PIONEER KEH-1900, KEH-1950 Service Manual

Service	KEH-1900/X1M/UC
Manual	ORDER NO.
	CRT2424

HIGH POWER CASSETTE PLAYER WITH FM/AM TUNER

KEH-1900 X1M/UC

KEH-1950 X1M/ES

- This service manual should be used together with the following manual(s):

Model No.	Order No.	Mech. Module	Remarks
CX-644	CRT1800	2M	Cassette Mech. Module:Circuit Description, Mech.Description, Disassembly

CONTENTS

1.	SAFETY INFORMATION............................................		2	7. GENERAL INFORMATION.......................................		32
2.	EXPLODED VIEWS AND PARTS LIST ......................		2	7.1 DISASSEMBLY ..................................................		32
3.	BLOCK DIAGRAM AND SCHEMATIC DIAGRAM ....		8	7.2 PARTS ................................................................		33
4.	PCB CONNECTION DIAGRAM................................		18	7.2.1	IC ...............................................................	33
5.	ELECTRICAL PARTS LIST........................................		26	7.2.2	DISPLAY ...................................................	36
6.	ADJUSTMENT .........................................................		30	8. OPERATIONS AND SPECIFICATIONS....................		37
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 ELECTRONIC [EUROPE] N.V. Haven 1087 Keetberglaan 1, 9120 Melsele, Belgium
PIONEER ELECTRONICS ASIACENTRE PTE.LTD. 253 Alexandra Road, #04-01, Singapore 159936

C PIONEER CORPORATION 1999	K-ZZY. NOV. 1999 Printed in Japan

KEH-1900,1950

1. SAFETY INFORMATION

CAUTION

This service manual is intended for qualified service technicians; it is not meant for the casual do-it-yourselfer. 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

2. EXPLODED VIEWS AND PARTS LIST

2.1 PACKING

	1	16
6	3
7		17
		20
4

5
	9
2	12
10

14	18
	19

15

11

13

2

KEH-1900,1950

NOTE:

-Parts marked by “*” are generally unavailable because they are not in our Master Spare Parts List.

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

-PACKING SECTION PARTS LIST

				Part.No
Mark No. Description			KEH-1900/X1M/UC		KEH-1950/X1M/ES
*	1	Accessory Assy	CEA2350		CEA2350
	2	Spring	CBH1650		CBH1650
	3	Screw Assy	CEA2351		CEA2351
	4	Screw	CBA1304		CBA1304
*	5	Polyethylene Bag	CEG-127		CEG-127
	6	Screw	CRZ50P090FMC		CRZ50P090FMC
	7	Screw	TRZ50P080FMC		TRZ50P080FMC
*	8	Polyethylene Bag	CEG-158		CEG-158
	9	Handle	CNC5395		CNC5395
	10	Bush	CNV3930		CNV3930
	11	Polyethylene Bag	CEG1173		CEG-162
	12	Carton	CHG3913		CHG3914
	13	Contain Box	CHL3913		CHL3914
	14	Protector	CHP1622		CHP1622
	15	Protector	CHP1623		CHP1623
	16	Owner’s Manual	CRD3099		CRD3097
	17	Installation Manual	CRD3100		CRD3098
	18	Case Assy	CXB3520		CXB3520
	19	Cord Assy	CDE6145		CDE6145
*	20	Card	ARY1048		Not used

- Owner's Manual

Model	Part No.	Language
KEH-1900/X1M/UC	CRD3099	English, French, Spanish
KEH-1950/X1M/ES	CRD3097	English, Spanish, Portuguese(B), Chinese, Arabic

- Installation Manual

Model	Part No.	Language
KEH-1900/X1M/UC	CRD3100	English, French, Spanish
KEH-1950/X1M/ES	CRD3098	English, Spanish, Portuguese(B), Chinese, Arabic

