Pioneer KEH-P4800 User manual

PIONEER ELECTRONIC 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. 501 Orchard Road, #10-00, Wheelock Place, Singapore 238880
C PIONEER ELECTRONIC CORPORATION 1998 K-ZZU. OCT. 1998 Printed in Japan
ORDER NO.
CRT2261
MULTI-CD CONTROL HIGH POWER CASSETTE PLAYER WITH FM/AM TUNER
KEH-P4800 X1M/UC
Service
Manual
CONTENTS
1. SAFETY INFORMATION............................................2
2. EXPLODED VIEWS AND PARTS LIST ......................2
3. SCHEMATIC DIAGRAM.............................................8
4. PCB CONNECTION DIAGRAM................................22
5. ELECTRICAL PARTS LIST........................................32
6. ADJUSTMENT.........................................................39
7. GENERAL INFORMATION.......................................41
7.1 PARTS ................................................................41
7.1.1 IC...............................................................41
7.1.2 DISPLAY ...................................................45
7.2DISASSEMBLY ...................................................46
7.3BLOCK DIAGRAM ..............................................47
8. OPERATIONS AND SPECIFICATIONS....................48
NOTE:
-See the separate manual CX-631(CRT1640) for the cassette mechanism description.
-The cassette mechanism assy employed in this model is one of 2L series.
-This service manual does not describe the CD test mode.
For the operations in the CD test mode, refer to the CD player's Service Manual.
KEH-P4850 X1M/ES
KEH-P4850/X1M/ES

4
KEH-P4800,P4850
2.2 EXTERIOR

5
KEH-P4800,P4850
1 Screw BSZ26P050FMC
2 Screw BSZ30P050FMC
3 Cord Assy CDE5798
4 Fuse(10A) CEK1136
5 Case CNB2350
6 Panel CNS5132
7 Screw BSZ30P050FMC
8 Screw BSZ30P200FMC
9 Holder CNC5704
10 Cushion CNM5210
11 Insulator CNM5963
12 Tuner Amp Unit See Contrast table(2)
13 Screw BPZ26P080FMC
14 Screw BSZ26P080FMC
15 Screw BSZ26P160FMC
16 FM/AM Tuner Unit See Contrast table(2)
17 Holder CNC6554
18 Pin Jack(CN301) CKB1035
19 Plug(CN603) CKM1270
20 Connector(CN701) CKS3408
21 Connector(CN602) CKS3568
22 Connector(CN601) CKS3581
23 Antenna Jack(CN402) CKX1056
24 Panel CNB2343
25 Holder CNC5399
26 Holder CNC6845
27 Holder CNC7996
28 Heat Sink CNR1505
29 Chassis Unit CXB3012
30 Screw ISS26P055FUC
31 Holder Unit CXB2687
32 Detach Grille Assy See Contrast table(2)
33 Screw BPZ20P060FMC
34 Screw BPZ20P100FZK
35 Button(Detach) CAC5789
36 Button(1-6) CAC5794
37 Button(-) CAC5930
38 Button(EQ) CAC6135
39 Button(+) CAC5783
40 Button(Eject) CAC5793
41 Button(Display) CAC5788
42 Button(Cross) CAC5786
43 Button(A,B) CAC5787
44 Spring CBH2103
45 Cover CNS5130
46 Housing CNV5528
47 Keyboard Unit See Contrast table(2)
48 LCD(LCD1901) CAW1543
49 Connector(CN1901) CKS3580
50 Holder CNC7981
51 Sheet CNM5941
52 Lighting Conductor CNV5527
53 Connector CNV5531
54 Grille Unit See Contrast table(2)
55 Button CAC4836
56 Spring CBH1834
57 Spring CBH1835
58 Spring CBH2182
59 Bracket CNC6135
60 Bracket CNC6791
61 Arm CNV4692
62 Arm CNV4693
63 Arm CNV4728
64 Panel Unit CXB3019
65 Door CAT2028
66 Spring CBH1838
67 Screw IMS20P030FZK
68 Case Assy CXB3520
69 Cassette Mechanism ModuleEXK3695
70 IC(IC302) TDA7384
71 Transistor(Q904) 2SD2396
(1) EXTERIOR SECTION PARTS LIST
Mark No. Description Part No. Mark No. Description Part No.

