Kenwood XSG-7-G, XSG-7 Service manual

STEREO AUTO REVERSE CASSETTE DECK

70%

SYSTEM

CONTROL

REC

IN

PLAY

OUT

L

R

rev. mode

Dolby NR CRLSBC

¶

1

0

2

7

3

¡

8

”

stereo auto reverse cassette deck

on/standby

front loading mechanism

X-SG7/SG7G

SERVICE MANUAL

Knob (K29-6741-04)

Phono jack (E63-0046-15)

Panel * (A29-)

Indicator (B12-0319-13)

Metallic cabinet (A01-3360-01)

Panel * (A60-)

Knob (K29-7572-13)

Power cord bushing (J42-0083-05)

Rectangular receptacle (E08-0311-05)

AC power cord * (E30-)

* Refer to parts list on page13.

Refer to X-E9 and X-SA7 service manuals (B51-4926-00/B51-5214-00), if you require in detail.

X-SG7/SG7G

LED

ITEM

POWER

DOLBY B

DOLBY C

RVS

MODE

UNDER ADJUSTMENT

PB CALIB

ERR

L

R

PB LEVEL

ERR

L

R

REC CALIB

ERR

L

R

REC LEBEL

ERR

L

R

BIAS DAC

ERR

LRPB ALL OK

ALL OK

Operation to reset

The microcomputer may fall into malfunction (impossibility to operate, erroneous display, etc.) when the power cord is unplugged while power is ON or due to an external factor. In this case, execute the following procedure to reset the microcomputer and return it to normal condition.

Unplug the power cord from the power outlet and, while holding the stop key depressed, plug the power cord again.

÷ Please note that resetting the microcomputer

clears the contents stored in it returns it to condition when it left the factory.

Audio cord (2) (E30-0615-05)

System control cord (1) (E30-2628-05)

ACCESSORIES

DISASSEMBLY FOR REPAIR

✜ Power does not turn on and tray does not come out.

1. Turn the pully in the direction of the arrow in the drawing with a finger (1).

2. If the tray comes out to the front side, pull out the tray by hand forward the front (2).

CIRCUIT DESCRIPTION

✽ Correction of circuit description LED indication state.

2

ADJUSTMENT

{

AC voltmeter AC voltmeter

Oscilloscope

Distortion meter

AG

SYSTEM

CONTROL

REC

IN

PLAY

OUT

L

R

KSJ-0816

Order Item

Input

setting

Output

setting

Deck

setting

Adjustment points Adjustment method Fig.

Unless otherwise specified, set the respective switches as follow : TAPE : NORMAL DOLBY : OFF INPUT : REC IN OUTPUT : PLAY OUT I. Cassette mechanism section (Recording/play head adjustment)

< 1 >

Demagnetization and cleaning

——

Power : OFF Demagnetization, cleaning, PLAY

Recording head, erase head, capstan, pinch roller

Demagnetize the REC/ PLAY head with the head eraser. Clean the REC/PLAY head, erase head, capstan and pinch roller using a cotton swab slightly damped with alcohol.

< 2 >

Azimuth of the REC/PLAY head

TCC-153

MTT-114

10KHz, -10dB

LINE OUT

(Lch or Rch)

PLAY

Adjust the output to maximum and adjust the azimuth adjustment screw for the Lissajous waveform pattern of the oscilloscope to become close to a 45˚ straight line.

II. Printed circuit board adjustment (X28-297)

(1)

Tape speed (normal)

TCC-110 MTT-111

3KHz

(A) PLAY MOTOR VR.

Adjust so ; that the frequency is 3KHz at the tape center.

(2) Playback level

TCC-130

400 Hz

(A)

MANUAL ADJUSTMENT MODE PLAY

ADJUSTMENT VALUE UP : [DOLBY] KEY DOWN : [RVS PLAY] KEY CHANGE OF ADJUSTMENT MODE [CRLS] KEY

Output level : -1dBs

(3) Bias current

TCC-108A

12.5KHz, -21dBm

(A)

MANUAL TEST MODE REC and PLAY

-21dBm

(4) Recording level

TCC-108A

400Hz, -21dBm

(A)

MANUAL TEST MODE REC and PLAY

-21dBm

RVS

FWD

X-SG7/SG7G

(A) Measurement Equipment Connection

✜ The method of the manual adjust-

ment mode.