3

KEH-1900,1950

2.2 EXTERIOR

4

KEH-1900,1950

(1) EXTERIOR SECTION PARTS LIST

Mark No. Description		Part No.		Mark No. Description			Part No.
1	Screw	BSZ26P050FMC			36	Button(TUNER/BAND)	CAC6297
2	Screw	BSZ30P055FUC			37	Button(1-6)	CAC6300
3	Screw	BSZ30P060FMC			38	Button(DETACH)	CAC6301
4	Screw	BSZ30P100FMC			39	Spring	CBH1836
5	Cord Assy	CDE6145			40	Spring	CBH2307
6	Case	CNB2481			41	Cover	CNS5696
7	Holder	CNC5704			42	Keyboard Unit	CWM6745
8	Insulator	CNM5025			43	LCD(LCD901)	CAW1568
9	Cushion	CNM5210			44	Connector(CN901)	CKS3580
10	Panel	CNS5214			45	Holder	CNC8525
11	Tuner Amp Unit	See Contrast table(2)			46	Sheet	CNM6486
12	Screw	BPZ26P080FMC			47	Lighting Conductor	CNV5969
13	Screw	BSZ26P080FMC			48	Rubber	CNV5970
14	Screw	BSZ26P140FMC			49	Connector	CNV5972
15	FM/AM Tuner Unit	See Contrast table(2)			50	Grille Unit	See Contrast table(2)
16	Holder	CNC6554			51	Button	CAC4836
17	Pin Jack(CN401)	CKB1028			52	Spring	CBH1834
18	Plug(CN603)	CKM1270			53	Spring	CBH1835
19	Connector(CN601)	CKS3362			54	Spring	CBH2367
20	Connector(CN602)	CKS3581			55	Bracket	CNC6135
21	Antenna Jack(CN301)	CKX1056			56	Bracket	CNC6791
22	Panel	CNB2247			57	Arm	CNV4692
23	Holder	CNC5399			58	Arm	CNV4693
24	Holder	CNC6216			59	Arm	CNV4728
25	Heat Sink	CNC6217			60	Panel Unit	CXB4926
26	Holder	CNC6531			61	Door	CAT2109
27	Holder	CNC6845			62	Spring	CBH1838
28	Chassis Unit	CXA9851			63	Screw	IMS20P030FZK
29	Holder Unit	CXB2687			64	Fuse(10A)	CEK1136
30	Detach Grille Assy	See Contrast table(2)			65	Cassette Mechanism Assy	EXK3410
31	Screw	BPZ20P120FZK			66	IC(IC501)	TDA7384
32	Button(EJECT)	CAC5870			67	Transistor(Q804)	2SD2395
33	Button(REW)	CAC5872	*		68 Cord		See Contrast table(2)
34	Button(FF)	CAC5874			69	Holder	See Contrast table(2)
35	Button(CROSS)	CAC6295

(2) CONTRAST TABLE

KEH-1900/X1M/UC and KEH-1950/X1M/ES are constructed the same except for the following:

			Part No.
Mark	No.	Description	KEH-1900/X1M/UC	KEH-1950/X1M/ES
	11	Tuner Amp Unit	CWM6742	CWM6744
	15	FM/AM Tuner Unit	CWE1467	CWE1486
	30	Detach Grille Assy	CXB4673	CXB4674
	50	Grille Unit	CXB4633	CXB4634
*	68	Cord	CDC1043	Not used
	69	Holder	CNC8818	Not used

