XR-4950X

SERVICE MANUAL

AEP Model

Ver 1.0 2001.04

Model Name Using Similar Mechanism

NEW

Tape Transport Mechanism Type

MG-25F-136

SPECIFICATIONS

Cassette player section

General

Tape track

4-track 2-channel stereo

Outputs

Audio output

Wow and flutter

0.08 % (WRMS)

Power aerial relay control

Frequency response

30 – 18,000 Hz

lead

Signal-to-noise ratio

58 dB

Power amplifier control

lead

Telephone ATT control

lead

Tuner section

Tone controls

Bass �ą9 dB at 100 Hz

FM

Treble �ą9 dB at 10 kHz

Tuning range

87.5 – 108.0 MHz

Power requirements

12 V DC car battery

Aerial terminal

External aerial connector

(negative earth)

Intermediate frequency

10.7 MHz/450kHz

Dimensions

Approx. 178 � 50 � 183 mm

Usable sensitivity

8 dBf

(w/h/d)

Selectivity

75 dB at 400 kHz

Mounting dimensions

Approx. 182 � 53 � 162 mm

Signal-to-noise ratio

66 dB (stereo),

(w/h/d)

72 dB (mono)

Mass

Approx. 1.2 kg

Harmonic distortion at 1 kHz

Supplied accessories

Parts for installation and

0.6 % (stereo),

connections (1 set)

0.3 % (mono)

Front panel case (1)

Separation

35 dB at 1 kHz

Frequency response

30 – 15,000 Hz

Design and specifications are subject to change without notice.

AM

Tuning range

531 – 1,602 kHz

Aerial terminal

External aerial connector

Intermediate frequency

10.7 MHz/450 kHz

Sensitivity

30 µV

Power amplifier section



Outputs

Speaker outputs

(sure seal connectors)

Speaker impedance

4 – 8 ohms

Maximum power output 50 W � 4 (at 4 ohms) FM/AM CASSETTE CAR STEREO

9-873-510-11

Sony Corporation

2001D0500-1

e Vehicle Company

C 2001.4

Shinagawa Tec Service Manual Production Group





XR-4950X

6-3.

SCHEMATIC DIAGRAM – MAIN Board (1/2) –

�ó See page 15 for Waveforms.

�ó See page 21 for IC Block Diagrams.

(Page 19)

18

18





XR-4950X

6-4.

SCHEMATIC DIAGRAM – MAIN Board (2/2) –

�ó See page 21 for IC Block Diagrams.

(Page

(Page 18)

20)

19

19





XR-4950X

6-5.

PRINTED WIRING BOARD – SUB Board –

6-6.

SCHEMATIC DIAGRAM – SUB Board –

LED801

K

K

K1 S2 K2

A

A

A1 S1 A2

LSW801

K1

S2

K2

(Page 23)

A1

S1

A2

(Page 19)

(Page 17)

(Page 22)

