Sony STRK-840-P Service manual

STR-K740P/K840P

SERVICE MANUAL

Ver 1.0 2002. 02

• STR-K740P/K840P are the tuner and the
amplifier section in HT-DDW740/DDW840.

Dolby Laboratories Licensing Corporation.
“DOLBY” the double-D symbol ; “AC-3” and “PRO LOGIC”
are trademarks of Dolby Laboratories Licensing Corporation.

POWER OUTPUT AND TOTAL
HARMONIC DISTORTION:

With 8 ohm loads, both channels driven, from
40 – 20,000 Hz; rated 100 watts (STR-K840P
only)/80 watts (STR-K740P only) per channel
minimum RMS power, with no more than

0.09 % total harmonic distortion from 250
milliwatts to rated output (Models of area code
U only).

Amplifier section

POWER OUTPUT
Models of area code U, CA
Rated Power Output at Stereo Mode

(8 ohms 40 Hz – 20 kHz, THD 0.09 %)
STR-K840P: 100 W + 100 W
STR-K740P: 80 W + 80 W

Reference Power Output

(8 ohms 1 kHz, THD 0.7 %)
STR-K840P: FRONT

STR-K740P: FRONT

Models of area code CEL,CEK
Rated Power Output at Stereo Mode

(8 ohms 1 kHz, THD 0.7 %)
STR-K840P: 100 W + 100 W
STR-K740P: 80 W + 80 W

Reference Power Output

(8 ohms 1 kHz, THD 0.7 %)
STR-K840P: FRONT

STR-K740P: FRONT

CENTER
SURR

CENTER
SURR

CENTER
SURR

CENTER
SURR

Photo : STR-K840P (SILVER model)

SPECIFICATIONS

1)

:100 W/ch

1)

: 100 W

1)

: 100 W/ch

1)

: 80 W/ch

1)

: 80 W

1)

: 80 W/ch

2)

2)

2)

1)

: 100 W/ch

1)

: 100 W

1)

: 100 W/ch

1)

: 80 W/ch

1)

: 80 W

1)

: 80 W/ch

Models of area code AR, SP
Rated Power Output at Stereo Mode

(8 ohms 1 kHz, THD 0.7 %)
STR-K840P: 90 W + 90 W

Reference Power Output

(8 ohms 1 kHz, THD 10 %)
STR-K840P: FRONT

Models of other area code
Rated Power Output at Stereo Mode

(8 ohms 1 kHz, THD 0.7 %)
STR-K840P: 100 W + 100 W
STR-K740P: 80 W + 80 W

Reference Power Output

(8 ohms 1 kHz, THD 10 %)
STR-K840P: FRONT

STR-K740P: FRONT

1) Depending on the sound field settings and the

2) Measured under the following conditions:

US Model

Canadian Model

AEP Model

UK Model

E Model

2)

1)

: 120 W/ch

1)

CENTER
SURR

CENTER
SURR

CENTER
SURR

source, there may be no sound output.

Area code Power requirements

E 240 V AC, 50 Hz
SP, CEL, CEK, AR 230 V AC, 50 Hz
MX 120 VAC, 60 Hz

2)

: 120 W

1)

: 120 W/ch

2)

1)

: 120 W/ch

1)

: 120 W

1)

: 120 W/ch

1)

: 100 W/ch

1)

: 100 W

1)

: 100 W/ch

2)

— Continued on next page —

FM STEREO FM-AM RECEIVER

9-873-544-01

2002B1600-1

© 2002.02

Sony Corporation

Home Audio Company

Published by Sony Engineering Corporation

STR-K740P/K840P

Frequency response

MULTI CH IN3), CD,
MD/TAPE, DVD/LD,
VIDEO 1, 2

10 Hz – 50 kHz
+0.5/–2 dB (with sound
field, and tone bypassed)

Inputs (Analog)

MULTI CH IN3), CD,
MD/TAPE, DVD/LD,
VIDEO 1, 2

Sensitivity: 250 mV
Impedance: 50 kilohms

4)

: 96 dB

S/N
(A, 250 mV

5)

)

3) HT-DDW840 only

4) INPUT SHORT (with sound field and tone
bypassed).

