Onkyo K-501-A Service manual

SERVICE MANUAL

SERVICE MANUAL

CASSETTE T APE DECK

K-501A

Ref. No. 3718

112001

MODEL

UPP
UDT
UGT

230-240V AC, 50Hz
120V AC, 60Hz
220-230V AC, 50/60Hz

K-501A

SAFETY-RELATED COMPONENT
WARNING!!

COMPONENTS IDENTIFIED BY MARK ON THE
SCHEMATIC DIAGRAM AND IN THE PARTS LIST ARE
CRITICAL FOR RISK OF FIRE AND ELECTRIC SHOCK.
REPLACE THESE COMPONENTS WITH ONKYO
PARTS WHOSE PART NUMBERS APPEAR AS SHOWN
IN THIS MANUAL.
MAKE LEAKAGE-CURRENT OR RESISTANCE
MEASUREMENTS TO DETERMINE THAT EXPOSED
PARTS ARE ACCEPTABLY INSULATED FROM THE
SUPPLY CIRCUIT BEFORE RETURNING THE
APPLIANCE TO THE CUSTOMER.

SPECIFICATIONS

K-501A

Track format

4-tracks, 2-channels

Erasing system

AC erase

Tape speed

4.8 cm/sec.

Wow and flutter

0.1 % (WRMS)

0.2 % (DIN)

Frequency response

Metal position tape

30 to 15,000 Hz ± 3 dB

High position tape

30 to 14,000 Hz ± 3 dB

Normal position tape

30 to 13,000 Hz ± 3 dB

Signal to noise ratio

• 54 dB (metal position tape, Dolby NR
off)

• Noise reduction of 10 dB above 5 kHz
and 5 dB at 1 kHz is possible with Dolby
B NR.

• Noise reduction of 20 dB at 5 kHz is
possible with Dolby C NR.

Input Jacks

LINE IN: 2

Input sensitivity: 500 mV
Input impedance: 50 kohms

Output Jacks

LINE OUT: 2

Standard output level: 500 mV
Output load impedance:

over 50 kohms

Motors

DC servo motor: 1

Heads

REC/PB: Special Hard Permalloy: 1
Erase head: Ferrite: 1

Power supply rating

AC 230-240 V, 50 Hz
AC 220-230 V, 50/60 Hz
AC 120 V, 60 Hz

Power consumption

13 W (230-240 V, 50 Hz)

(220-230 V, 50/60 Hz)

14 W (120 V, 60 Hz)

x

Dimensions (W H D)
155 mm x 94 mm x 303 mm
6-1/8" x 3-11/16" x 11-15/16"

(AC 230-240 V, 50Hz)

(AC 220-230 V, 50/60Hz)
155 mm x 94 mm x 297.5 mm
6-1/8" x 3-11/16" x 11-11/16"

(AC 120 V, 60Hz)

Weight

2.5 kg, 5.5 lbs

Specifications and external appearance are
subject to change without notice as a result of
product improvement.