20

20





XR-4950X

�ó IC Block Diagrams

– MAIN Board –

IC331

TDA7402TR

IC301

CXA2509AQ-T4

IC351

LB1930M-TLM

VCC 1

10 NC

ACINLR

ACINRF

ACINRR

OUTLF

OUTLR

OUTRF

OUTRR

OUTSWL

OUTSWR

OUTSSL

OUTSSR

BUFFER

PBEQ2

PBOUT2

GND

TAPEIN2

AUXIN2

DIREF

LINEOUT2

NC

NC

MSSW

NC 2

33 32 31

30

29

28

27

26

25

24 23

30

29

28 27

26

25

24

23 22 21

IN1 3

9 OUT1

MOTOR

CONTROL

DRIVE

8

NC

MIXER

CIRCUIT

24dB

IN2 4

CIRCUIT

7 OUT2

120µ/70µ

BUFFER

MONO- MONO-

MONO- MONO-

MONO- MONO-

T2

+ –

S-GND 5

6 P-GND

FADER

FADER

FADER

FADER

FADER

FADER

20 MSMODE

–

+

ACINLF 34

NR BIAS

FRONT

MS

SUBWOOFER

PBFB2 31

19 DRSW

X1

SWINR 35

ACIN

MODE

+PHASE

PBRIN2 32

SWINL 36

OUTPUT

TAPE/AUX

REAR

CONTROL

SELECTOR

18 TAPESW

PBREF2 33

F2

17 INSW

ACOUTR 37

TAPE EQ

MAIN

SW

PBFIN2 34

ACOUTL 38

SECOND

16 NC

FWD/RVS

CREF 39

VCT 35

VCT

PBGND 36

VCC

15 NC

MS ON/

OFF

22 VDD

+

LPF

+

LP

DETECT

–

VOICE

21 SCL

BANDPASS

PBFIN1 37

14 MSOUT

20

HP

SDA

IIC-BUS

F3

PBREF1 38

F1

X1

13 DGND

PBRIN1 39

BASS

PBFB1 40

12 MSTC

–

+

SUPPLY

19 GND

+

–

11 G1FB

TREBLE

T1

HIGH-CUT

18 SM

120µ/70µ

24dB

VOLUME

S&H

PULSE

FORMER

1

2

3

4

5

6

7

8

9

10

SOFTMUTE

NC

NC

VCC

25kHz

QUAL

17 QUAL

G2FB

PBEQ1

COMPANDER

LP

PBOUT1

DIGITAL CONTROL

TAPEIN1

AUXIN1

MSLPF

LINEOUT1

LOUDNESS

LOUDNESS

16

MULTIPATH

MPOUT

DEMODULATOR

MUX 40

DETECTOR

15 MPIN

IN-GAIN

+STEREO ADJUST

+

+STEREO BLAND

BEEP

D/A

14

IN-GAIN

MUTE

LEVEL

CONVERTER

PILOT

+AUTO ZERO

IC611

BA4908-V3

CANCELATION

PIL DET

MAIN SOURCE

MIXING

SECOND SOURCE

SELECTOR

SELECTOR

SELECTOR

PLL

MD1 41

MAIN

MD1G 42

80kHz

INPUT

13 MPX

REGULATOR

LP

MULTIPLEXER

FM

MD2 43

PHONO

MD2G 44

AM/FM

MAIN

CH0

AUX

AM

12 AMIF

NOISE BLANKER

1 2

3 4 5 6

7 8 9 10

11

OVER VOLTAGE

PROTECT

SEL

SER

AM

FD1L+

FD1L–

FD1R+

FD1R–

FD2L+

FD2L–

FD2R+

FD2R–

–

–

–

–

+

+

+

+

1

2 3 4

5

6

7

8

9

10

11

12

NC

STB

AMP

VCC

ANT

GND

VDD5.6V

COM8.7V

TUNER5.6V

TUNER8.7V

TUNER5.6 SW

TUNER8.7 ANT SW

21

21





XR-4950X

6-8.

SCHEMATIC DIAGRAM – KEY Board –

�ó See page 15 for Waveform.

(Page

20)

23

23





XR-4950X

6-9.

IC PIN FUNCTION DESCRIPTION

�ó MAIN BOARD IC501 MN101C49KTA2 (SYSTEM CONTROLLER) Pin No.

Pin Name

I/O

Description

Pin No.

Pin Name

I/O

Description

1

VREF

I

Reference voltage (0V) input terminal (for A/D converter) 38

ACC IN

I

Accessory detection signal input �śL”: accessory on FM and AM signal meter voltage detection input from the FM/AM tuner unit (TU1) 39

TESTIN

I

Setting terminal for the test mode �śH”: test mode, Normally: fixed at �śL”

2

VSM

I

(A/D input)

40

TELATT

I

Telephone muting signal input terminal At input of �śH”, the signal is attenuated by –20 dB

3

FMAGC

I

FM AGC level detection signal input from the FM/AM tuner unit (TU1) (A/D input) 41

UNICLI

I

Serial data transfer clock signal input terminal Not used (fixed at �śL”) Key input terminal (A/D input) (LSW801, LSW909, LSW912 to LSW917) 4

KEYIN1

I

42

UNISO

O

Serial data output terminal Not used (fixed at �śL”) Z, D-BASS, 6, 5, 4, 3, 2, REP 1 keys input 43

UNISI

I

Serial data input terminal Not used (fixed at �śL”) Key input terminal (A/D input) (LSW901 to LSW907, S901 to S904) 44