5) Weighted network, input level.

Inputs (Digital)

DVD/LD (Coaxial)

Sensitivity: –
Impedance: 75 ohms
S/N: 100 dB
(A, 20 kHz LPF)

VIDEO 2 (Optical)

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

Outputs

MD/TAPE (OUT),
VIDEO 1

Voltage: 250 mV
Impedance: 10 kilohms

(AUDIO OUT)
SUB WOOFER

Voltage: 2 V
Impedance: 1 kilohms

Tone

Gain levels: ±6 dB, 1 dB step

FM tuner section

Tuning range 87.5 - 108.0 MHz
Antenna terminals 75 ohms, unbalanced

Intermediate Frequency

10.7 MHz

Sensitivity

Mono: 18.3 dBf, 2.2 µV/75 ohms
Stereo:

Usable sensitivity 11.2 dBf, 1 µV/75 ohms
S/N

38.3 dBf, 22.5 µV/75 ohms

Mono: 76 dB
Stereo: 70 dB

Harmonic distortion at 1 kHz

Mono: 0.3%
Stereo: 0.5%

Separation 45 dB at 1 kHz
Frequency response 30 Hz – 15 kHz,

+0.5/–2 dB

Selectivity 60 dB at 400 kHz

AM tuner section

Tuning range
Models of area code U, CA

With 10-kHz tuning scale: 530 – 1710 kHz
With 9-kHz tuning scale: 531 – 1710 kHz

Models of area code E, AR, MX

With 10-kHz tuning scale: 530 – 1610 kHz
With 9-kHz tuning scale: 531 – 1602 kHz

Models of area code MY, SP, CEL, CEK

With 9-kHz tuning scale: 531 – 1602 kHz

6)

6)

6)

6)

Antenna Loop antenna

Intermediate Frequency

450 kHz

Usable sensitivity 50 dB/m (at 1,000 kHz or

999 kHz)

S/N 54 dB (at 50 mV/m)
Harmonic distortion 0.5 % (50 mV/m, 400 Hz)

Selectivity

At 9 kHz: 35 dB
At 10 kHz: 40 dB

6) You can change the AM tuning scale to 9 kHz or
10 kHz. After tuning in any AM station, turn off
the receiver. Hold down PRESET TUNING + and
press . 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.

Video section

Inputs

Video: 1 Vp-p, 75 ohms

Outputs

Video: 1 Vp-p, 75 ohms

General

Power requirements

Area code Power requirements

U, CA, MX 120 V AC, 60 Hz
CEL, CEK 230 V AC, 50/60 Hz
MY, SP, AR 220 – 230 V AC, 50/60 Hz
E 120/220/240 V AC, 50/60 Hz

Power consumption

Area code Power consumption

U, MX STR-K840P: 210 W

STR-K740P: 180 W

CA STR-K840P: 300 VA

STR-K740P: 260 VA

CEL, CEK, MY, SP, STR-K840P: 180 W
E, AR STR-K740P: 155 W

Power consumption (during standby mode)

0.5 W

Dimensions 430 145 298 mm

(16 7/8 5 6/8 11 6/8
inches) including
projecting parts and
controls

Mass (Approx.) 7.0 kg (15 lb 7 oz)

Design and specifications are subject to change
without notice.

• Abbreviation
U : US model.
CA : Canadian model.
CEL : AEP model.
CEK : UK model.
SP : Singapore model. (Malaysia model included.)
MX : Mexican model.
MY : Malaysia model.
AR : Argentine model.

2

STR-K740P/K840P

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 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 leakag e 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)

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.

Unleaded solder

Boards requiring use of unleaded solder are printed with the lead­free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with
the lead free mark due to their particular size.)

: LEAD FREE MARK

Unleaded solder has the following characteristics.

• Unleaded solder melts at a temperature about 40°C higher than
ordinary solder.
Ordinary soldering irons can be used but the iron tip has to be
applied to the solder joint for a slightly longer time.
Soldering irons using a temperature regulator should be set to
about 350°C.
Caution: The printed pattern (copper foil) may peel away if the
heated tip is applied for too long, so be careful!