x

SERVICE PROCEDURES

CIRCUIT NO. PART NO. DESCRIPTION
F901 252074 2A-SE-EAK,Fuse <PP,GT>

<PP>...Europian model only
<DT>...120V model only
<GT>...220-230V model only

P ANEL VIEW

FRONT PANEL

K-501A

STANDBY/ON button
STANDBY indicator

/ Rec/Pause button

FADE button/FADE indicator

ALBUM button/ALBUM indicator

STEREO CASSETTE TAPE DECK

CASSETTE LOADING MECHANISM

STANDBY / ON

BC

STANDBY

CD DUBBING

ALBUM

Rec/Pause indicator

Cassette in indicator

Eject button

FADEREV MODEDOLBY NR

DOLBY NR indicator
DOLBY NR button

REV MODE indicator
REV MODE button

Auto space button

Cassette slot

Forward/reverse side play button

-

K

5 01

Stop button

Fast-forward/Rewind Skip button

A

,

,

K-501A

EXPLODED VIEW

P901A

A9

S1

F901

P702AP702A

P703A

U2

T901

S4

S2

A17

A19

A7

A18

U1

S1

P101A

U3

S1

A16

A2

A15

S3

A14

S1

S1

A8

Z1

A5

A6

S1

A2

A17

A3

A4

A11

A1

A12

A13

A10

PARTS LIST

EXPLODED VIEW

REF. NO. PART NO. DESCRIPTION

27111266

A1

27191165

A2

28198948

A3

28148505

A4

27180583

A5

28325983

A6

27100415

A7

27191164

A8

27300750

A9
A10
A11
A12
A13
A14
A15
A16
A17
A18

27212366
28198939
28198946
28198947
28184832
28140079
28141492
28141489
27122947A
27122948A
27122949A

A19

F901

260208

252074
P101A 2009990714
P702A 20022392618
P703A 20022391010

Front bracket
Holder (Door)
Facet(IN)
Door
Spring
Recording button ass'y
Chassis
Holder (Mechanism)
#2271,Bushing
Front panel
Facet(S)
Facet(PLAY)
Facet(NR)
Cover
Cushion
Cushion
Cushion
Rear panel <DT>
Rear panel <GT>
Rear panel <PP>
Binder
2A-SE-EAK,Fuse <PP,GT>
NSAS-14P0999,Socket ass'y
NSAS-26P0998,Socket ass'y
NSAS-10P0997,Socket ass'y

P901A 253334HRK AS-CEE,Power supply cord <PP,GT>

253331HDK or

253330MIL

T901 2301571

2301572

2301573

U1 1N283583-1B

1N283583-1C

1N283583-1D

U2 1N283584-1B

1N283584-1C

1N283584-1D

U3 1N283585-1B

1N283585-1C

1N283585-1D

244248A

Z1

838130088

S1

830440089

S2

838930088

S3

838430088

S4

AS-UC-2,Power supply cord <DT>
AS-UC-2,Power supply cord <DT>
NPT-1434D,Power Transformer <DT>
NPT-1434G,Power Transformer <GT>
NPT-1434P,Power Transformer <PP>
NAAF-7383-1B,Main circuit PC board <DT>
NAAF-7383-1C,Main circuit PC board <GT>
NAAF-7383-1D,Main circuit PC board <PP>
NAPS-7384-1B,Power supply PC board <DT>
NAPS-7384-1C,Power supply PC board <GT>
NAPS-7384-1D,Power supply PC board <PP>
NADIS-7385-1B,Display circuit PC board <DT>
NADIS-7385-1C,Display circuit PC board <GT>
NADIS-7385-1D,Display circuit PC board <PP>
CMAL2Z815A,Cassette Mechanism
3TTB+8B,Self tapping screw
4TTC+8C(BC),Self tapping screw
3TTB+8B(UN),Self tapping screw
3TTB+8B(BC),Self tapping screw

K-501A

Note
<PP>...Europian model only
<DT>...120V model only
<GT>...220-230V model only

THE COMPONENTS IDENTIFIED BY MARK ARE
CRITICAL FOR RISK OF FIRE AND ELECTRIC SHOCK.
REPLACE ONLY WITH PART NUMBER SPECIFIED.

EXPLODED VIEW

CASETTE MECHANISM

K-501A

F REC

METAL

PACK

C

R REC

PARTS LIST

REF.NO PART NO. DESCRIPTION

1 FF18W- F/R belt
2 FF19Y- Main belt
3 F567-626 Switch PC board ass'y
4 FF26K- Flywheel ass'y
5 F513-891 Recording/Play head ass'y
6 F514-129 Pinch roller R
7 F514-130 Pinch roller L
8 F522-064 Clutch
9 F522-052 Clutch

10 FD52Y- Master cam

BLOCK DIAGRAM

K-501A

R/P HEAD

X

IN

LINE

OUT

ERASE HEAD

X

POWER TRANSFORMER

and REGULATOR

P.B.AMP.

Q101

BIAS OSC and HX PRO

Q401 Q405

L401,L402,L403

T901

D901,D902

70/120

Q103,Q104

12V(for SIGNAL)

Q901

12V(for MECHA)

P.B.LEVEL

R115,R116

5V(for MICROPROCESSOR)

Q905Q903

DOLBY NR,REC EQ,METER AMP

Q201Q102

MICROPROCESSOR

Q701

KEY CONTROL&DISPLAY

D801-D810

S717

AUTO

ADJUSTMENT

START KEY

TAPE SPEED

R716

MECHA and DRIVER

Q705
Q706
Q712
Q713

Q703
Q704

D905,D906

-22V(for FL tube)
Q906

K-501A

K-501A

NNORM16 NR ON/OFF45

12K

A

SCHEMATIC DIAGRAM 1

1

U1

Main circuit PC board

X

X

P

X

P101

2

9

REC L

REC R

3

(1/2W)

R410 47

C421

100/500

R418

39K

45

123

6

L403

NLO-2059

4

P401

P

C420

123/100

C419

47/16

C103

2.2/50

C101 681

R101100K

5

6

7

8

Q101

C412

121/100

L402

NCH-4183

4

6
123

11121314151617

Q401 MPC1297CA

8

910

L401

123

4

10

R413

47/16

(1/2W)