(1) Setting

Shorting the TEST pin of (X28)(A/5) TP5 —w— TP4 with the diode, plug the power cord to the AC wall let.

(2) Refer to manual adjustment

mode(3-3), if require more details.

3

ACEGIBDFHJ

EB

1

64 41

24

80

65 40

25

1

110

16

13

BE

1

3

1

10

1

3

9

1

112

10

1

10

15

5

12

1810

BE

B

BE

E

19

E

B

15 1 101

I

BE

BEBE

G

O

REC IN

PLAY

OUT

SYSTEM

CONTROL

AC

OUTLET

E B

E

B

E B

E

B

E

B

BE

BEBE

EB

E

B

E

B

PC BOARD (Component side view)

1

2

3

4

5

6

7

Refer to the schematic diagram for the value of resistors and capacitors.

4 5

L M N OA BDFHCEGIJ K

REC: 5.0V OTHER: 0V

PLAY,REC, REC PAUSE: 5.0V OTHER: 0V

5.1V

4.7V

4.8V

5.1V

11.3V

0.6V

5.7V

6.1V

12.3V

12.9V

4.7V

5.1V

0V

4.8V

0V 0V

0.6V

1.3V

3.2V

3.5V

1.3V

NORMAL:2.0V METAL/CRO2:3.3V

STOP:4.4V PLAY/REC:0V

REC: 0V OTHER: 4.3V

1.2V

6.4V

REC:0V

6.4V

6.5V

1.7V

6.5V

6.5V6.5V

6.3V

12.9V

6.5V

6.2V

6.4V

7.0V

6.2V

7.0V

6.4V

6.5V

1.7V

6.5V

6.4V

REC:0V

6.4V

DOLBY OFF:0V

DOLBY ON:5.0V

DOLBY B:0V DOLBY C:5.0V

PLAY:0V

REC:5.0V

OTHER:4.3V

REC:0V

CRO2/METAL:5.0V

NORMAL:0V

25.8V

5.1V

12.6V

12.9V

REC:4.8V

REC:0V

7.9V

7.3V

12.9V

9.8V

3.7V

1.3V

0.7V

3.7V

0.7V

1.3V

PLAY:12.9V

REC:0V

PLAY:0V

REC:5.0V

REC:4.4V PLAY:0V

0.5V

0.8V

7.3V

0.6V

0.5V

0.8V

12.3V

5.0V

11.6V

12.2V

1 2 3 4 5 6 7 8 9

18

17

16

15

14

13

11 12

10

NORMAL

CRO2 METAL METAL

CRO2

NORMAL

1.9V

4.4V

3.2V

4.4V

2.4V

1.9V

2.6V 4.1V

3.2V

3.6V

12.9V

0V 12.9V

1.8V 2.9V

4.38V

2.3V 3.4V

1.7V 2.9V

2.64V 4.1V

12.9V

1.69V

MODE:RECORDING

IC8 VOLTAGE

7.0V

10u16

C229

+

C239 1u50

+

22u16

C209

+

C210

22u16

+

10u16

C233 +

10u16

C232

+

22u16

C234

+

C238 100u16

+

47u16

C21

+

C214 1u50

+

1u50

C114

+

C122 0.1u50

+

C124 0.1u50

+

C126 10u16

+

C130 0.1u50

+

C132 2.2u50

+ +

C131 2.2u50

C125 10u16

C121 0.1u50

++

1u50

C113

+

C123 0.1u50+C129 0.1u50

+

+++

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

( (

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

C158 22u35

+

()(

)

(

)

()(

)

(

)

(

)

()(

)

(

)

)()()

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

()(

)

(

)

1u50

C23

+

1u50

C24

+

C14 1u50

+

10u16

C8

+

C9

100u10

+

100u16

C5

+

)

(

)

(

)

(

)

(

)

(

)

(

)

(

) )

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

181716

15

14

13

12

10

PROTECTION CIRCUIT

THARMAL DETECTING

POWER SOURCE

STABILIZING

+15V

DET.