• Strong viscosity
Unleaded solder is more viscous (sticky, less prone to flow) than
ordinary solder so use caution not to let solder bridges occur such
as on IC pins, etc.

• Usable with ordinary solder
It is best to use only unleaded solder but unleaded solder may
also be added to ordinary solder.

To Exposed Metal

Parts on Set

AC

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 PAR UNE MARQUE 0 SUR LES
DIAGRAMMES SCHÉMATIQUES 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.

3

STR-K740P/K840P

MODEL IDENTIFICATION

— BACK PANEL —

Parts No.

MODEL PARTS No.

K740P : US 4-238-189-2s
K740P : Canadian 4-238-189-3s
K740P : Malaysia,Singapore 4-238-189-4s
K740P : E 4-238-189-5s
K740P : AEP 4-238-189-6s
K740P : UK 4-238-189-7s
K840P : US 4-238-193-0s
K840P : Canadian 4-238-193-1s
K840P : Malaysia, Singapore 4-238-193-2s
K840P : E 4-238-193-3s
K840P : AEP 4-238-193-4s
K840P : UK 4-238-193-5s
K840P : Argentine 4-238-193-8s
K840P : Mexican 4-238-193-9s

TABLE OF CONTENTS

1. GENERAL

·········································································· 5

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

3. DIAGRAMS ········································································ 8

3-1. Circuit Board Location ··················································8
3-2. Block Diagrams – MAIN Section – ···························· 10

– DISPLAY/POWER Section –··································· 11
3-3. Printed Wiring Board – DIGITAL Section –··············· 12
3-4. Schematic Diagram – DIGITAL Section (1/2) –·········13
3-5. Schematic Diagram – DIGITAL Section (2/2) –·········14
3-6. Printed Wiring Board – MAIN Section – ···················· 15
3-7. Schematic Diagram – MAIN Section (1/2) – ··············16
3-8. Schematic Diagram – MAIN Section (2/2) – ··············17
3-9. Printed Wiring Board – DISPLAY Section – ··············18
3-10.Schematic Diagram – DISPLAY Section – ················· 19
3-11.Printed Wiring Board – VIDEO Section – ·················· 20
3-12.Schematic Diagram – VIDEO Section – ·····················20
3-13.Printed Wiring Board – POWER Section –················· 21
3-14.Schematic Diagram – POWER Section – ··················· 22
3-15.IC Block Diagrams ······················································ 23
3-16.IC PIN FUNCTION DESCRIPTIONS ······················· 25

4. EXPLODED VIEWS ······················································ 27

4-1. Front Panel Section ····················································· 27
4-2. Chassis Section-1 ························································ 28
4-3. Chassis Section-2 ························································ 29

5. ELECTRICAL PARTS LIST ·······································30

4

SECTION 1

GENERAL

STR-K740P/K840P

This section is extracted
from instruction manual.

ALPHABETICAL ORDER

0 – 9

2 CH wh (26)

A – D

A.DEC wk (24, 26)
AM (Except for models of area

code CEL, CEK) es (31, 32)
BASS +/– wg (19, 30, 57)
CD ql (22)
CINEMA STUDIO EX A, B, C

9 (25)
Digital Cinema Sound (indicator)

qs (24)
DIMMER ej (23)
DISPLAY 2 (23, 34, 52)
Display qa (23)
DVD/LD wa (22)

E – L

ENTER wl (36)
FM (Except for models of area

code CEL, CEK) ed (31, 32)
FM/AM (Models of area code

CEL, CEK only) es (31, 32)

FM MODE (Models of area code

CEL, CEK only) ed, (Except for
models of area code CEL, CEK)

ef (32)
INPUT MODE qg (22)
IR (receptor) 4 (39, 46, 52)
LEVEL 0 (16, 20, 28, 57)

M

MASTER VOLUME wd (20, 50)
MD/TAPE qj (22)
MEMORY eh (31, 33)
MENU +/– e; (16, 28, 36, 37, 57)
MENU </> ea (16, 28, 36, 37, 57)
MODE wj (25, 30, 51)
MULTI CHANNEL DECODING

(indicator) (HT-DDW840 only)

7 (22)
MULTI CH IN (HT-DDW840

only) qf (22)
MUTING wf8 (22, 50)