C427 183

C411

121/100

4.7

R416

6

Q405

4.7

R417

C414

C104

2.2/50

R/P

MPC1330HA

101/100

7

C409

101/100

2SC1213C

R103

C102

681

R102

100K

4

C410

C408

273

6

C407

273

NCH-4183

2SC1213C

470

R104

470

Q404

P.B.LEVEL

3

273

C406

R404
330K

5

R403

330K

273

L405

C423
C425

223

C418

BCD

C243 1000/16

INPUT(R)

INPUT(L)

OUTPUT(R)

OUTPUT(L)

P204

Q102MPC1228HA

R ch L ch

5

6

7

8

183

DTC114TS

C114

10/16

C413

100/16

C422

10/16

R405

3.3K

2SA950

R412

5.6K

Q402

DTC114YS

R106
390K

R108

C106

822

C108
100/16

R110

120

22K

R408

R411 39K

Q403

BIAS ON/OFF

8.9

R409

BIAS_CONT

C113

15K

R406

3.3K

220/6.3

470/16

120

C415

(1/2W)

R117 120

(1/2W)

R112

C110

1.5K
10/16

R120

1.5K

R114

3.9K

R116
47KB

C112

Q104

70/120

1

2

R118 1K

R/P

471

C404

R402

100K

103

C402

18

1

2

3

4

R401

100K

103

C401

471

C405

C403

22K

R407

4.7MH

681
680

472

39K

R414

C417

C416 472

39K

R415

4

15K

R107

100/16

3

C107

R109

R105

390K

C105

822

120

70/120

12V

C426

680

C424

681

L406

4.7MH

2

C109

10/16

P.B.LEVEL

R113

C111

DTC114TS

REC_L

DAC_R

70/120

R/P

1

Q103

REC_R

DAC_L

R111

1.5K

R115

3.9K
47KB

183

70/120

R119

1.5K

R285
R221
R283
R284

4.7K

4.7K

4.7K

4.7K

223

C282

C248

C283 223

104

Q203

NC

153

C246

400/12K

UDZS4.7B

D203

DTA114YS

LINE MUTE

R222

R214

2.2K

R213

2.2K

C238

R219

1.8K

Q207
DTC114YS

R278

10K

18K

C228

R212

R211 68K

C227

1/50

Q205

2SD655

OSC

R270 6.8K

Q206

2SD655

1.8K

R220

L204

NMC-6079

123

R216

C232

C230 10/16

1/50

C226

68K

C225

1/50

C229
C231

R215

123

L203

NMC-6079

R269 6.8K

R276

330K

C247

394

Q204

DTA114YS

R218

54
6

3.3K

10/16

10/16

10/16

10/16
10/16

3.3K

6
54

R217

R267

R275

1K

1K

6.8K

6.8K

390K

R274

OSC_OUT

R268 1K

10/16

C242

C241

C281

R281

REC_MUTE

222

104

C210

C208

C204

222

R202 22K

61
62
63
64

RPI[R]PBIN65

66

VRI2[R]ACCUIN

67

CONT[R]68
VRI1[R]LINEIN69
GND270
GND171
VRI1[L]LINEIN72
CONT[L]73
VRI2[L]ACCUIN74

75

RPI[L]PBIN76
77
78
79
80

R201 22K

C203

222

10/16

222

C207

1/50

1K

REC_R

C206

C205

104

C209

CLK

2.2/50

HLSL6 HLSR 55

REC_L

C218

1K

R208

6.8K

R206

1/50

C216

HA12169FB

LLSL7 LLSR 54

