSP CSB

99

100

DSP CSB

DSP IC

CODEC CS

CODEC CLK

CODEC CDT1

69

68

73

CODEC CLK

CODEC CDT1

CODEC PD

CODEC DFS

70

71

CODEC CS

CODEC DFS

CODEC MUTING

72

CODEC PD

CODEC MUTING

DATA

78

CLOCK

79

M CLK

M DATA

80

S CE

M CE

98

ANA/DIG

88

SYSTEM MUTING

MD1

MD2
FLASH 1
FLASH 2

+5.6V

49MD0
50
51
19
20

MD0
VDD

MD2
FLASH 1
FLASH 2

RESET

CNS105

FOR FRASH

PROGRAMMING

B

99

STR-K402

3-3. BLOCK DIAGRAM – DISPLAY SECTION –

• R-CH is omitted due to same as L-CH.

• Signal Path

: FM

R-CH

POWER AMP

IC701

+V OUT2

12

L

SLSL

A

C

8

IN2

-V OUT2

6

IN1

13

VCC

14

VCC

-V OUT1

POWER AMP

1

IN+

9

+B

IC501

+V OUT

NF2

9

11

2+V OUT1

NF1

5

3

6

IN-

2

5-V OUT

LIMITER

Q701

LIMITER

Q702

LIMITER

Q651

LIMITER

Q652

LIMITER

Q501

LIMITER

Q502

BOOSTER

Q703

BOOSTER

Q704

BOOSTER

Q653

BOOSTER

Q654

BOOSTER

Q503

BOOSTER

Q504

CURRENT

DETECT

Q705,706

CURRENT

DETECT

Q655,656

CURRENT

DETECT

Q505,506

D721

OVER LOAD

DETECT

Q708,709

OVER LOAD

DETECT

Q657,658

OVER LOAD

DETECT

Q507,509

D506

Q707

Q659

D706

D606

D731

D735

D734

RELAY
DRIVE

Q791

RELAY
DRIVE

Q730

RELAY
DRIVE

Q610

RELAY
DRIVE

Q550

RY791

RY730

RY601

RY550

R-CH

R-CH

TM602

L

R

TM601

SR

SL

C

J791

PHONES

SPEAKERS

FRONT

SPEAKERS

SURROUND

SPEAKERS

CENTER

FL101

FLUORESCENT

INDICATOR TUBE

FL1 FL2

14 29

42 31

SEG1-16

GRID1-12

DIN8CLK9STB

7

16

17

18

FL LAT

FL CLK

FL DAT

X1

X0

82 83

X101

16MHz

FL/LED DRIVE

IC103

NAME LED

SUR LED

SETUP LED

AD KEY IN1

38

FUNCTION

KEY

S100-103
S105-109

2LEVEL LED
3
1
4

D007-010

AD KEY IN2

39

FUNCTION

KEY

S110,112,113

S115-118
S121,122

LED DRIVE

AD KEY IN3

40

FUNCTION

KEY

S111,114,120

S123-129

D011 D014

LED DRIVE

Q008

Q009

3

BLU LED

41

FUNCTION

KEY

S104

S131-136

4

DCS LED

AD KEY IN4

+5V

D002 D003 D004

5

7

AFD LED

MODE LED

SYSTEM CONTROL

IC102(2/2)

VOL A1VOL B

2

1 3

VOL ENCODER

RV102

MASTER
VOLUME

6

2CH LED

PROTECT

SWITCH

IC401(2/2)

SW

POWER
MUTING

Q747,748

58

15

10

14

SP A RY

REAR RY

12

CTR RY

29

AC MUTING

PW KEY IN

56

S150

?/1

SYSTEM

POWER

PROTECT

H/P RY

5

13

WOOFER RY

Q722,723,725

7

55

HP SW

SIRCS

VCC
VCC

RESET

HSTX
STOP

POWER RY

8

D736

RY560

RELAY
DRIVE

Q560

POWER AMP

-B

FL201

-30V

TUNER

+12V

RELAY

+B

AUDIO

+5V

TUNER,RDS

VIDEO

+5V

LED
+5V

IC101

2

RESET

Q100,101

D109

D110

57

23
84

77
52
47

B

RESET

D101

CONTROL
RECEIVER

REMOTE

1

AUDIO

+7V

AUDIO

-7V

J253

-B SW
Q691

-30V REG
Q801

IC806

+12V

3 1

REG

IC807

+5V

3 1

REG

IC803

+5V

3 1

REG

IC804

+5V

3 1

REG

IC801

+7V

3 1

REG

IC802

-7V

3 2

REG

SUB WOOFER

AUDIO OUT

POWER AMP

D898

+5.6V REG

Q951

POWER

8

CONTROL

IC950

T901

D802

+B

D820-823

D824-827

VIDEO
+9.2V

VIDEO

-12V

3

5

6

D910-913

RELAY
DRIVE

Q901

FL1

FL2

F901

T902

AC
IN

D915D914

RY901

1010

STR-K402

3-4. SCHEMATIC DIAGRAM – MAIN SECTION (1/3) –

• See page 20 for IC Block Diagram.

IC B/D

(Page 13)

IC B/D

(Page 12)

IC B/D

1111