Pioneer MLA-21 Service manual

DYNAMIC MODE

HIGH EFFICIENT

AMPLIFIER

POWER OUTPUT

DINAMIC

— OFF _ ON

LA21

STEREO POWER AMPLIFIER

STEREO POWER AMPLIFIER

M-LA21

THIS MANUAL IS APPLICABLE TO THE FOLLOWING MODEL(S) AND TYPE(S).

Type

DBDXCN AC110-127V / 220-230V / 240V With the Voltage Selector
DDXCN/AR AC110-127V / 220-230V / 240V With the Voltage Selector

Model

M-LA21 the following method.

Power Requirement

The voltage can be converted by

ORDER NO.

RRV2393

¶ This product is a system(s) component.

This product does not function properly independently ; to avoid malfunctions, be
sure to connect it to the prescribed system component(s), otherwise damage may
result.

¶ Please connect it to the STEREO CD TUNER XC-LA21, for operation inspection.
¶ System component Table

Component Model Service manual Remarks

COMPACT MINI COMPONENT X-LA21 RRV2370
STEREO CD TUNER XC-LA21 RRV2392
STEREO POWER AMPLIFIER M-LA21 RRV2393 This manual.
SPEAKER SYSTEM S-LA21 RRV2394

CONTENTS

1. SAFETY INFORMATION

.......................................

2. EXPLODED VIEWS AND PARTS LIST

3. SCHEMATIC DIAGRAM

4. PCB CONNECTION DIAGRAM

5. PCB PARTS LIST

6. ADJUSTMENT

.....................................................

..........................................

...........................

................................................

.................

12
18
19

2
3
6

7. GENERAL INFORMATION

7.1 DIAGNOSIS

..................................................

7.1.1 SINGLE OPERATION METHOD

7.1.2 DISASSEMBLY

8. PANEL FACILITIES AND SPECIFICATIONS

................................

....................................

.........

....

20
20
20
21
23

PIONEER CORPORATION 4-1, Meguro 1-chome, Meguro-ku, Tokyo 153-8654, Japan

PIONEER ELECTRONICS SERVICE, INC. P.O. Box 1760, Long Beach, CA 90801-1760, U.S.A.
PIONEER EUROPE NV Haven 1087, Keetberglaan 1, 9120 Melsele, Belgium
PIONEER ELECTRONICS ASIACENTRE PTE. LTD. 253 Alexandra Road, #04-01, Singapore 159936

c

PIONEER CORPORATION 2000

T – IZK OCT. 2000 Printed in Japan

M-LA21

1. SAFETY INFORMATION

This service manual is intended for qualified service technicians ; it is not meant for the casual do-it­yourselfer. Qualified technicians have the necessary test equipment and tools, and have been trained
to properly and safely repair complex products such as those covered by this manual.
Improperly performed repairs can adversely affect the safety and reliability of the product and may
void the warranty. If you are not qualified to perform the repair of this product properly and safely, you
should not risk trying to do so and refer the repair to a qualified service technician.

WARNING
This product contains lead in solder and certain electrical parts contain chemicals which are known to the state of California to cause
cancer, birth defects or other reproductive harm.

Health & Safety Code Section 25249.6 – Proposition 65

NOTICE
(FOR CANADIAN MODEL ONLY)
Fuse symbols (fast operating fuse) and/or (slow operating fuse) on PCB indicate that replacement parts must
be of identical designation.

REMARQUE
(POUR MODÈLE CANADIEN SEULEMENT)
Les symboles de fusible (fusible de type rapide) et/ou (fusible de type lent) sur CCI indiquent que les pièces
de remplacement doivent avoir la même désignation.

(FOR USA MODEL ONLY)

1. SAFETY PRECAUTIONS

The following check should be performed for the
continued protection of the customer and service
technician.

LEAKAGE CURRENT CHECK

Measure leakage current to a known earth ground (water
pipe, conduit, etc.) by connecting a leakage current tester
such as Simpson Model 229-2 or equivalent between the
earth ground and all exposed metal parts of the appliance
(input/output terminals, screwheads, metal overlays, control
shaft, etc.). Plug the AC line cord of the appliance directly
into a 120V AC 60Hz outlet and turn the AC power switch
on. Any current measured must not exceed 0.5mA.

Reading should
not be above

0.5mA

Earth
ground

Device
under
test

Also test with
plug reversed
(Using AC adapter
plug as required)

Leakage
current
tester

Test all
exposed metal
surfaces

ANY MEASUREMENTS NOT WITHIN THE LIMITS
OUTLINED ABOVE ARE INDICATIVE OF A POTENTIAL
SHOCK HAZARD AND MUST BE CORRECTED BEFORE
RETURNING THE APPLIANCE TO THE CUSTOMER.