RECOUT[L]8 RECOUT[R]53

1/50

C215

6.8K

R205

R207

C220 1/50

Q201

LMIN[L]9 LMIN[R] 52

C219 1/50

1K

P706A

LMDET[L]10 LMDET[R]51

LEVEL_R

2

10
11
12
13

100K

R271

1

3
4
5
6
7
8
9

100K

R272

10/16

C235 4.7/50

C224

C222

10/16

R210

10K

DGND47

EQCONT[L]13 EQCONT[R]48

EQIN[L]12 EQIN[R] 49

EQOUT[L]15 EQOUT[R]46

IREF14

LMOUT[L]11 LMOUT[R]50

10K

4.7/50

C233

R209

10/16

12K

R279

C221

R273

12K

10/16

R223

C223

LEVEL_L

P706

C214

104

C212 104

560R203 560

222

R204

BIA_TRAPL1 BIA_TRAPR60

PBOUT[L]2 PBOUT[R]59

SS1L3 SS1R 58

SS2L4 SS2R 57

CCRL5 CCRR 56

222

C213

104

C217

C211 104

2.2/50

DAC_L

DAC_R

STB

DO

RESET

5

P901A

NC: No used

NAAF-7383

U2

Power supply circuit
PC board

T901

FUSE_B

2A/250V

FUSE A FUSE B

FUSE_A

NPT-1434*

245

6

7

*
NPT-1434D<DT>
NPT-1434G<GT>
NPT-1434P<PP>

AC-H

AC0

AC-G

P901

F901B

F901

F901A

AC0

P902

NAPS-7384

C901

104

5.6V

12V

GND

R916

D908

R914

R917 10K

560

D909

1SS352

470

R915

470

AC1 AC1

AC2 AC2

D910

UDZS5.6B

C916

10/16

1SS352

104

C904

C903

104

C917

D901

GP1N4003

104

D902

GP1N4003

C905

4700/25

PING

P903A

P903

C907

78M12

I

Q903

G

E854

+12VSIG

12V

O

C909

1000/16

Q901
78M12

I

O

G

1000/16

22V

GND3

MUT

12V1

12V2

12V3

GND2

5.6

R725

330K

C701

2.2/50

Q710

DC1

Q905

78M05

DC1

O

I

G

C915

100/16

D706

1SS352

DTC114YS

C702

223

R726

Q711

DTA114YS

C703

223

3.9K

K-501A

H

3

1K

6

8K

R

K

1/501/50

A

SCHEMATIC DIAGRAM 2

TEST POINT

P205

LCHRCH

R229

R234

2.2M

R734

D202

56K

2.2M

2.7K

C234

4.7/50

1SS352

3.3K

R265

47K

56K

12V

C239

104

R225

100K

68K

R256

NC

NC

R257 2.2M

680K

R246

56K

R247

68K

R237

47K

100K

NC

R236

100K

3.9K

R703

3.9K

R702

3.9K

R733

2.7K

R732

2.7K

R731

100K

4.7/50

4.7/50

R272

10/16

C235

100K

R271

1

3
4

5
6

7
8
9
10
11

C236

C224

C222

10/16

R210

10K

C/B 44

DGND47

BIASADJ[H] 37
BIASADJ[M] 36
BIASADJ[N] 35

BIASCONT[R]33

BIASCONT[L] 28

EQCONT[L]13 EQCONT[R]48

EQIN[L]12 EQIN[R] 49

EQOUT[L]15 EQOUT[R]46

IREF14

LMOUT[L]11 LMOUT[R]50

N.HIGH17

N.NORM16 NR_ON/OFF45

10K

4.7/50

C233

R209

10/16

12K

R279

C221

R273

12K

12K

10/16

R223

R227
10K

C223

LEVEL_L

P706

1

C220 1/50

.