ABSO.

DET.

PEAK

DET.

ABSO.

123

DET.

PEAK

4

VCA

11

DRIVER

PRE

7

VCA

COMPARATOR

5

6

GND

8

9

0.022

C225

220K

R219

0.01

C221

0.022

C227

R221 33K

C223 560P

33K

C228

0.022

C226

C222

0.01

220K

R220

C224

560P

R222

C230

10P

1 2 3 4 5

6

4

1 2 3

HX

L4

150P

C218

220P

C220

16

220P

4

C219

3

2

L3

EH

C217

150P

EH

4

6

L9

3

1 25

C231 0.01

0.01

C237

22K

R226

10 1/4W

R224

10

R223

1/4W

5600P

C236

R225 22K

C235 5600P

68

R233

4.7K

R235

K1

150K

R207

390P

C205

10u16

C203

+

R205

160

R203

0.022

C207

6.2K

1 2

4

3

5

160

R204 6.2K

R206

150K

R208

390P

C206

7 8

9

6

0.022

C208

10u16

C204

+

C201 680P

R201 150K

C202 680P

R202 150K

Q31,32

10mH

L7

220P

C215

15K

R211

15K

R212

10mH

220P

C216

L8

Q44

10K

R214

10K

R213

1K

R229

10

R230

22K

R227

10

R234

R228

5.6K

1/4W

10 9 8 7 6 5 4 3 2 11112

R218 1K

R217 1K

R216 10K

R215 10K

3.3K

R231

1K

R232

Q47,48

12 11 8910 7 6 5 4 132

PLAY/REC

PLAY Lch

GND

PLAY Rch

REC Lch

REC Rch

BIAS Rch

BIAS Lch

BIAS

ERASE

EH GND

13V

1

2

3

4

5

6

GND1OUT12Vz13Vref4Fin5Rin

6

Vcc17Vcc28Vz29OUT2

10

C20 0.1

10

R45

C18 0.1

R44 1K

R42 1K

R43 1K

1/4W

123

45

R109

3.9K

C107

6800P

NC

L1

MPX

1.5K

R107

R158 18K

56

E. VOL

71

1

80

VREF

77 78 79

1A

325

4

REF

VR3

VR2

74 75 76

VR1

GND

72

73

DAC

SBIT

67

GND

VR1

68 69

70

VR2

VR3

BIAS

65 66

DAC

SBIT

64

63

1A

VREF

60

62

61

585957

REC OUT

876

10

9

B/C NR

DOLBY

12

11

IREF

13

14

VOL

RECT

EQ

LMA

+

–

SBIT DAC

EQ

REC

EQ-CONTROLER

NN

NC

17

16

15

NMHNHC

20

19

18

21

HM

22

23

24

GH

GL

GP

DAC

SBIT

25

26

27

FM

FQ

F/Q

28

29

30

BIAS

VCC

–

+

LMA

DAC

SBIT

REC OUT

B/C NR

DOLBY

545551

52

53

RECT

EQ

REC

VOL

EQ

495047

48

ADJ.