2. PRODUCT SAFETY NOTICE

Many electrical and mechanical parts in the appliance
have special safety related characteristics. These are
often not evident from visual inspection nor the protection
afforded by them necessarily can be obtained by using
replacement components rated for voltage, wattage, etc.
Replacement parts which have these special safety
characteristics are identified in this Service Manual.
Electrical components having such features are identified
by marking with a
in this Service Manual.
The use of a substitute replacement component which does
not have the same safety characteristics as the PIONEER
recommended replacement one, shown in the parts list in
this Service Manual, may create shock, fire, or other hazards.
Product Safety is continuously under review and new
instructions are issued from time to time. For the latest
information, always consult the current PIONEER Service
Manual. A subscription to, or additional copies of, PIONEER
Service Manual may be obtained at a nominal charge from
PIONEER.

on the schematics and on the parts list

AC Leakage Test

2

2. EXPLODED VIEWS AND PARTS LIST

NOTES:• Parts marked by "NSP" are generally unavailable because they are not in our Master Spare Parts List.

2.1 PACKING (X-LA21)

The mark found on some component parts indicates the importance of the safety factor of the part.

•

Therefore, when replacing, be sure to use parts of identical designation.

Screws adjacent to mark on the product are used for disassembly.

•

20DDXCN/AR Only
19
16

M-LA21

9(1/2)

17

14

9(2/2)

10

3
6

5

2

7

SPEAKER

SYSTEM

TOP SIDETOP SIDE

1

4

13

FRONTFRONT

FRONTFRONT

10

11

11

15

XC-LA21
REAR

M-LA21
REAR

8(2/2)

12

12

8(1/2)

8(2/2)

12

8(1/2)

18
18

(1) PACKING PARTS LIST

Mark No. Description Part No.

1 AM Loop Antenna ANT-PMT1E-AL
2 Remote Control Unit AXD7289
3 RCA Audio Cable 122003220100

NSP 4 ‘AAA’ Size R03 Batteries 130115004000

5 FM Wire Antenna 132030001001
6 Power-cord Plug Conversion Adaptor

138011722000
7 Battery Door 500RC4603070
8 Polyform Unit 800PMT190001
9 Polyfoam (Speaker) 800PMT390000

10 Poly Foam Sheet (C) SP 801999000002

NSP 12 PE Polybag (AC Cord) 805032115000

11 Polythenefoam Sheet 801999000005

NSP 13 PE Polybag (Remocon) 805035105000
NSP 14 PE Polybag (Antenna) 805070100000
NSP 15 PE Polybag (I Book) 805085140000

16 Operating Instructions 811PMT391011

(English/Spanish/Chinese)
17 Carton See Contrast table (2)
18 Corrugate Card 815001405213
19 Additional Sheet 810PMT395010
20 Correction Sheet See Contrast table (2)

(2) CONTRAST TABLE

X-LA21/DBDXCN and DDXCN/AR are constructed the same except for the following :

Part No.

Mark No. Symbol and Description X-LA21 X-LA21 Remarks

/DBDXCN /DDXCN/AR

17 Carton 813PMT393020 813PMT393010
20 Correction Sheet Not used 810PMT395020

3

M-LA21

2.2 EXTERIOR SECTION

22

51

B

18

15

14

16

27

C

C

3

29

49

H

53

53

53

39

55

52

52

53

10

G

53

E

5

H

F

G

7

28

30

G

6

F

53

34

53

36

52

53

52

B

53

53

2

17

D

4

53

53

50

53

54

44

53

40

32

35

38

D

E

9

44

53

54

21

49

E

A

1

36

43

53

42

25

A

53

20

33(×3)

12

13

A

D

50

37

53

53
53

49

57

45

DDXCN/AR
Only

F

23

52

B

C

56
DDXCN/AR
Only

26

19

47

52

31

46
DBDXCN
Only

53

48

52

52

53

52

24

11

4

M-LA21

(1) EXTERIOR SECTION PARTS LIST

Mark No. Description Part No. Mark No. Description Part No.

