Sony CDXC-7850-R Service manual

CDX-C7850R

SERVICE MANUAL

SPECIFICATIONS

AEP Model

UK Model

Model Name Using Similar Mechanism CDX-C780R CD Drive Mechanism Type MG-363S-121 Optical Pick-up Name KSS-521A

CD player section

System Compact disc digital audio

system Signal-to-noise ratio 99 dB Frequency response 10 - 20,000 Hz Wow and flutter Below measurable limit

Tuner section

Tuning range 87.5 - 108.0 MHz Aerial terminal External aerial connector Intermediate frequency 10.7 MHz Usable sensitivity 8 dBf Selectivity 75 dB at 400 kHz

50 dB at 200 kHz Signal-to-noise ratio 65 dB (stereo),

68 dB (mono) Harmonic distortion at 1 kHz

0.7% (stereo),

0.4% (mono) Separation 35 dB at 1 kHz Frequency response 30 - 15,000 Hz

MW/LW

Tuning range MW : 531 - 1,602 kHz

LW : 153 - 281 kHz Aerial terminal External aerial connector Intermediate frequency 10.71 MHz / 450 kHz Sensitivity MW : 30 µV

LW : 50 µV

Power amplifier section

Outputs Speaker outputs

(sure seal connectors)

Speaker impedance 4 - 8 ohms Maximum power output 45 W × 4 (at 4 ohms)

General

Outputs Line outputs (3)

Power aerial relay control lead Power amplifier control lead Telephone ATT control lead Illumination control lead

T one controls Bass ±8 dB at 100 Hz

Treble ±8 dB at 10 kHz

Power requirements 12 V DC car battery

(negative ground)

Dimensions Approx. 178 × 50 × 182 mm

(w/h/d)

Mounting dimension Approx. 182 × 53 × 163 mm

(w/h/d) Mass Approx. 1.4 kg Supplied accessories Rotary commander (RM-X4S) (1)

Parts for installation and

connections (1 set)

Front panel case (1)

Design and specifications are subject to change without notice.

MICROFILM

FM/MW/LW COMPACT DISC PLAYER

– 1 –

SERVICE NOTE

TABLE OF CONTENTS

CAUTION

Use of controls or adjustments or performance of procedures other than those specified herein may result in hazardous radiation exposure.

Notes on Chip Component Replacement

• Never reuse a disconnected chip component.

• Notice that the minus side of a tantalum capacitor may be dam-

aged by heat.

NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK OR BASE UNIT

The laser diode in the optical pick-up block may suffer electrostatic breakdown because of the potential difference generated by the charged electrostatic load, etc. on clothing and the human body. During repair, pay attention to electrostatic breakdown and also use the procedure in the printed matter which is included in the repair parts. The flexible board is easily damaged and should be handled with care.

NOTES ON LASER DIODE EMISSION CHECK

The laser beam on this model is concentrated so as to be focused on the disc reflective surface by the objective lens in the optical pickup block. Therefore, when checking the laser diode emission, observe from more than 30 cm away from the objective lens.

NOTES ON PICK-UP FLEXIBLE BOARD

The pick-up flexible board in this set is secured to the optical pickup with an adhesive tape. Once the tape is removed, an adhering force becomes weak, and it cannot be reused. Therefore, if the optical pick-up is replaced, replace also the pickup flexible board with a new one.

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY MARK ! OR DOTTED LINE WITH MARK ! ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE P ART NUMBERS APPEAR AS SHOWN IN THIS MANU AL OR IN SUPPLEMENTS PUBLISHED BY SONY.

1. GENERAL

Location of controls................................................................. 3

Getting Started......................................................................... 3

CD Player ................................................................................ 4

Radio ....................................................................................... 5

RDS ......................................................................................... 5

Setting the clock automatically ............................................... 7

Other Functions ....................................................................... 7

CD/MD Unit............................................................................ 8

Connections ........................................................................... 10

2. DISASSEMBLY

2-1. Cover ................................................................................. 13

2-2. Front Panel Assy ............................................................... 13

2-3. Sub Panel Assy.................................................................. 14

2-4. Mechanism Block ............................................................. 14

2-5. Main Board ....................................................................... 15

2-6. Heat Sink ........................................................................... 15

2-7. Chassis (T) Sub Assy ........................................................16

2-8. Lever Assy ......................................................................... 16

2-9. Servo Board....................................................................... 17

2-10. Roller Assy........................................................................ 17

2-11. Chassis (OP) (O/S) Assy ................................................... 18

2-12. Optical Pick-up Block ....................................................... 18