N – S

NAME (36)
PHONES (jack) ek (22, 51)
PRESET/PTY SELECT +/–

(Models of area code CEL, CEK

only) 3 (33, 34)

PRESET TUNING +/– (Except

for models of area code CEL,
CEK) 3 (33, 54)

PTY (models of area code CEL,

CEK only) ef (34)
SET UP 6 (4, 16, 37, 57)
SHIFT eg (33)
SLEEP (HT-DDW740 only) qf

(37)
SURR qd (28, 57)

T – Z

TREBLE +/– qh (30, 57)
TUNER ws (22, 32, 33, 36)
TUNING +/– 5 (32)
VIDEO 1 qk (22)
VIDEO 2 w; (22)

BUTTON DESCRIPTIONS

?/1 (power) 1 (4, 15, 20, 21,

30, 31, 54)

• Abbreviation

CEK : UK model.
CEL : AEP model.

1 74 523

6

g

90qaqsqdqf qg qhqjqkqlw; waws8

+

–

ek ej eh eg ef ed es ea e; wl wk wj wh wg wf wd

5

STR-K740P/K840P

SECTION 2

TEST MODE

FACTORY PRESET MODE

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

While depressing the VIDEO 1 and the 2CH buttons simul­taneously, press the power

button to turn on the main power .

?/1

The message “FACTORY” appears and switch off the set.
While depressing the VIDEO 1 and the 2CH buttons simul­taneously, press the power

button again. The message

?/1

“FACTORY” appears and the present contents are reset to the
default values.

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+ button, press the power

button to turn on the

?/1

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

* For US/Canadian/E model only

SPEAKER SIZE SELECTION MODE

*Either Normal Speaker or Micro Satellite Speaker can be selected.
*Procedure:
While depressing the LEVEL button, press the po wer

?/1

button
to turn the main power.
Either the message “NORM. SP.” or “MICRO SP.” is displayed.
Select the desired speaker size.

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 MD/T APE and the SHIFT b uttons simul­taneously, press the 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

MULTI CHANNEL DECODING , Digital Cinema Sound ,
A.F.D. , MODE , 2CH and SET UP LED turn on.

2. Press the VIDEO button, confirm display.

D

SLEEP

SW

LR

L F E

S

D

PRO LOGIC MPEGSTEREO RDS

COAX

A.F .D. , MODE , LEVEL , SET UP , and Dig ital Cinema Sound
LED turn on.

button to turn on the main power .

?/1

dB
kHz
mft.

MHz

k
m

MHz

MUTINGINFONEWSTAEQD.RANGE

MUTINGINFOTAD.RANGE

3. Press the VIDEO button, confirm display

SP.OFF
C

( ( ( ) ) )

SL

DIGITAL

OPT MULTI CH IN

SR

DTS MONO MEMORY

NEWSEQ

dB
Hz
ft.

MULTI CHANNEL DECODING , 2CH , SURR and NAME
LED turn on.

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

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

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 MODE button, press the power

?/1

button
to turn on the main power.
The message “SURR. CLR.” appears and initialization is
performed.

DEMONSTRATION MODE

* Demonstration is performed.
* Procedure :

While depressing the SET UP button, press the power

?/1

button. The message appears and demonstration is performed.

* To finish DEMONSTRATION MODE, press the power

?/1

button while the introduction message appears in the display.

SOFTWARE VERSION DISPLAY MODE

* The software version is displayed.
* Procedure:

While depressing the ENTER and the A.F.D 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.

KEY CHECK MODE

* Button check
* Procedure:

While depressing the VIDEO 1 and the SHIFT buttons
simultaneously, press the po wer
power.
“REST 39” appears. (AEP, UK, model: “RESET 38”)
Every pressing of any button other than ?/1 and SPEAKERS
counts down the buttons. The b uttons 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 48”, “VOL MAX” appear.

button to turn on the main

?/1

6

AUTO BETICAL MODE

* This mode is installed in the Europe models only. When this mode

is used, the receiver scans the broadcasts that can be received by
the tuner, and sets up the broadcasts. Be sure to start scanning
after connecting the antenna.