2 TRANSFORMER Assy PMT1LA100031

1 AMP Assy PMT1LA100011

3 PRIMARY Assy PMT1LA100041

4 JACK Assy PMT1LA100021
5 POWER METER Assy PMT1LA100081

6 LED Assy PMT1LA100051

7 HP JACK Assy PMT1LA100111

8 • • • • •

NSP 9 PROTECTION PCB PMT1LA100141

10 S-Assy PMT3 FP01 SUBPMT3AMFP
11 Meter Assy SUBPMT3MTR

NSP 12 Heat Sink Board 033PMT1LS100

13 DC Cord 122006020060
14 Transformer (TR701) 1236C0250140
15 Fuse 124010020001

(F322, F323 : T1AL/250V)

16 Fuse 124025020001

(F328, F329 : T2.5A/250V)
17 Fuse (F321 : T3.15A/250V) 124031520003
18 Fuse 124063020001

(F324-F327 : T6.3AL/250V)
19 AC Cord See Contrast table (2)

20 Back Cover See Contrast table (2)
21 Diffuser Lens 500PMT309000
22 Top Panel 500PMT311001
23 Meter Holder 505PMT307000

24 Lens Holder 505PMT308000
25 Rectifier PCB Bracket 505PMT370000
26 PCB Bracket-R 505PMT372000
27 Mounting Bracket 505266422000
28 Power Knob 510PMT312001

29 Voltage Selector Knob 510PMT319000
30 Side Panel-L 600PMT117002
31 Side Panel-R 600PMT118002

NSP 32 Bottom Tray 600PMT302000

33 Copper Post 603PMT381000
34 Power Switch Bracket 605PMT313000

35 Transformer Bracket 605PMT317000
36 Mounting Bracket-1 605PMT373000
37 Mounting Bracket-2 605PMT374000
38 Mounting Bracket-3 605PMT375000

39 Mounting Bracket-4 605PMT376000
40 • • • • •
41 Heat Sink CDG-74 6130CDG74000
42 PCB Sheet 650PMT377000
43 Bushing 700PMT156000

44 Rubber Foot 700PMT384000
45 Strain Relief Bushing 700036022000
46 EMC Label See Contrast table (2)
47 Back Label See Contrast table (2)

NSP 48 Serial Label 809000009000

49 Screw BBZ30P100FNI
50 Screw BBZ30P180FMC
51 Screw BBZ40P060FMC
52 Screw BPZ30P100FNI
53 Screw KBZ30P060FNI

54 Foot Stand 509PMT329000
55 Holding PCB PMT1LA-100-121
56 Caution Label See Contrast table (2)
57 AC Cord Label See Contrast table (2)

(2) CONTRAST TABLE

M-LA21/DBDXCN and DDXCN/AR are constructed the same except for the following :

Part No.

Mark No. Symbol and Description M-LA21 M-LA21 Remarks

/DBDXCN /DDXCN/AR

19 AC Cord 134250220000 134220120016
20 Back Cover 500PMT303000 500PMT388000
46 EMC Label 809PMT394030 Not used
47 Back Label 809PMT396040 809PMT396060
56 Caution Label Not used 809PMT394070

57 AC Cord Label Not used 809PMT394100

5

1

M-LA21

3. SCHEMATIC DIAGRAM

A

3.1 OVERALL WIRING DIAGRAM

B

23

E

POWER METER ASSY
(PMT1LA100081)

(PH)

3

4

(PH)

4

C

From
XC-LA21

SPEAKER
OUT

L

D

5 7

IC504

BA4558N

(PH)

4

JACK ASSY

D

(PMT1LA100021)

4 4

A

7

7

18 14

IC601

STK411-230

POWER AMPLIFIER

RL601

PLY-DPDT

AMP ASSY
(PMT1LA100011)

R

4 4

6

1234

5

678

M-LA21

Note : When ordering service parts, be sure to refer to "EXPLODED VIEWS and PARTS LIST" or "PCB PARTS LIST".

A

F

LED ASSY
(PMT1LA100051)

3

(PH)

(PH)

G

HP JACK ASSY
(PMT1LA100111)

: AUDIO SIGNAL ROUTE
: AUDIO SIGNAL ROUTE (PHONES)

(PH)

PHONES

B

C

D311

From
XC-LA21

B

TRANSFORMER
ASSY
(PMT1LA100031)

C

AC IN

PRIMAY ASSY
(PMT1LA100041)

5

6

7

8

D

7

1

23

M-LA21

3.2 AMP, TRANSFORMER and PRIMARY ASSYS

4

A

B

AMP ASSY (PMT1LA100011)

A

010-550411-000A

MTZJ6.2A

MTZJ6.2A

003-030840-050

003-030840-050

2/2

BA4558DX

BA4558DX

1/2

018-030036-300A

004-022410-100

C

D

018-030036-300A

004-022410-100

CN602

136-08PMT3-200J

011-020602-001A

006-033200-63D

011-025401-000A

006-033200-80D

NJM78M12FA

NJM79M12FA

CN22

D

8

A

1234

5

678

M-LA21

: AUDIO SIGNAL ROUTE (L ch)