UNICKO

O

Serial data transfer clock signal output terminal Not used (fixed at �śL”) 5

KEYIN0

I

OFF, SOURCE, SOUND, MENU, MODE o, ENTER, SEEK/AMS – . m,PRST +, SEEK/AMS + > M, PRST – keys input

45

I2C SIO

I/O

Two-way data bus with the electrical volume (IC331) and FM/AM tuner unit (TU1) 6

DSTSEL

I

Destination setting terminal (fixed at �śH” in this set) 46

VOLATT

O

Muting on/off control signal output to the electrical volume (IC331) �śL”: muting on 7

RCIN0

I

Rotary remote commander key input terminal (A/D input) 47

I2C CKO

O

Clock signal output to the electrical volume (IC331) and FM/AM tuner unit (TU1) 8

QUALITY

I

Noise level detection signal input at SEEK mode (A/D input) Not used (open) Standby on/off control signal output to the power amplifier (IC751) 48

AMPON

O

�śL”: standby mode, �śH”: amplifier on

9

�"

O

Not used (open)

49

AMPATT

O

Muting on/off control signal output to the power amplifier (IC751) �śL”: muting on 10

VREF

I

Reference voltage (+5V) input terminal (for A/D converter) 50

ATT

O

Audio line muting on/off control signal output �śH”: muting on 11

VDD

�"

Power supply terminal (+5V) (for A/D converter) Muting on/off control signal output of the FM and AM tuner signal �śH”: muting on 12

OSCOUT

O

Main system clock output terminal (18.432 MHz) 51

TU ATT

O

Not used (open)

13

OSCIN

I

Main system clock input terminal (18.432 MHz) Tape auto music sensor control signal output to the CXA2509AQ (IC301) 14

VSS

�"

Ground terminal (for A/D converter)

52

AMSON

O

�śL” is output to lower the gain for audio level at FF/REW mode 15

XIN

I

Sub system clock input terminal (32.768 kHz) Forward/reverse direction control signal output to the CXA2509AQ (IC301) 16

XOUT

O

Sub system clock output terminal (32.768 kHz) 53

NROUT

O

�śL”: forward direction, �śH”: reverse direction 17

MMOD

I

Not used (fixed at �śL”)

METAL control in/out terminal

Front panel block remove/attach detection signal input At initial mode: auto/manual mode selection input of METAL function (manual at �śL” input) 18

NOSESW

I

54

MTLON

I/O

�śL”: front panel is attached, �śH”: front panel is removed At manual mode: METAL on/off control signal output terminal (METAL on at �śH” output) At auto mode: input at MTLIN (pin es)

19

BUSON

O

Bus on/off control signal output terminal �śL”: bus on Not used (fixed at �śH”) Tape muting on/off control signal output to the CXA2509AQ (IC301) �śH”: muting on 20

SYSRST

O

Reset signal output terminal �śL”: reset Not used (fixed at �śH”) 55

TAPATT

O

Active at ATA, FF/REW mode

21

LCDSO

O

Serial data output to the liquid crystal display driver (IC901) Dolby control in/out terminal

22

LCDCE

O

Chip enable signal output to the liquid crystal display driver (IC901) �śH” active At initial mode: valid/invalid selection input of dolby function (valid at �śL” input) 56

DOLON

I/O

23

LCDCKO

O

Serial data transfer clock signal output to the liquid crystal display driver (IC901) At normal mode: dolby on/off control signal output terminal (dolby on at �śH” output) 24

RCIN1

I

Rotary remote commander shift key input terminal �śL”: shift Not used this function (fixed at �śH”)

Internal RAM reset detection signal input terminal Whether a music is present or not from CXA2509AQ (IC301) is detected at auto music sensor 57

AMSIN

I

25

RAMBU

I

Input terminal to check that RAM data are not destroyed due to low voltage

�śL”: music is present, �śH”: music is not present This checking is made within 50 msec after reset Not used (fixed at �śL”) 58

4VPRE

I

4VPREOUT model setting terminal �śL”: 4VPREOUT model Fixed at �śH” in this set Input of acknowledge signal for the key entry Acknowledge signal is input to accept function 59 to 73

�"

O

Not used (open)

26

KEYACK

I

and eject keys in the power off status On at input of �śH”

74

E2P SIO

I/O

Two-way data bus with the FM/AM tuner unit (TU1) 27

�"

O

Not used (open)

75

E2P CKO

O

Clock signal output to the FM/AM tuner unit (TU1) 28

BUIN

I

Battery detect signal input from the battery detect circuit �śL” is input at low voltage 76