6
KEH-P4800,P4850
2.3 CASSETTE MECHANISM MODULE
(2)CONTRAST TABLE
KEH-P4800/X1M/UC and KEH-P4850/X1M/ES have
the same construction except for the following:
Part No.
Mark No. Description KEH-P4800/X1M/UC KEH-P4850/X1M/ES
12 Tuner Amp Unit CWM6248 CWM6249
16 FM/AM Tuner Unit CWE1467 CWE1486
32 Detach Grille Assy CXB3322 CXB3323
47 Keyboard Unit CWM6259 CWM6260
54 Grille Unit CXB4065 CXB4066

7
KEH-P4800,P4850
Mark No. Description Part No. Mark No. Description Part No.
1 Screw BSZ20P040FMC
2 Washer CBF1037
3 Washer CBF1038
4 Washer CBG1003
5 Deck Unit EWM1021
6 Screw EBA1028
7 Screw EBA1037
8 Spring EBH1531
9 Spring EBH1575
10 Plug(CN251) CKS3540
11 Spring EBH1515
12 Spring EBH1587
13 Spring EBH1517
14 Spring EBH1518
15 •••••
16 Spring EBH1537
17 Cord EDD1020
18 Photo-interrupter(EGN2,3) EGN1006
19 Photo-interrupter(EGN1) EGN1005
20 Roller ENR1031
21 Shaft ELA1373
22 Pinch Roller ENV1518
23 Arm ENC1489
24 Arm ENC1397
25 Guide ENC1481
26 Holder ENC1417
27 Lever ENC1448
28 Arm ENC1488
* 29 Motor EXM1031
30 Belt ENT1027
31 Gear ENV1347
32 Collar ENV1508
33 Gear ENV1350
34 Flywheel ENV1500
35 Worm Gear ENV1439
36 Worm Wheel ENV1440
37 Gear ENR1028
38 Lever ENV1442
39 •••••
40 Gathering PCB ENX1037
41 Gathering PCB ENX1042
42 Switch(S1) ESG1004
43 Motor Unit(M2) EXA1485
44 Chassis Unit EXA1511
45 Pinch Holder ENV1485
46 Pinch Holder ENV1486
47 Reel Unit EXA1543
48 Head Base Unit EXA1457
49 Lever Unit EXA1438
50 Gear Unit EXA1574
51 Frame Unit EXA1458
52 Lever Unit EXA1439
53 Head Assy(HD1) EXA1506
54 Motor Unit(M1) EXA1490
55 Washer HBF-179
56 Screw BMZ20P022FMC
57 Spring EBH1545
58 Washer YE20FUC
59 Pinch Holder Unit EXA1529
60 Pinch Holder Unit EXA1528
-CASSETTE MECHANISM MODULE SECTION PARTS LIST

8
KEH-P4800,P4850
A
1234
B
C
D
1234
3. SCHEMATIC DIAGRAM
3.1 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-a A-b
A-a A-b
A-b
A-a
Large size
SCH diagram
Guide page
Detailed page
4R7/16
UC model
ES model
331:UC model 510:ES model
FM/AM TUNER UNIT
TAPE: -9dBs
FM: -15.5dBs
AM: -22dBs
For resistors and capacitors in the circuit diagrams, their resistance values or
capacitance values are expressed in codes:
Ex. *Resistors
Code Practical value
123 12k ohms
103 10k ohms
*Capacitors
Code Practical value
103 10kpF(0.01uF)
101/10 100uF/10V
B
D
KEYBOARD UNIT
C
DECK UNIT
A-a
A

9
KEH-P4800,P4850
5678
A
B
C
D
5678
102:UC
103:ES
PD4973A
TUNER AMP UNIT
CD: +2.2dBs
FM: +9.6dBs
AM: -3.1dBs
TAPE: -4dBs
CD: +10.3dBs
FM: +35.6dBs
AM: +29.1dBs
TAPE: +22.0dBs
CD: +36.3dBs
SYSTEM CONTROLLER
IP-BUS DRIVER
ELECTRONIC VOLUME
POWER AMP
RESET
8V REGULATER
A
IP-BUS
CEK1136
TAPE: -4.2dBs
CN1901
T
332/16
A
A-b

10
KEH-P4800,P4850
A
1234
B
C
D
1234
4R7/16
UC model
ES model
331:UC model
510:ES model
102:U 103:E
FM/AM TUNER UNIT
FM: -15.5dBs AM: -22dBs
B
A-a
A-a A-b

11
KEH-P4800,P4850
5678
A
B
C
D
5678
TAPE: -9dBs
SYSTEM
For resistors and capacitors in the circuit diagrams, their resistance values or capacitance values are expressed in codes: Ex. *Resistors Code Practical value 123 12k ohms 103 10k ohms *Capacitors Code Practical value 103 10kpF(0.01uF) 101/10 100uF/10V
D
CN1901
KEYBOARD UNIT
C
DECK UNIT
A-a
A-a A-b