D

CN4

HP

HP

HP

CN604

136-07PMT3-202J

: AUDIO SIGNAL ROUTE (PHONES)

A

BA4558DX

011-024001-000A

006-033200-63D

011-025401-000A

2/2

1/2

BA4558DX

WH601

136-05PMT3-350J

CN603

136-06PMT3-200J

BZ605
MTZJ3.0A

BZ604
MTZJ3.0A

WH1

025-230041-000A

124063020001

124010020001

CN1

135-PHS060-060J

HP

TRANSFORMER ASSY

B

(PMT1LA100031)

1236C0250140

010-024001-000A

025-230041-000A

124025020001

128-1221125-000

Q610 DTA114YS
008-801144-000A

Q617 DTA114YS

008-801144-000A

122006020060

WH602

136-04PMT3-350J

CN23

D

B

C

006-033200-80D

011-020602-001A

011-020005-000A

011-020005-000A

011-020005-000A

011-020005-000A

• NOTE FOR FUSE REPLACEMENT

CAUTION -

FOR CONTINUED PROTECTION AGAINST RISK OF FIRE.
REPLACE WITH SAME TYPE AND RATINGS ONLY.

5

CN8

6

135-PHS020-020J

128-090109-000A

D311
011-024001-000A

PRIMARY ASSY (PMT1LA100041)

C

124025020001

137-400001-000J

NEUTRAL

AC IN

AC CORD

124031520003

LIVE

124250220000

D

CBA

7

8

9

1

23

M-LA21

3.3 JACK, POWER METER, LED and HP JACK ASSYS

A

JACK ASSY (PMT1LA100021)

D

004-056210-100

4

135-053259-040J

CN23

B

WH602

004-033210-100

IC504
BA4558DX

A

JK501

118-000134-003J

LR

AUDIO IN

JK502

118-020202-0001J

C

004-056210-100

MTZJ12B

IC502
BA4558DX

1/2

MTZJ9.1C

D

10

D

1234

5

678

M-LA21

A

: AUDIO SIGNAL ROUTE (L ch)

HP

: AUDIO SIGNAL ROUTE (PHONES)

E

POWER METER ASSY
(PMT1LA100081)

CN11

136-11PMT3-200J

CN2

135-PHS110-110J

B

2/2

IC502
BA4558DX

CN22

135-PHS080-080J

CN3

HP

HP

HP

A

CN602

CN12

136-17PMT3-200J

135-PHS070-070J

CN604

A

CN4

CN16

135-030060-200J

CN13

050-060060-200J

G

HP JACK ASSY
(PMT1LA100111)

CN20

135-053259-040J

110-033040-013A

CN17

110-033162-003A

HP JACK ASSY

SW501 : DYNAMIC

JK503

116-008020-000

HPHPHPHP

021-022322-000A

C

PHONES

LED ASSY

F

135-PHS070-070J

5

6

(PMT1LA100051)

7

D

GFED

8

11

1

23

M-LA21

4. PCB CONNECTION DIAGRAM

A

4.1 AMP ASSY

NOTE FOR PCB DIAGRAMS :

• Part numbers in PCB diagrams match those in the schematic
diagrams.

• The parts mounted on this PCB include all necessary parts for
several destinations.
For further information for respective destinations, be sure to
check with the schematic diagram.

• View point of PCB diagrams.

B

WH1

AMP ASSY

A

ACVL1

WH601

ACVH1

RED

W601

WHT

ACVL2

ACGND

BLU

BLK

4

ACVH2

EC625

ORN

Z1

R670

E

Q617

Z2

Connector

B

P.C.Board

C

Capacitor

Chip Part

SIDE A

SIDE B

B

CN1

16VAC1
GND
16VAC2
MUTE
CTLGND

PWRCTL

C619

CN603

BLK
BRN
RED
ORN
YEL
WHT

EC623

W604

D608

P2

D612 D611

D610

W603

D609

W602

EC620

P3

EC624

R305

D607

EC622

W605

E

IC604

IC605

E

EC621

EC633

D

W606

C618

W607

EC626

Q617

SIDE A

12

A

1234

5

678

M-LA21

EC620

P3

EC624

C622

EC626

Z1

W602

R669

Q609

R668

R621

P1

D606

W633

R667

EC614

EC618

W610

E

C603

C604

D614

W609

R672

Q616

W613

W611
BLK

E

R639

Q606

E

R635

Q610

Q607

E

E

Q605

C633

W635

C609

E

R671

W614

R625

W625

IC603

D613

DZ605

EC619

C637

R681

EC616

EC609

EC611

C607

DZ604

R629

R632

PMT1LA-01-01 AMP BOARD

EC617

W612

E

R651

Q611

Q615

E

DZ603

C608

D616

R650

R636

Q608

R657

W640

E

Q613

E

BLK.