BIAS

DAC

SBIT

31

32

VCC

BIAS

33

34

35

36

GND

N

M

CONT

RESET MPX

SW

C/B

ON/OFF

44

454643

42

37

38

C

39

40

41

LOGIC

ILL

C103

10u16

+

1u50

C105

+

R103 33K

1u50

C143

+

1u50

C154

+

C104

10u16

+C106

1u50

+

C144 1u50

1.5K

R108

6800P

C108

321

4

R110

5

L2

NC

MPX

3.9K

39K

R105

39K

R106

R104 33K

C213 1u50

+

3300P

C211

3300P

C212

1.5K

C118 2200P

C116 2200P

22K

R114

0.033

C112

220P

R112 2.2K

10mH

L6

R116 560

C110

C120 2200P

R126 10K

R130

R128 4.7K

C134 1u50

+

R159 24K

C136 2.2u50

22K

R120

4.7K

R118

2.2u50

C128

+

1.1K

R122

R124 1K

R145 120K

R139

47K

GP

R140R146

51K 36K

GL

R141R147

56K 30K

GH

R142R148

68K 56K

F/Q

R143R149

43K 56K

FQ

R144R150

220K 220K

FM

NC

NN

R127 4.7K

C133 1u50

R125 10K

C119 2200P

C115 2200P

C117 2200P

R115 560

C127

R121

4.7K

R117 R119

22K

1.1K2.2u50

+

C111

C109

0.033

220P

R123 1K

47K

22K

R113

R111 2.2K

10mH

L5

C155 1u50

C156 1u50

C157 1u50

2.2u50

C135

+

C141 18P

C138 1u50

+

R132 100K

C137 1u50

+

R131 100K

R151 100K

R152 62K

R157 3.9K

C139 18P

R154 5.6K

R153 5.6K

C140 56P

R155 5.6K

C142 100P

R156 1K

29

32

39

40

41

42

46

50

3300P

R161 6.2K

0.1

12K

1.2K

R163

C146

R162

C145

47K

R160 120K

R164 22K

1

2

3

4

5

6

7

8

9

10

15 14 13 12 11

R210

R209

1

2

3

4

5

6

7

8

9

10

1

3

4

14 13

50

46

42

41

40

39

32

29

6

3

1

2

5 4

6

8 7

10

9

2 1

3

4

5

8 7

9

11 10

13 12

14

15

REC. R

MUTE +B

BIAS. R

13V

BIAS. L

CLK

DATA

ST

RESET

REC. L

LEV. L

5V

S. BUSY

S. DATA

D. GND

A. GND

PLAY. R

120/70

400/12.5k

PLAY. L

OSC ATT

OSC

LINE MUTE

REC MUTE

LEV. R

220P

C102

220P

C101

100

R102

100

R101

220P220P

C150 C149

1.2K

R133

4.7K

R137

4.7K

R138

1.2K

R134

R136

56K

R135

56K

0.01

C148

100K

R168

100K

R167

220P

C152

220P

C151

R169 56K

R166 10K

R165 10K

13

14

1

4

3

REC MUTE

LINE MUTE

1 2 3

4 5 6 7 8

9

10

13

11 12

47K

R7

4.7K

R8

3.3K

R10

47K

R9

40

41

R6 100

R5 100

R3 100

R1 100

47K

R54

R2 100

100

R41

R40

100

65

64

67

66

CLOSE

SOL

64

OPEN

CASS. SW

Fin

R. INH A

Rin

READ

AVSSCETEXNCTX

NC

73

VSS

VDD

72

A

3371347035693668376738

663965

40

DATA

63

CLK

62

PH SW

61

NC

60

OSC OUT

59

NC

58

GND

57

GND

56

GND

55

GND

54

NC

53

STB

52

DATA

51

PLAY/REC

50

BIAS

49

CLK SYSTEM IC

48

ERASE

47

PLAY SW

46

LEVEL. R

45

LEVEL. L

44

R. INH B

43

I/I

42

CPM

41

E2 PROM

SYSTEM IC

656667

R39 10K

41

R55 47K

42

43

44

45

46

47

48

49

50

51

52

R56 47K

R53 47K

R51 47K

40

38

39

59

R59 10K

15K

R52

1u50

C13

+

R38 100K

10K

R37

1K

R46

0.022

C27

1K

R27

1.5K

R26

GND

OUT IN

R22