* Procedure:

1. Check that the antenna is connected.

2. Press the ?/1 button to turn on the power while pressing the
MEMORY button.

3. The message “AUTO-BETICAL SELECT” appears and the
receiver starts scanning.

STR-K740P/K840P

7

STR-K740P/K840P

3-1. Circuit Board Location

SECTION 3

DIAGRAMS

POWER SW board

HEADPHONE board

STANDBY board

DISPLAY board

AC SELCT board (E model only)

VIDEO board

MAIN board

DIGITAL board

8

STR-K740P/K840P

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

For schematic diagrams.
Note:

• All capacitors are in µF unless otherwise noted. p : pF. 50

WV or less are not indicated except for electrolytics and
tantalums.

• All resistors are in Ω and

specified.

• % : indicates tolerance.

f

•

: internal component.

• 2 : nonflammable resistor.

• 5 : fusible resistor.

• C : panel designation.

Note:

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.

• 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
J : CD (ANALOG)
c : DVD (DIGITAL)

• Abbreviation

CND : Canadian model
MY : Malaysia model
SP : Singapore model
AR : Argentine model
MX : Mexican model

1

/

W or less unless otherwise

4

Note:

Les composants identifiés par
une marque 0 sont critiques
pour la sécurité.
Ne les remplacer que par une
pièce portant le numéro spécifié.

For printed wiring boards.
Note:

• X : parts extracted from the component side.

a

•

•

• : Pattern from the side which enables seeing.

Caution:
Pattern face side: Parts on the pattern face side seen from
(Side A) the pattern face are indicated.
Parts face side: Parts on the parts face side seen from
(Side B) the parts face are indicated.

: Through hole.

f

: internal component.

C

Q

B

E

B

CE

These are omitted.

These are omitted.

• Waveform

DIGITAL Board

1 IC1101 wa (XOUT)

2 IC1201 9 (MCLK1)

3 IC1601 id (XI)

81ns

(12.288MHz)

73ns (13.59MHz)

5ns (20MHz)

4.4Vp-p

3.3Vp-p

2.8Vp-p

99

STR-K740P/K840P

3-2. Block Diagrams – MAIN Section –

TUNER PACK

L CH

FM

R CH

ST-DO

AM

ST-DI

CLK

CE

STEREO

TUNED

MUTING

RDS-DATA

RDS-INT

FM SIG OUT

J201

VIDEO OUT

VIDEO IN

J200

VIDEO OUT

VIDEO IN

VIDEO IN

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

• Signal Path

: FM

: CD(ANALOG)

: DVD (DIGITAL)

AEP, UK

R-CH

1

M.OUT

13

V1

15

V1 OUT

5

V2

3

DVD

IC103

VIDEO SELECT

SW1

SW2

SW3

SW4

SW5

14

10

4

6

2

D203

ANTENNA

FM

75 Ω

COAXIAL

AM

MONITOR

VIDEO 1

VIDEO 2

DVD/LD

D204

IC1601(1/3)

SYSTEM CONTROL.

76

DO

78

SLATCH

74

STEREO

73

TUNED

75

MUTING

53

RDS DATA

52

RDS CLOCK

43

RDS SIGNAL

90

SW1

89

SW2

88

SW3

87

SW4

DIGITAL

CD

MD/TAPE

DVD/LD

VIDEO 2

VIDEO 1

MULTI

CH IN

COAXIAL

OPTICAL

IN

OUT

IN

AUDIO IN

AUDIO IN

AUDIO OUT

AUDIO IN

FRONT

SURROUND

SUB WOOFER

CENTER

DVD/LD

IN

VIDEO 2

IN

J402

J403

J404

J401

J1101

IC1105

OPTICAL

IN

93

XSTATE

XMODE

CKSEL1

DIGITAL AUDIO

5

DIN2

4

DIN1

35

DO

36

DI

38

CLK

37

CE

34

ERROR

17

XSTATE

48

XMODE

47

CKSEL1

IC1102

IC1102

35

62

98 97 95 96 99 100 94 1

DI

CE

DO

CLK

ERROR

IC1101

I/F RECEIVER

CK OUT

DATAO

XIN XOUT

22 21

X1101

12.288MHz

LRCK

IC201

ANALOG SOUND

PROC.