D601

R642

E

C634

R644

E

Q603

R634

R652

R654

R653

C636

R604

Q604

R658

R662

D602

R645

R633

R638

D604

E

Q614

D615

EC613

C610

E

Q612

R630
R631

R637

R643

W626

EC610

R656

L601

R648

R647

R649
R646

R615

R616

W627

W628

C612

R641

R665

W616

W639

EC605

W634

W617

IC602

R664

R608

EC606

W629

Q602

D

RL601

W618

R609

E

R640

CN23

W619

R603

R614

C606

EC607

R663

C611

SPKR
ORN
GND
BLK

SPKL
BLK
GND
RED

R617

W630

R623

EC612

L602

EC601

C601

R618

Q601

R624

WH602

CTL GND

PWRCTL

EC630

EC631

C631

C602

E

CN602

SPKCTL

HPRCH
HPGND
HPLCH

L+R SIG

DZ602

EC602

EC615

R607

R606
R613

W638

C635

R626

R628

AGND
LIN
AGND
RIN

AGND

-12V
GND

+12V

D

R622

CN604

DZ601

C630

W623

R619

WHT
WHT

WHT
WHT
WHT
WHT

RED

R602

R605

R612
EC603

CN4

R661

W620

W621

W622

W624

R627

R601

R611

"BOND"

R659

R610

EC604

R620

EC608

A

IC601

B

C

W637

D

Q617

Q610

Q607 Q615 Q604

Q606 Q605

IC603

5

Q608

Q611 Q613 Q614 Q612

6

Q602 Q601 IC601Q609Q616

IC602Q603

7

D

CN22

A

8

13

1

23

M-LA21

4.2 TRANSFORMER and PRIMARY ASSYS

A

PRIMARY ASSY

C

B

F329

4

J2

J1

F328F329

BLK

F328

RED

ORN

YEL

PRIMARY

BLU

DANGER

D311

RL301

C315

BRN

CN9

CN8

MUTE

CTLGND

PWR

GND.

PWRCTL

PMT1LA-01-04

SW301

PRIMARY BOARD

R308

LN

C

"BOND"