100 1/4W

+

10u16

C4

4

VSS DATA

A23CLK

A0 A1

2

VCC

NC

1

5

6

7

8

C12 0.01

R35

22K

R33

1K

22K

R34

R29 100K

330

R32

330

R31

R30 100K

GND S.DATA S.BUSY S.GND

78

77

76

59

75

74

45

44

52

51

48

61

62

63

47K

R58

47K

R57

64

43

42

46

61 38

39

50

49

47

63

R36

1K

62

1

80

REC F

HALL OUT

SOL

HALF

GND

12V

MOTOR +

MOTOR –

COM

MODE

CrO2

METAL

REC R

OPEN CLOSE

COM

MOTOR –

MOTOR +

EH

Lch

Rch GND

EH GND

+ERASE

(BRN)

+E (BRN)

-E (BLU)

+R (GRN)

-L (ORG)

+L (RED)

Lch Rch

+12V

GND

(BLU)

-ERASE

-Rch (YEL)

+Rch (GRN)

(RED)

+Lch

-Lch (ORG)

EARTH (WHT)

-R (YEL)

GND (WHT)

1

2

3

4

5

EH

EH GND

Rch

Lch

GND

1

2

3

4 5 6 7 8 9

10

13

11 12

2

1

Rch Lch

6 5 4 3

CLOSE

OPEN

COM

MOTOR -(CCW)

MOTOR +(CW)

FEW REC

HALL OUT

SOL

HALF

GND

12V

MOTOR +(CW)

MOTOR –(CCW)

COM

MODE

CrO2

METAL

REV REC

1.2K 1W

R173

1.2K 1W

R172

R171

1.2K 1W

R129

C147

+

100u16

47K

R48

0.01

C10

C19 0.01

DOLBY HX PRO

ERASE OSC

Q45

Q46

D33

Q44

Q33

Q31

Q32

IC7 (1/2)

(2/2)

IC7

PLAY MUTE

PB EQ

RELAY SELECT.

PLAY/REC

D32

Q41

Q43

Q42

EH CONT.

Q48 Q47

CONT.

BIAS

CN12

CN11

CN5

D18D20

CN6

Q24

Q23

Q27

Q28

Q29

Q30

1

2

3

4

Lch

Rch

REC

PLAY

Rch

Lch

Q21

Q22

MUTE

D24

D23

Q25

Q26

D22

D10

D21

J2

J3

CPM CONT.

Q6

Q8

CONT.

SOLENOID

Q7

Q9

D8D9

Q11

Q12

Q10

RESET

D17

Q3

D4D19

u-COM

5V

AVR

RESET

D2D3

Q5

13V AVR

E2ROM

D12

D11

D13

D14D16

D15

SYSTEM

CONTROL

CN10CN4

MOTOR DRIVE

CN2

CN3 CN9

Lch

ERASE

HEAD

R/P HEAD

Rch

PHOTO REFLECTOR

MOTOR

S6

S5

S4

S3

S2

S1

SOL

TRAY

MOTOR

S8

S7

Lch

Rch

(BOTTOM VIEW)

IC8

(X28-2972-71) (C/5)

IC6

IC1

IC3

IC4

(X28- ) (B/5)

(X28– ) (A/5)

R/P/E HEAD HEAD PCB

MECHANISM (D40–1574 –15)

IC2

R254 1K

1

2

3

4

5

6

CAUTION: For continued safety, replace safety critical components only with manufacturer's recommended parts (refer to

7

parts list). indicates safety critical components. For continued protection against risk of fire, replace only with same type and rating fuse(s). To reduce the risk of electric shock, leakage-current or resistance measurements shall be carried out (exposed parts are acceptably insulated from the supply circuit) before the appliance is returned to the customer.

The DC voltage is an actual reading measured with a high impedance type voltmeter with a cassette loaded at playback mode. The measurement value may vary depending on the measuring instruments used or on the product. Bias circuit DC voltage is measured while in the record mode.

DOLBY and the double-D symbol are trademarks of Dolby Laboratories Licensing Corporation. Noise reduction circuit made under license from Dolby Laboratories Licensing Corporation.