5

KEH-1900,1950

2.3 CASSETTE MECHANISM ASSY

6

KEH-1900,1950

- CASSETTE MECHANISM ASSY SECTION PARTS LIST

Mark No. Description		Part No.		Mark No. Description		Part No.
1	Screw	BSZ23P050FMC	46		Gear	ENV1475
2	Washer	CBG1003	47		Gear	ENV1512
3	Connector(CN1)	CKS2829	48		Gear	ENV1513
4	Screw(M2x5)	EBA1038	49		Gear	ENV1502
5	Screw(M2x2.5)	EBA1037	50		Lever	ENV1480
6	Spring	EBH1554	51		Lever	ENV1487
7	Spring	EBH1555	52		•••••
8	Spring	EBH1556	53		Arm	ENV1519
9	Spring	EBH1603	* 54		PCB	ENP1161
10	Spring	EBH1591	55		•••••
11	Spring	EBH1559	56		Switch(FWD)(REV)(S3)	ESH1006
12	Spring	EBH1593	57		Switch(Load)(S1)	ESN1016
13	Spring	EBH1561	58		Switch(Mute)(S2)	ESN1017
14	Spring	EBH1562	59		Head Assy(HD1)	EXA1466
15	Spring	EBH1563	60		Motor Unit(M1)	EXA1467
16	Spring	EBH1623	61		Flywheel Unit	EXA1547
17	Spring	EBH1565	62		•••••
18	Spring	EBH1566	63		Arm Unit	EXA1447
19	Spring	EBH1567	64		Arm Unit	EXA1448
20	Spring	EBH1568	65		Arm Unit	EXA1534
21	Spring	EBH1569	66		Reel Unit	EXA1450
22	Spring	EBH1571	67		Pinch Holder	ENV1466
23	Spring	EBH1579	68		Pinch Roller	ENV1518
24	Head Base	ENC1475	69		Pinch Holder	ENV1467
25	Lever	ENC1429	70		•••••
26	Lever	ENC1430	71		Chassis Unit	EXA1498
27	Lever	ENC1431	72		Arm	ENV1524
28	Lever	ENC1432	73		Washer	HBF-167
29	Arm	ENC1433	74-78		•••••
30	Arm	ENC1434	79		Cover	ENC1452
31	Arm	ENC1480	80		Washer	CBF1051
32	Arm	ENC1493	81		Spring	EBH1592
33	Bracket	ENC1477
34	Lever	ENC1483
35	Arm	ENC1524
36	Frame	ENC1440
37	Holder	ENC1441
38	Lever	ENC1446
39	Lever	ENC1478
40	Belt	ENT1027
41	Gear	ENV1504
42	Gear	ENV1470
43	Gear	ENV1471
44	Lever	ENV1472
45	Gear	ENV1510

7

1		2		3		4

KEH-1900,1950

3. BLOCK DIAGRAM AND SCHEMATIC DIAGRAM

3.1 BLOCK DIAGRAM

A - KEH-1900/X1M/UC

A TUNER AMP UNIT

B FM/AM TUNER UNIT

TUN-L

ILL+B

Q3

T31

Q31

CF51

CF52

CF53

T51

CN301

FM RF

FM/AM MIX FM/AM IF

FM IF

FM IF

ANT

25

26

41

9

10

14

17

19

47

1

2

FWD-L

15

FWD

34

FM/AM PROCESSOR

FM PROCESSOR

FM

19

7

Lch

OSC

IC 1

PA4023B

IC 2 PA4024A

Q201 Q202

6

38

32

36

16

18

23

25

31

30

28

40

43

REV

Lch

B

AMRF/AGC

CF232 AM IF

FMSL

9

HEAD

REV-L

AMSL

FMTV

AMTV

AM

AMIFC

VCO

FMSD

18

FM+B

AM+B

TUN+B

OSC

19 20

15

17

21

14

13

6

M

Q804

Q802

B.U

D

FIX+B

MOTOR

SYSPW

9V REGULATOR

Q803

ILL+B

SL

14

SL

12

C KEYBO

FMSD

FMSD

C

SYSTEM CONTROLLER

AMIF

VCO

FIX+B

Q805

FIX+B

IC 601 (1/2)