C321

L301

NL

C316

F321

F321

NEUTRAL

D

SIDE A

LIVE

AC IN

14

C

1234

5

TRANSFORMER ASSY

B

PRIMARY DANGER

CN10

BLK

RED

ORN

YEL

BLU

BRN

678

M-LA21

A

PMT1LA-01-03
TRANSFORMER BOARD

PT1

F322

F325

ACVH1

RED
WHT

ACVL1
ACGND

BLK

ACVL2

BLU
ORN

ACVH2

F327

PWRCTL
GND
MUTE
16VAC2
GND
16VAC1

F323

F324

WH1

CN1

BLK

CN603

A

WH601

A

B

F326

SIDE A

C

D

B

5

6

7

8

15

1

M-LA21

4.3 JACK ASSY

A

D

JACK ASSY

23

4

CN11

E

R577

+12V

-12V

R589

CN2

J59

+12V

J78

AGND

-12V

J80

AGND

RCHOUT

AGND

LCHOUT

AGND

J81

J61
J83

CN3

+12V
METER
GND
HPLCH
HPGND
HPRCH
HPSW

B

ECHOSIG1

ECHOSIG2

VOLGND
MICSIG2

MICSIG1

MICGND

MICIN

MICSW

-6dB SW

C

E

CN12

CN604

A

R590
R597

EC562

CN22

CN602

A

EC561

R555

Q511

Q515

EC546

J564

EC531

J74

J563

R503

C549

R571

PWRCTL
METERIN

GND
HPLCH
HPGND
HPRCH

HPSW

R506

R504

R505

Q517

CN4

JACK BOARD
PMT1LA-01-02

CN23

EC559

EC560

EC537

EC548

Q518

R575

R599

C547

R561

R507

C548

R502

R576

EC541

GND
SPKL
GND
SPKR

FOR NON-KARAOKE

C529

R558
R501

R530

R529

J39

EC535

R598

R567

R593

IC504

R580

R596

C535

Q514

C539

R579

Q501

R592

EC532

EC545

Q504

EC544

R594

R552

D509

R572

Q516

C543

R560

C546

J71

C541

EC536

R520

Q513

J82

Q512

R557

R591

R551

DZ506

R545

DZ504

C519

J40

C532

J52

EC529

R554

EC549

EC523

EC521

C516

C533

C528

C531

D506

R548

EC528

R547

C518

D510

R553

IC502

EC530

EC522

D511

R581

R542

C517

TO EC522

EC527

C524

W1

C530

C525

Q502

DZ505

R584

EC526

R523

R522

R550

Q503

Z2

TO EC523

EC520

R521

J29

R549

C558

EC525

EC524

J54

Z1

C520

IC512

EC511

MSSOP36-P-450-0.A

EC515

EC514

R570

R569

EC533

EC534

J68

C557

R533

R534

EC513

R585

EC517

EC512

R586

R532

C523

"BOND"

C544

"BOND"

RIN

R588
C556

R587

J67

C545

EC518

R518

LIN

JK502

JK501

"BOND"

"BOND"

SIDE A

WH602

A

Q511

Q515

Q518

Q517

Q512

IC504

Q513

Q501 Q502

IC502

D

16

D

1234

IC512Q516 Q514

Q503Q504

1

234

4.4 POWER METER, LED and HP JACK ASSYS

LED ASSY

F

LED503

R574

POWER

E

R573

+12v

METER
ASSY

GND

LED501

DYNA

MIC

M-LA21

A

PMT1LA-01-05

LED502

CN17

PMT1LA-01-05

D

CN2

D

CN3

CN11

CN12

JK503

ECHOS1
+12V
ECHOS2
VOLGND
MICS2

-12V
MICS1
MIC GND
MIC
MIC SW
DYNAMIC

+12V
METER
LED GND
HP Lch
HP GND
HP Rch
HP SW

CN20

HP SW

HPSW

HP GND

HP Rch

HPRCH

DYNAMIC

HP Lch

HPLCH

HPGND

+12V

CN13

+12V

DYNAMIC

C551

CN14

EC557

W552

MIC GND

+12V

MIC GND
CN19
EC556

MIC

+12V

R568

-12V

MIC

R565

MIC SW

-12V
MIC SW

EC555

R564

JK504

W1
W2

W3
W4

W5
W6

W554

CN16

DYNAMIC

GND

+12v

MMETER

EC558

IC506

SW501

HP JACK ASSY

G

PMT1LA-01-11

PMT1LA-01-11

PMT1LA-01-08

PMT1LA-01-08

ECHOS1

ECHOS2

VOLGND

+12V

MICS2

-12V

MICS1

CN15

SIDE A

B

C

D

GFE

1

2

3

4

17

M-LA21

Mark No. Description Part No.

Mark No. Description Part No.

5. PCB PARTS LIST

NOTES:•Parts marked by "NSP" are generally unavailable because they are not in our Master Spare Parts List.

The mark found on some component parts indicates the importance of the safety factor of the part.

•

Therefore, when replacing, be sure to use parts of identical designation.
When ordering resistors, first convert resistance values into code form as shown in the following examples.

•

Ex.1 When there are 2 effective digits (any digit apart from 0), such as 560 ohm and 47k ohm (tolerance is shown by J=5%,
and K=10%).

560 Ω→56 × 10

47k Ω→47 × 103→ 473 ........................................................RD1/4PU 4 7 3 J

0.5 Ω→R50 .....................................................................................RN2H

1 Ω→1R0 .....................................................................................RS1P

Ex.2 When there are 3 effective digits (such as in high precision metal film resistors).

5.62k Ω→ 562 × 10

Mark No. Description Part No.

LIST OF ASSEMBLIES

AMP ASSY PMT1LA100011
TRANSFORMER ASSY PMT1LA100031
PRIMARY ASSY PMT1LA100041

JACK SSY PMT1LA100021

POWER METER AASSY PMT1LA100081

LED ASSY PMT1LA100051
HP JACK ASSY PMT1LA100111

1

→ 561 ........................................................RD1/4PU 5 6 1 J

R 5 0

1 R 0

1

→ 5621 ......................................................RN1/4PC 5 6 2 1 F

Mark No. Description Part No.