Q201

A12169FB

2

LMDET[L]10 LMDET[R]51

LMIN[L]9 LMIN[R] 52

1/50

C219

205 6.8

1K

R207

LEVEL_R

3

P706A

2

4

12
13

S

1M

R280

4.7/50

C237

R233

R232 10K

MPX43

RST42

STB41

DATA40
CLK 39
INJ 38

GND 34

DACOUT[R]32

VCC2
VCC1 30

DACOUT[L]29

FM 27
FQ 26

F/Q 25

GH 24
GL 23
GP 22

N.MTL18

19

20

D201

R282

1M

DTC114TS

Q209

C249

10K

31

21

1SS352

223

Q210

DTC114TS

R266

R254

R255

R244

NC
R245 2.2M

R235

5

3

R704

2.7K

R228
10K

R264
47K

R226

100K

R258

82K

R248

68K

R238

33K

R735

R736 3.3K

R224

12K

C250
223

C240

R259
33K

R249
39K

R239
33K

C709 104

10K

5V

R231

R230

104

10K

10K

DOL_B1
TAPE_IN2
R.PLY13
R.PLY24
F.PLY15
F.PLY26
NC17
NC28
NC39

NC410
NC511
NC612
NC713
DOOR_LOCK_OPEN14
P-OFF15
R.REC16
MTL_SW17
F.REC18
NC819

BCD

NOTE

U1

Main circuit PC board

68K

82K

82K

NC

DOL_C63

DI21

NC

STBY62

ALBUM61

LED

TMP87CH14F

CS23

DO22

56

R262

R263 2.2M

R252

R253 390K

R242

R243

REC59

VDD58VSS26

FADE60

Q701

STB24

TEST[VSS]25

CST8.00MG

12

34
Q702

7

8

#1,#8 NC

390K

100K

2.2M

5V

X701

390K

NC

NC

NC

VAREF57

XIN27

KEY254

VASS56

KEY3[NC]55

BIAS_CONT49

LINE_MUTE46

REC_MUTE42

CLOSE_SW40

ROT.SEN.37

DOOR_CLOSE36

DOOR_OPEN35

RESET29

CASS_IN30

XOUT
28

LM[R] 51
LM[L] 50

70/120 47

OSC_OUT45
400/12K 44
DOL_RST43

OPEN_SW41

RI_OUT39

RI_IN 38

HIGH_SW31 KEY153

R260

NC
R261 2.2M

R250

R2512.2M
R241

R240 2.2M

64

REV.M

CLK20

BR93LC46F-WE2

FT52

R/P 48

SOL 34
CAP 33

32

3.9K

R706

R705

PLAY

R707

3.9K

3.9K

R727

3.9K

R730

2.7K

R729

R737

R728

2.7K

5V

Q703

2SA933

10K

Q704

DTC114YS

R712

2.7K

1M

R723

2.7K

.

THECOMPONENTS
REPLACEONLY

.

VOLTAGE(MEASUREDWITHVOLTMETER) IS

.

ALL PNP TRANSISTORS ARE EQUIVALENT

.

ALL NPN TRANSISTORS ARE EQUIVALENT TO 2SC1815-GR UNLESS OTHERWISE NOTED.

.

ALL DIODES ARE EQUIVALENT TO 1SS133 UNLESS OTHERWISE NOTED.

.

ELECTROLYTIC CAPACITORS ()ARE IN F/WV.

.

ALL CAPACITORS ARE IN pF/50WV UNLESS OTHERWISE NOTED.

EX) 030-3pF 330-33pF 331-330pF 333-0.033uF

.

ALL RESISTORS ARE IN OHMS 1/4WATTS UNLESS OTHERWISE NOTED.

.

THE THICK LINES ON PC BOARD ARE THE PRINTING SIDE OF THE PARTS.

EX) PRINTING SIDE

.

CIRCUIT IS SUBJECT TO CHANGE FORIMPROVEMENT.

R804

R803

R802

FT-1

S717

FT-2

R724

390

R746

3.9K

R745

3.9K

223

C704

R708

10K

R709

22K

12V

R801

IDENTIFIED

WITH PART

P705

470

820

470

820

RI

1MH

L702

R722

D708

NC

L701

223

223

5V

R713 3.9K

Q712

DTC114YS

1MH

Q708

DTA114YS

C710

R718

SOL

Q713

R714

C711

CAP

ARECRITICAL FOR

BYMARK

NUMBERSPECIFIED.

TO 2SA1015-GR UNLESS OTHERWISE NOTED.

U3

Display circuit
PC board

P705A

GND4

STBY

DOLBY NR

REV.MODE

AUTO SPACE

REC/PAU

RI

P701

3

2

C918

223

R744

390K

UDZS5.6B

R721

D703

1SS352

47K

9

8

7

6

5

Q707 TA7291S

4

3

2

1

47K

R717
Q706

3.9K
2SB1068

DTC114YS

1SS352

D701

47K

SAFETY

DCVOLTAGE.(NO INPUT SIGNAL)

u

NC:Noused

D803

R807

470

D804

R808

270

R809

R810

R811

R812

R805

R806

S801

S802

S803

S804

S805

SEL6910D

270

D805

470

D806

D807

470

D808

470

D809

470

470

D810

D802

D801

S806

S807

390

R813

S808

470

R814

S810

820

R815

S809

1K

R816

S811

S812

S813

NADIS-7385

1

470

Power
supply
circuit
PC board

R750
100K

UDZS7.5B

D702

R720

1.8K

C705

100/16

R751

100K

12V

TAPE SPEED ADJ.

R715

12K

R716

5KB

Q705

P702

2SB1068

LOAD OUT
LOAD IN
LOAD OUT SW
GND
LOAD IN SW

P703

MTR SPEED A
MTR SPEED B
GND
MTR
PLAY SW
5V
ROT SEN
SOL
HIGH SW
CASS IN SW
F.REC SW
MTL SW
R.REC SW

SEL6910D

SEL6910D

SLV332VR

SLV332VR

SEL6910D

DOLBY B

SEL6910D

TAPE IN

SEL6910D

SEL6910D

SEL6910D

U2

REC

FADE

ALBUM

STANDBY

DOLBY C

REV.MODE

R.PLAY

F.PLAY

EJECT

390

R817

FF

470

R818

REW

820

R819
R.PLAY

1K

R820

F.PLAY

1.8K

R821

STOP

R822

3.9K
ALBUM

10K

R823

FADE

TO MECHANISM

TO MECHANISM