1

L IN8

+3.3V

L

SL

SL

C

SW

FLASH 1

FLASH 2

RESET

A

CNS3

MD0

VDD

FOR

MD2

FLASH

PROGRAMMING

L OUT

SL OUT

C OUT

SW OUT

Q379

MUTING
SWITCH

IC1604

EEPROM

SDA SCL

5 6

34 33

SDA

SP SWITCH/FLASH 1

51

Q361

MUTING

47

Q365

MUTING

39

Q363

MUTING

35

Q364

MUTING

SCL

49MD0

MD2

51

28

FLASH 2

27

2

L IN9

67

L REC3

71

L IN7

69

L IN5

63

L IN2

61

L REC1

62

L IN1

11

AL IN

13

ASL IN

16

ASW IN

15

AC IN

10

IC1501

SMUTE

29

30

39

4

5

9

6

7

8

43

42

41

17

3

AUDIO CODEC

LIN-

LIN+

MCLKI

BCK

LRCK

SDTO

SDTI1

SDTI2

SDTI3

CDT1

CCLK

CS

PD

S.MUTE

L OUT1

L OUT2

L OUT3

R OUT3

27

25

23

24

15

14

CLK

DATA

IC1502

67

-

IC1201

AUDIO DSP

22

SCK OUT

13

BCK

14

15

16

D1101

24AUDIO

20

4

5

19

HD OUT

HD IN

HCLK

7PM3

HCS

HACN

DATA0

2

18

GP9

KFSI0

29

BCKI2

28

LRCKI2

30

SDI2

69

GP8

68

GP9

35

HD OUT

33

HD IN

34

HCLK

36

HCS

32

HACN

PM

113
56

BST

2

XRST

59

EXLOCK

6

BST

XRST

14

BCKO1

20

19LRCKO

18SDI1

SDO1

23

SDO2

24

SDO3

25

MCLK1

9

MCLK2

12

IC1601(2/3)

SYSTEM CONTROL

IC1202

SRAM

X1201

13.5MHz

IC1502

21

10

12

SCL

CDT1

-

13CS8PD9

AL OUT

27

DL IN

29

DSL IN

31

DC IN

32

DSW IN

20

DATA

21

CLK

22

LATCH

Q1601,1602

MUTING

CONT

D1601

16

24

21

LATCH

ANA/DIG

F.MUTING

B

1010

– DISPLAY/POWER Section –

STR-K740P/K840P

• R-CH is omitted due to same as L-CH

• Signal Path

FL101

FLUORESCENT

INDICATOR TUBE

F1 F2

14 29

42 31

SEG1-16

GRID1-12

DIN8CLK9STB

7

IC101

BUFFER

61

62

63

DIN

CLK

FL_STB

X1

X0

82 83

X1601

20.0MHz

: FM

IC100

FL DRIVE

SW1

SW2

SW3

SW4

1

2

3

4

A/D0

38

FUNCTION

KEY

Q107-111

LED

DRIVE

29

FUNCTION

S110-119S100-109

D100-104

Q100-104
LED DRIVE

30

31

BLUE LED

MODE LED

A/D1

39

KEY

D111-114

32

AFD LED

2CH LED

26

DCS LED

A

A/D2

40

FUNCTION

KEY

S120-128

R-CH

IC701

POWER AMP

+V OUT2

12

Q701,702

LIMITER

L

SLSL

C

SW

Q747,748

POWER
MUTING

22

AC MUTING

A/D3

41

FUNCTION

KEY

S130-137,
S143,144

8

NF2

IN2

1

MUTING

-V OUT2

IC702

POWER AMP

+V OUT2

NF2

IN2

8

1

MUTING

-V OUT2

POWER AMP

IC501

+V OUT

1

IN+

67

68

PROTECTOR

HEADPHONE RELAY

SYSTEM CONTROL

IC1601(3/3)

9

11

12

9

11

6

IN-

2

5-V OUT

72

PREOUT/FRONT RELAY

3 1

ENCODER

RV102

MASTER
VOLUME

Q651,652

LIMITER

Q501,502

LIMITER

70

VOL(B)59VOL(A)