C618,C619 CKCYB103K50
C630,C631 CKCYB102K50
C636,C637 CKCYB101K50
C601,C602 CCCCH030D50
EC607-EC609,EC618 CEAT1R0M50

EC615,EC630,EC631 CEAT2R2M2A
EC603,EC604 CEAT2R2M50
EC619 CEAT100M50
EC601,EC602 CEAT101M2A
EC621,EC633 CEAT101M25

K

K

AMP ASSY

A

SEMICONDUCTORS

IC601 (STK411-230) 010-550411-000A
IC604 NJM78M12FA

IC605 NJM79M12FA

D604,D606 (RECTIFIER IN-4001B) 011-024001-000A
D607-D610 (RECTIFIER J-05) 011-020005-000A
D611,D612 (BRIDGE RECTIFIER) 011-020602-001A

IC602,IC603 BA4558DX

Q601,Q602 2SK246

Q603 DTA124ES

Q605-Q608,Q616 2SC1815

Q611-Q614 2SD1468S

Q604,Q609,Q615 2SA1015

Q610,Q617 (DTA114YS) 008-801144-000A

D602,D616 1N4148

D614,D615 (RECTIFIER IN-5401BL) 011-025401-000A

BZ604,BZ605 MTZJ3.0A

DZ601,DZ602 MTZJ6.2A

COILS

L601,L602 (3µH) 018-030036-300A

RELAY

RL601 (12V OSA-SS-212DM5) 128-122125-000A

CAPACITORS

C603,C604,C633,C634 004-022410-100

(MYLAR CAP 0.22 uF/100V)

C606,C635 CKCYB471K50

C607,C610 CKCYB682K50

C608,C609,C611,C612 CCCCH100D50

EC616 CEAT221M16
EC617 CEAT331M10
EC620,EC624 (ELECT3300µF/63V) 006-033200-63D
EC625,EC626 (ELECT3300µF/80V) 006-033200-80D
EC605,EC606,EC610-EC614 CEAT470M16

EC622,EC623 CEAT471M25

RESISTORS

R603,R605 RS2LMF101J
R608,R609,R615,R616 RS1LMF4R7J
R652,R654 RS3LMFR22J
R664,R665 RS1LMF681J
Other Resistors RD1/4PU J

OTHERS

CN602 HSG PMT3-8A JST PHR- 136-08PMT3-200J
CN604 HSG PMT3-7C JST PHR- 136-07PMT3-202J
WH602 HSG MOLEX 51067-0400 136-04PMT3-350J
WH601 HSG MOLEX 51067-0500 136-05PMT3-350J
CN603 HSG PMT3-6A JST PHR- 136-06PMT3-200J

JP WIRE AWG22 80MM B 051-275080-009J
JP WIRE AWG26 80MM B 051-675080-009J

TRANSFORMER ASSY

B

ROUND PIN 137-500001-000J

OTHERS

CN1 HEADER CTL 6 PINS 135-PHS060-060J
WH1 HEADER MOLEX 5 PINS 135-053258-050J

FUSE HOLDER 7900,HT 550-790000-000J

18

M-LA21

Mark No. Description Part No.

PRIMARY ASSY

C

SEMICONDUCTOR

D311 (RECTIFIER IN-4001B) 011-024001-000A

RELAY • SWITCH

RL301 (RELAY 9 OSA-SS-212DM) 128-090109-000A

SW301 (SLIDE SW VOLT.SELECTOR) 025-230041-000A

CAPACITORS

C315,C321 (CERAMIC CAP 0.01µF) 003-010320-250A

OTHERS

CN8 HEADER CTL 2 PINS 135-PHS020-020J

JACK ASSY

D

JP WIRE AWG22 BROWN 054-010150-010J
JP WIRE AWG22 ORANGE 054-010150-030J
JP WIRE AWG22 BLUE 054-010150-050J
JP WIRE AWG22 RED 054-010150-061J

JP WIRE AWG22 BLACK 054-010150-093J
JP WIRE AWG22 YELLOW 054-010150-100J
AC CONTACT TERMINAL 137-400001-000J
FUSE HOLDER 7900,HT 550-790000-000J

SEMICONDUCTORS

IC502,IC504 BA4558DX
Q502,Q515 DTA124ES
Q501,Q503,Q513 DTC124ES
Q504 2SA1015
Q511 DTC114ES

Mark No. Description Part No.

