STR-WX7 - Sony Audio Service Manual (repair manual)

E Model

Australian Model

MICROFILM

STR-WX7 is the tuner and amplifier
section in MHC-WX7AV.

The following measured at AC 120, 220, 240 V 50/60 Hz
DIN power output (Rated) (FRONT)

120 + 120W (6 

Ω

 at 1kHz DIN)

Continuous RMS power output (Reference)

FRONT SPEAKER: 150 + 150W
(6 

Ω

 at 1kHz, 10% THD)

CENTER SPEAKER: 60W
(8 

Ω

 at 1kHz, 10% THD)

REAR SPEAKER: 40 + 40W
(8 

Ω

 at 1kHz, 10% THD)

Inputs

MD/VIDEO 1 IN (phono jacks): voltage
450/250mV, impedance 47k

Ω

AV INPUT AUDIO (phono jacks):
voltage 250mV, impedance 47k

Ω

MIX MIC (phone jack): sensitivity 1mV,
impedance 10k

Ω

Output

MD/VIDEO 1 OUT (phono jacks):
voltage 450/250mV, impedance 1k

Ω

PHONES (stereo phone jack): accepts
headphones of 8

Ω

 or more.

FRONT SPEAKER:
accepts impedance of 6 to 16

Ω

CENTER SPEAKER:
accepts impedance of 8 to 16

Ω

REAR SPEAKER:
accepts impedance of 8 to 16

Ω

SUPER WOOFER:
Voltage 1V, impedance 1k

Ω

Inputs

AV INPUT VIDEO (phone jack): 1Vp-p,
75

Ω

Outputs

MONITOR OUT (phone jack): 1Vp-p,
75

Ω

FM stereo, FM/AM superheterodyne tuner

Tuning range

87.5 – 108.0MHz

Antenna terminals

75

Ω

 unbalanced

Intermediate frequency

10.7MHz

Tuning range
Middle Easten models:

531 – 1,602kHz(with the MW interval set at
9kHz)
5.95 – 17.90MHz (with the SW interval set
at 5kHz)

Australian, Thai models : 531 – 1,602kHz(with the AM tuning

interval set at 9kHz)
530 – 1,710kHz (with the AM tuning
interval set at 10kHz)

Other models:

MW :
531 – 1,602kHz(with the MW tuning
interval set at 9kHz)
530 – 1,710kHz (with the MW tuning
interval set at 10kHz)
SW :
5.95 – 17.90 MHz (with the SW tuning
interval set at 5kHz)

Intermediate frequency

450kHz

Antenna

AM loop antenna
External antenna terminal

— Continued on next page —

2

........................................................................... 3

2-1.

Slideng Panel Assembly ····················································· 4

2-2.

Level Slider ········································································ 4

.............................................................. 5

4-1.

Circuit Boards Location ·················································· 9

4-2.

Block Diagrams
• Main Section ································································ 10
• Power Section ······························································ 11

4-3.

Printed Wiring Board   Main Section ························· 12

4-4.

Schematic Diagram   Main (1/2) Section ···················· 13

4-5.

Schematic Diagram   Main (2/2) Section ························· 14

4-6.

Schematic Diagram   AV/Mic Section ······························ 15

4-7.

Printed Wiring Board   AV/Mic Section ··························· 15

4-8.

Schematic Diagram   Power Amp Section ······················· 16

4-9.

Printed Wiring Board   Power Amp Section ····················· 17

4-10. Schematic Diagram   Display Section ······························ 18
4-11. Printed Wiring Board   Display Section ··························· 19
4-12. Schematic Diagram   Sliding Panel Section ····················· 20
4-13. Printed Wiring Board   Sliding Panel Section ·················· 21
4-14. Schematic Diagram   Surround Section ··························· 22
4-15. Printed Wiring Board   Surround Section ························· 23
4-16. Printed Wiring Board   Trans Section ······························· 24
4-17. Schematic Diagram   Trans Section ································· 25
4-18. IC Block Diagrams ··························································· 26
4-19. IC Pin Function ································································ 28

6-1.

Case and Sliding Panel Section ........................................ 31

6-2.

Front Panel Section .......................................................... 32

6-3.

Slide Mechanism Section ................................................. 33

6-4.

Circuit Boards and Back Panel Section ............................ 34

........................................ 35

LABEL MODEL NUMBER

No.

Saudi Arabia, Singapore,
Malaysia, Australian model

4-900-848-2

π

Thai model

4-900-848-3

π

MODEL

PART No.

!

!

Power requirements
Australian model:

240V AC, 50/60Hz

Thailand model:

220V AC, 50/60Hz

Other models:

120V or 220V or 230 – 240, 50/60Hz
Adjustable with voltage selector

Power consumption

340W

Dimensions (w/h/d)

Approx. 288 

×

 205 

×

 375mm

Mass

Approx. 8.8kg

Design and specifications are subject to change without notice.

3

1 2 3 4 5 6

7

8

9
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!¡

!™

!£

!¢

!∞

!¶ !§

@∞

@§

@¶

@•

@ª

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#¢

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!•

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2

4

5

3

1

6

7

1

 MOVIE button

2

 MUSIC button

3

 GAME button

4

 PLACE button

5

 P FILE button

6

 EFFECT ON/OFF button

7

 OPEN/CLOSE button

8

 TUNER BAND button

9

 STEREO/MONO button

!º

 TUNING MEMORY button

!¡

 KARAOKE PON/MPX button

!™

 MIC LEVEL dial

!£

 MIX MIC jack

!¢

 GROOVE button

!∞

 VOLUME dial

!§

  

)

 + button

!¶

 ENTER/NEXT button

!•

 MULTI JOG STATION dial

!ª

 

0

 – button

@º

 NON-STOP button

@¡

 EDIT button

@™

 FLASH button

@£

 PLAY MODE button

@¢

 REPEAT button

@∞

 PHONES jack

@§

 LOOP button

@¶

 CLOCK/TIMER SET button

@•

 TIMER SELECT button

@ª

 FUNCTION button

#º

 PROLOGIC button

#¡

 DSP button

#™

 DBFB button

#£

 DISPLAY/DEMO button

#¢

 I/

u

 (POWER) button

1

 SYSTEM CONTROL jack

2

 ANTENNA terminal

3

 CENTER SPEAKER terminal

4

 REAR SPEAKER terminal

5

 MONITOR OUT jack

6

 FRONT SPEAKER terminal

7

 MD/VIDEO 1 jack

4

 Follow the disassembly procedure in the numerical order given.

4

 Flat type cable (19 core)

2

 Screw (BVTP 3x8)

3

 Holder level

5

 Sliding panel assembly

Slide mechanism

1

 Push the OPEN/CLOSE button to 

open the Sliding panel assembly.

1

 Screw (BVTP2.6x8)

4

 Four screw

    (BVTP2.6x8)

5

 Holder (L) assembly

a

a

b

b

6

 Four screw (BVTP2.6x8)

7

 Holder (R) assembly

8

 Remove the Level slider direction of arrow.

2

 Screw 

    (BVTP2.6x8)

3

 Top bracket

NOTE FOR INSTALLATION :
Attach in the reverse order, but make sure the rollers (

a

, 

b

) of the

holder (L) assembly and holder (R) assembly fit into the grooves of
the level slider.