12
KEH-P4800,P4850
A
1234
B
C
D
1234
TUNER AMP UNIT
FM: +9.6dBs AM: -3.1dBs TAPE: -4dBs CD: +10.3dBs
FM: +35.6dBs AM: +29.1dBs TAPE: +22.0dBs CD: +36.3dBs
IP-BUS DRIVER
ELECTRONIC VOLUME
POWER AMP
RESET
8V REGULATER
A
CEK1136
TAPE: -4.2dBs
332/16
A-a A-b
A-b

13
KEH-P4800,P4850
5678
A
B
C
D
5678
PD4973A
CD: +2.2dBs
CONTROLLER
8V REGULATER
IP-BUS
A-b
A-a A-b

14
KEH-P4800,P4850
A
1234
B
C
D
1234
3.2 FM/AM TUNER UNIT
-KEH-P48000/X1M/UC
B
3
1
2
FM/AM TUNER U
D1D2 RD39JSRD39JS
R1
R2
2R2M
2R2M
D6 MA157
B

15
KEH-P4800,P4850
5678
A
B
C
D
5678
B
ER UNIT
IFC
A

3
1
2
FM/AM TUNER U
D1D2 RD39JSRD39JS
R1
R2
2R2M
2R2M
D6 MA157
16
KEH-P4800,P4850
A
1234
B
C
D
1234
-KEH-P4850/X1M/ES
B
B

ER UNIT
IFC
17
KEH-P4800,P4850
5678
A
B
C
D
5678
B
A

18
KEH-P4800,P4850
A
1234
B
C
D
1234
CAW1543
3.3 KEYBOARD UNIT
C

19
KEH-P4800,P4850
5678
A
B
C
D
5678
CKEYBOARD UNIT
43
IL1901-1905:CEL1605
40mA 14V
EDIT
CLOCK
PTY
PAUSE/BSM
C
CN601
A

20
KEH-P4800,P4850
A
1234
B
C
D
1234
3.4 CASSETTE MECHANISM MODULE
D
DECK UNIT
MUTE
CXA2559Q
11
12
13
14
15
16
17
18
19
20
40
39
38
37
36
35
34
33
32
31
30
29 28 27
26 25
24
23
22 21
1
2 3 4
5 6
7
8
9 10
CN602
R256 220
R287
0R0
C273
22/16
R283 0R0
R284 0R0
R282 0R0
C253 330P
C254 330P
C252 330P
C251 330P
R281 0R0
R255 220
C256
R01
R258
1K
R301
18K
R273 1K
R274 1K
R271 1K
R272 1K R290 0R0
C403 R068
R403 82K
C402
4700P
C401
R33
R40216K
R401
4R7K
R323 0R0
R257
1K
C255
R01
C272 R1
C313 100P
R386 0R0
R285 0R0
HD1
HEAD ASSY
EXA1506
TEST TAPE
NCT-150
(400Hz, 200nWb/m)
RL
RR
FR
FL
Signal GND
C302
R1
C302
R1
C301
R1
R304R302 16K16K
R305
16K
R303
16K
-6dBs(388mV)±1dB A
D

21
KEH-P4800,P4850
5678
A
B
C
D
5678
F
E
D
PCB UNIT
REEL PCB
SWITCHES:
PCB UNIT
S1:LOAD SWITCH..........EJECT-PLAY
S2:70µs SWITCH............ON-OFF
The underlined indicates the switch position.
0R0
R068
3 82K
R40216K
R401
4R7K
R351 1K
R352 1K
R353 1K
R354 1K
R373 0R0
R355 270K
C352 3900P
R362 180
C351 R22
C353 R01
C354 R01
R374 0R0
C356 R01
C355 R1
D352 1SS355
M1
MOTOR UNIT
(MAIN MOTOR)
EXA1490
S1 LOAD
ESG1004 S2
ESG1004
70µs
MODE
SENSE
EGN1
EGN1005
EGN2
EGN1006
FWD END
SENSE
EGN3
EGN1006
REV END
SENSE
M2
MOTOR UNIT
(SUB MOTOR)
EXA1485
Power GND
E
F

31
KEH-P4800,P4850
1234
A
B
C
D
1234
Fig. 20
F
E
E
PCB UNIT
REEL PCB
SIDE A
SIDE B
E
F
LOAD SW
S1
70µSW
S2
MODE SENSE
EGN1
1
4
7
123456
E
PCB UNIT
D
CN253
F