IL901-903

Q806

PE5107A

Q302

Q303

EO

FM

AM

LOOP FILTER

Q808

Q807

FM SWITCH

AM SWITCH

EO

AMIF

VCOIN

FM

AM

XI

XO

KEY MATRIX

3

13

6

54

51

25

24

X601

4.5MHz

D

8

1

2

3

4

5

6

7

8

KEH-1900,1950

A

TUN-L

CN401

RL OUT

RL

REAR Lch OUT

ILL+B

Q403

Q401

MUTE

ELECTRONIC

9

FL+

FL+

FWD-L

VOLUME

POWER AMP

FL+

6

FL

CASSETTE

7

FWD/REV SWITCH

2

IC 401

19

11

FL

FL-

FL-

5

FL-

SPEAKER

EQUALIZER

3

15

IC 501

SN761029DL

20

17

1

IC 201

RL

RL+

RL+

1

1

3

TDA7384

RL+

8

RL

LA3161P

STBY

MUTE

RL-

19

RL-

9

RL-

SPEAKER

4

4

22

FIX+B

SYSPW

REV-L

B.U

FWD/REV

6

6

VDT/VCK/VST

B

MUTE SWITCH

4

4

Q810

Q609

Q501

8

8

MUTE

LOAD SWITCH

MECHA

MUTE

9

9

LOAD

POWER SWITCH

GND

Q607

Q502

10

10

B.U

FUSE

CN601

MECPW

10A

BATTERY

Q608

7

Q809

ACC

2

ACC

D CASSETTE PCB

DMINH

Q606

Q601

CE

B.U

VDD1

Q603

VDD2

VDD

MECHA MUTE

Q604

Q605

B.U

Q801

B REMOTE

EYBOARD UNIT

B.U

5

IC 801

1

BRE

1

B REMOTE

TPD1018F

CN901

CN602

C

6

CN603

SYSPW

ILL+B

03

4

4

3

3

SW5V

VDD

24

VDD

Q602

SYSPW

RES 17

KEY/LCD

SCK

SWVDD

DRIVER

SCK 15

5

5

SO 14

6

6

SIO

18

1

2

63

50

39

40

7

43

IC 901

SI

13

SWVDD

MCMUT

TAPLD

NOR/REV

MECPW

MUTE

DMINH

CE

SYSPW

PDC045A

MATRIX

9

LCK

10

LDT

SYSTEM CONTROLLER

LCD 901

CAW1568

IC 601 (2/2)

PE5107A

D

9

5

6

7

8

1		2		3		4

KEH-1900,1950

3.2 OVERALL CONNECTION DIAGRAM(GUIDE PAGE)

Note: When ordering service parts, be sure to refer to “EXPLODED VIEWS AND PARTS LIST” or “ELECTRICAL PARTS

LIST”.

A TUNER AMP UNIT

A

A-a

						Large size
						SCH diagram
	A-a			A-b

A-a	A-b	Guide page
A-a	A-b	Detailed page

ELECTRONIC VOLU

B FM/AM TUNER UNIT

AM : -26.0dBs

FM : -20.0dBs

-29.0d

ES ONLY

B

C

ES ONLY

***	***	***	UC ES R313 10K 22K C313 R022 R047 C314 R01 R001	ES ONLY
				UC ONLY
				SYSTEM CONTROLLER
				UC ONLY

EQ AMP

-73dBs

D

D

CASSETTE PCB

D

10

A

1

2

3

4

5		6		7		8

KEH-1900,1950

A-b

UME

dBs

FM : 100% 35.1dBs	A
AM : 30% 24.1dBs
TAPE : 315Hz 0dB 22.1dBs

TAPE : -4.5dBs

TAPE : -3.9dBs	POWER AMP
AM : -0.9dBs
FM : 5.1dBs

B

TAPE : 22.1dBs

FUSE

600 H

ES ONLY

B.REMOTE

C

KEY/LCD DRIVER

CEL 1547

14V 40mA

******

UC ES

C427 24P

C428 27P 24P

D

C KEYBOARD UNIT

A C 11

5		6		7		8

1

KEH-1900,1950

		A-b
	A	-a
		A
		ELECTRONIC VOLUME
	B

C	UNITAMP	UNITTUNERFM/AM
	TUNER	B
D	A

12 A-a

2 3 4

1

2

-29.0dBs

-26.0dBs	-20.0dBs
AM :	FM :

ES ONLY

ES ONLY

ESONLY

UC ONLY

R01R001		C314
C313R022R047
22K	10K	R313
ES	UC
***
***
***

1

2

3

4

5		6		7		8

KEH-1900,1950

SYSTEM CONTROLLER

3	4
		ES	24P	24P
	***	UC	C427	C428 27P	a A-b
					A-

EQ AMP

UCONLY

A

B

C

UC ONLY -73dBs

D CASSETTE PCB

A-a D 13

D

5		6		7		8