�"

O

Not used (open)

29

SIRCS

I

Sircs remote control signal input terminal Not used (fixed at �śL”) 77

SWSHIFT

O

AM filter control signal output to the FM/AM tuner unit (TU1) �śL”: SW mode 30, 31

�"

O

Not used (open)

78

DOORSW

I

Front panel open/close detection signal input �śL” is input when the front panel is closed 32

MTLIN

I

Auto metal detection signal input terminal �śH”: auto metal Not used (fixed at �śL”) LED drive signal output of the tape window and Z indicator (LED801, LSW801) 79

DOORIND

O

System reset signal input from the reset signal generator (IC551) and reset switch (S551)

�śH”: LED on �śH” is output to turn on LED when front panel is opened 33

RESET

I

�śL”: reset �śL” is input for several 100 msec after power on, then it changes to �śH”

80

REIN1

I

Dial pulse input of the rotary encoder (RE901) (for volume control) Tuner system power supply on/off control signal output to the BA4908 (IC611) 34

TUNON

O

81

REIN0

I

�śH”: tuner power on

A/D converter power control signal output 35

BEEP

O

Beep sound drive signal output to the power amplifier (IC751) 82

AD ON

O

When the KEYACK (pin wh) that controls reference voltage power for key A/D conversion input Main system power supply on/off control signal output to the BA4908 (IC611) is active, �śL” is output from this terminal to enable the input 36

PW ON

O

�śH”: power on

Power on/off control signal output of the illumination LED and liquid crystal display driver 83

ILLON

O

37

COLSEL

I

Setting terminal for the illumination color �śL”: amber, �śH”: green Fixed at �śL” in this set (IC901) �śH”: power on

24

24

XR-4950X

Pin No.

Pin Name

I/O

Description

Rotation detection signal input from supply reel sensor and take-up reel sensor on the deck 84

REL

I

mechanism

85

POS3

I

Tape position (EJECT/FF/REW/

POS0: �śL”: EJECT mode, �śH”: others mode

86

POS2

I

REV/FWD mode) detection signal

POS1: �śL”: FF and FWD mode, �śH”: others mode 87

POS0

I

input from the tape operation switch

POS2: �śL”: REW mode, �śH”: others mode

on the deck mechanism

POS3: �śL”: REV and EJECT mode, �śH”: others mode 88

POS1

I

Motor drive signal output to the loading/tape operation motor driver (IC351) �śH” active 89

LMLOD

O

(For the loading direction and forward side operation) *1

Motor drive signal output to the loading/tape operation motor driver (IC351) �śH” active 90

LMEJ

O

(For the eject direction and reverse side operation) *1

91

TAPON

O

Tape system power supply on/off control signal output �śH”: tape on 92

CMON

O

Capstan/reel motor (M901) drive signal output �śH”: motor on 93, 94

�"

O

Not used (open)

95

DAVSS

�"

Ground terminal (for D/A converter) Not used (open) 96

NS MASK

O

Discharge control signal output terminal �śH”: discharge Not used (open) 97 to 99

�"

O

Not used (open)

100

DAVDD

�"

Power supply terminal (+5V) (for D/A converter) Not used (open)

*1 Loading/tape operation motor control

Mode

LOADING/

EJECT/

STOP

BRAKE

Terminal

FORWARD

REVERSE

LMLOD (pin il)

�śL”

�śH”

�śL”

�śH”

LMEJ (pin o;)

�śL”

�śL”

�śH”

�śH”

25





Document Outline


Front Page Front Page





Operating Instructions Location of controls

Installation

Connections





Disassembly Disassembly flow

Sub panel assy

Mechanism deck

Main board

Heat sink (2P)





Assembly Assembly flow

Housing

Arm (suction)

Lever (LDG-A)/(LDG-B)

GEAR (LDG-FT)

Guide (C)

Mounting position of capstan/reel motor (M901)





Adjustment - general Mechanical adjustments

Tape deck section





Waveforms Waveforms





MCB Layouts Main board

SUB board

KEY board





Circuit Diagrams Main board (1/2)

Main board (2/2)

SUB board

KEY board





Semiconductor Block Diagrams IC block diagrams





Semiconductor Pin Layouts IC pin function description - main board IC501





Exploded Views General section

Front panel section

Mechanism deck section





Service Notes Parts for installation and connections