60

71

REAR RELAY

CENTER RELAY

Q703

BOOSTER

Q704

BOOSTER

Q653

BOOSTER

Q654

BOOSTER

Q503

BOOSTER

Q504

BOOSTER

69

WOOFER RELAY

POWER KEY

56

S145

?/1

IC601

21

FUSE DETECT

POWER RELAY

66

D731

D733

D734

IC601

57

SIRCS

AVCC

VCC3

VCC5

RSTX

STOP

55

54

35

84

23

77

48

B

1

RESET

Q740

AF POWER

PROTECT

SWITCH

PROTECT

Q640

AF POWER

PROTECT

Q540

AF POWER

PROTECT

25

HP DETECT

Q705,706
CURRENT

DETECT

Q655,656
CURRENT

DETECT

Q505,506
CURRENT

DETECT

D721

Q722,723,725

IC401

7

5

Q790
RELAY
DRIVE

Q710
RELAY
DRIVE

Q610
RELAY
DRIVE

Q550
RELAY
DRIVE

Q560
RELAY
DRIVE

IC102

REMOTE
CONTROL
RECEIVER

RY791

RY701

RY601

RY501

RY560

g

+3.3V(STBY)

IC1602

RESET

1 2

R-CH

R-CH

TM602

L

R

TM601

SR

SL

C

J405

PHONES

CENTER

AUDIO

OUT

+3.3V

AUDIO

+5V

K740P:AEP,UK
K840P:AEP,UK

TUNER

+3.3V

AC DET

J791

FRONT

SURROUND

SUB

WOOFER

+3.3V REG

3 1

3 1

Q921

POWER AMP

Q471

IC1503

+5V
REG

IC1905

+3.3V

REG

SPEAKERS

-B

FL101

-30V

RELAY

+B

AUDIO

+7V

AUDIO

-7V

VIDEO

+5V

VIDEO

-5V

TUNER

+10V

Q691,692

-B SW

Q801

-30V REG

+3.3V

+2.5V

+5V

IC801

+7V

1 3

REG

IC802

-7V

3 2

REG

IC807

+5V

3 1

REG

IC804

-5V

3 2

REG

IC1902

+10V

3 1

REG

IC1904

+3.3V

3 1

REG

IC1901

+3.3V

2

REG

4

+2.5V

5

REG

IC1903

+5V

3 1

REG

D802

+B

-B

D820-823

D902-905

D910-913

D914

Q901
RELAY
DRIVE

D899

D898

T901

K740P:E/K840P:E MODEL ONLY

S901

VOLTAGE

F1

F2

D915

RY901

F901

T902

SELECTOR

AC
IN

1111

STR-K740P/K840P

3-3. Printed Wiring Board – DIGITAL Section –

IC1102

IC1502

IC1501

• : Uses unleaded solder.

IC1101

IC1202

• See page 8 for Circuit Boards Location.

IC1105

• Semiconductor

Location

Ref. No. Location

D1001 A-2
D1101 A-3
D1501 B-8
D1502 B-8
D1601 E-1
D1905 F-7
D1906 E-7
D1907 E-7

IC1101 A-3
IC1102 A-1
IC1105 A-6
IC1201 C-2
IC1202 C-3
IC1501 B-2
IC1502 B-1
IC1503 C-9
IC1552 B-1
IC1601 D-1
IC1602 E-1
IC1604 F-1
IC1901 E-7
IC1902 E-6
IC1903 F-7
IC1904 E-6

Q1601 D-1
Q1602 E-1

IC1552

IC1602

IC1601

IC1201

IC1905

11P:EXCEPT K740P:AEP,UK/K840P:AEP,UK
15P:K740P:AEP,UK/K840P:AEP,UK

IC1904

K740P:AEP,UK/K840P:AEP,UK

IC1902

IC1503

IC1901

IC1604

IC1903

1212

STR-K740P/K840P

3-4. Schematic Diagram – DIGITAL Section (1/2) –

• See page 9 for Waveform. • See page 23 for IC Block Diagrams.

IC B/D

1313

STR-K740P/K840P

3-5. Schematic Diagram – DIGITAL Section (2/2) –

• See page 9 for Waveform. • See page 25 for IC Pin Function Description.

1414