JP WIRE AWG26 50MM R 051-675050-006J

CN23 HEDER MOLEX 4PINS 53 135-053259-040J

POWER METER ASSY

E

JP WIRE AWG26 50MM B 051-675050-009J

OTHERS

CN11 HSG PMT3-11A JST 136-11PMT3-200J
CN12 HSG PMT3-7A JST 136-07PMT3-200J
CN13 CONN PIN 6 PINS 050-060060-200J
CN16 CONN PIN 3 PINS 050-030060-200J

LED ASSY

F

SEMICONDUCTORS

LED502,LED503 (LED-R-3MM&-S-STP)110-033040-013A
LED501 (LED-BL-3MM&-S-&&&) 110-033162-003A

RESISTORS

All Resistors RD1/4PU J

HP JACK ASSY

G

SWITCH

SW501 (PUSH BOTTON SWICH 2P2T) 021-022322-000A

OTHERS

JK503 HEADPHONE JACK ST 116-008020-000

Q512 2SC1815
Q516-Q518 2SK246
D506,D509,D510,D511 1N4148
DZ504 MTZJ9.0C
DZ505 MTZJ12B

CAPACITORS

C541,C543 CKCYB101K50
C539,C546 CKCYF103Z50
C547,C548 (MYLAR CAP 5600pF) 004-056210-100
C549 (MYLAR CAP 3300pF) 004-033210-100
C556,C557 CKCYB102K50

C533,C558 CGCYF104Z25
EC544,EC545 CEJQ2R2M50
EC532,EC548 CEJQ101M16
EC535,EC536 CEJQ220M16
EC561,EC562 CEJQ470M16

EC531,EC533,EC534,EC537 CEJQ100M16
EC546,EC559,EC560 CEJQ100M16
EC529,EC530,EC541 CEJQ1R0M50

RESISTORS

All Resistors RD1/4PU J

OTHERS

CN3,CN4 HEADER CTL 7 PINS 135-PHS070-070J
CN22 HEADER CTL 8 PINS 135-PHS080-080J
CN2 HEADER CTL 11 PINS 135-PHS110-110J
JK501 PUSH TERMINAL BOARD 118-000134-003J
JK502 PIN JACK BOARD 118-020202-001J

6. ADJUSTMENT

There is no information to be shown in this chapter.

19

M-LA21

7. GENERAL INFORMATION

7.1 DIAGNOSIS

7.1.1 SINGLE OPERATION METHOD

Please supply +9V from DC power supply to the following point.

PRIMARY ASSY

C

J2

J1

F329

F328F329

BLK

F328

RED

ORN

SW301

C321

PRIMARY
DANGER
PMT1LA-01-04
PRIMARY BOARD

NL

"BOND"

L301

C316

R308

F321

LN

F321

D311

RL301

C315

YEL

BLU

BRN

CN9

CN8

MUTE

CTLGND

PWR

GND.

PWRCTL

DC power supply

DC+9V
GND

20

7.1.2 DISASSEMBLY

× 2

1

M-LA21

× 2

× 2

× 2

1

× 2

1

10

10

10

× 2

Side Panel L
(Remove it as Side Panel R in the same way.)

2

Slide the Side Panel R
toward the rear, then

Side Panel R

Top Panel

Unhook

remove it.

× 2

× 2

1

Front Panel

3

7

10

× 2

8

10

9

Mounting Bracket-4

11

× 2

8

Mounting
Bracket

× 4

12

Remove it of
R side in the
same way.

15

Remove a Strain
Relief.

16

5

× 2

4

Disconnect a
Connector (CN8).

5

Unhook

× 2

13

13

× 4

14

13

5

× 2

6

Unhook

21

M-LA21

17

F

LED Assy

18

19

Diagnosis

D

JACK Assy

Transformer Bracket

17

22

POWER METER Assy

E

HP JACK Assy

G

B

TRANSFORMER Assy

PRIMARY Assy

C

AMP Assy

A

8. PANEL FACILITIES AND SPECIFICATIONS

8.1 PANEL FACILITIES

Front Panel

M-LA21

1

DYNAMIC MODE

HIGH EFFICIENT

AMPLIFIER

POWER OUTPUT

DINAMIC

— OFF _ ON

LA21

STEREO POWER AMPLIFIER

2

3

4

1 PHONES socket – Plug in a pair of headphones

for private listening.

2 DYNAMIC MODE indicator – Lights when the

DYNAMIC is switched on.

3 POWER OUTPUT meter – Shows the output level

of the currently selected source.

4 DYNAMIC – Switch on for extra power in the bass

and a richer treble.

23

M-LA21

8.2 SPECIFICATIONS

Power Section & Miscellaneous

Power Requirements

............................ AC 110-127/220-230/240 V (switchable),

50/60 Hz
Power Consumption (ON mode)

(Total including XC-LA21)........................... 538 W

Power Consumption (Standby mode) ............................ 1 W

Dimensions

Stereo power amplifier ......... 160(W) x 176(H) x 315(D) mm

Weight

Stereo power amplifier ................................................5.1 kg

NOTE: Specifications and design subject to possible

modification without notice, due to improvements.

24