3. ELECTRICAL ADJUSTMENTS

Tuner Section.........................................................................19

4. DIAGRAMS

4-1. IC Pin Descriptions ...........................................................23

4-2. Block Diagram –CD Section–........................................... 31

4-3. Block Diagram –Display Section–.................................... 33

4-4. Block Diagram –Tuner Section–....................................... 35

4-5. Circuit Boards Location .................................................... 37

4-6. Schematic Diagram –CD Mechanism Section (1/3)– ....... 39

4-7. Schematic Diagram –CD Mechanism Section (2/3)– ....... 41

4-8. Schematic Diagram –CD Mechanism Section (3/3)– ....... 43

4-9. Printed Wiring Boards –CD Mechanism Section–............ 46

4-10. Printed Wiring Board –Main Section– .............................. 49

4-11. Schematic Diagram –Main Section (1/4)– ........................ 53

4-12. Schematic Diagram –Main Section (2/4)– ........................ 55

4-13. Schematic Diagram –Main Section (3/4)– ........................ 57

4-14. Schematic Diagram –Main Section (4/4)– ........................ 59

4-15. Printed Wiring Board –Display Section– .......................... 61

4-16. Schematic Diagram –Display Section–............................. 63

4-17. Printed Wiring Board –Relay Section– ............................. 65

4-18. Schematic Diagram –Relay Section–................................ 67

5. EXPLODED VIEWS

5-1. Chassis Section ................................................................. 73

5-2. Front Panel Section ...........................................................74

5-3. CD Mechanism Section (1) ............................................... 75

5-4. CD Mechanism Section (2) ............................................... 76

5-5. CD Mechanism Section (3) ............................................... 77

6. ELECTRICAL PARTS LIST ........................................ 78

– 2 –

SECTION 1

GENERAL

This section is extracted from instruction manual.

– 3 –

– 4 –

– 5 –

– 6 –

– 7 –

– 8 –

– 9 –

– 10 –

– 11 –

– 12 –

SECTION 2

DISASSEMBLY

Note : Follow the disassembly procedure in the numerical order given.

2-1. COVER

claw

cover

claws

claw

2-2. FRONT PANEL ASSY

Push the bearing (L).

front panel assy

Push the button (open).

Push the bearing (R).

– 13 –

2-3. SUB PANEL ASSY

PTT 2.6x6

claws

CN804

sub panel assy

PTT 2.6x6

claw

CN801

2-4. MECHANISM BLOCK

bracket (mechanism deck)

PTT 2.6x6

mechanism block

CN401

PTT 2.6x

– 14 –

PTT 2.6x6

2-5. MAIN BOARD

)

ground point screw

(PTT 2.6x6)

MAIN board

PTT 2.6x10

ground point screws

(PTT 2.6x6)

sheet (insulating)

PTT 2.6x1

2-6. HEAT SINK

CN602

CN10

cord (with connector) (antenna

PTT 2.6x8

PTT 2.6x10

heat sink

– 15 –

PTT 2.6x10



EL inverter unit

PTT 2.6x10

PTT 2.6x8

2-7. CHASSIS (T) SUB ASSY

P 2x3

chassis (T) sub assy

P 2x3

claw

P 2x3

2-8. LEVER ASSY

lever (R) assy

tension spring (LR)

lever (L) assy

guide (disc)

PS 2x4

DISC IN SW board

claws

– 16 –

2-9. SERVO BOARD

loading motor assy

heat sink

!¡

SERVO board

PS 2x4

CN4

P 2x3

wire

PS 2x4

CN2

CN5

2-10. ROLLER ASSY

• When installing, take note of the positions

arm (roller) and washers. (Fig. 1)

PS 2x3

LOAD SW board

washer

arm washer

roller assy

arm (roller)

armwashers

Fig. 1

tension spring (RA)

– 17 –

2-11. CHASSIS (OP) (O/S) ASSY

compression spring (FL)

tension spring (angle)

Turn loading ring in the

direction of the arrow.

chassis (OP) (O/S) assy

compression spring (FL)

Fit lever (D) in the

direction of the arrow.

damper (T)

2-12. OPTICAL PICK-UP BLOCK

sled motor assy

P 2x3

damper (T)

optical pick-up block

– 18 –

SHUF

SECTION 3

ELECTRICAL ADJUSTMENTS

CD SECTION

CD section adjustments are done automatically in this set.

TUNER SECTION

0 dB = 1 µV

Cautions during repair

When the tuner unit is defective, replace it by a new one because its internal block is difficult to repair.

TEST MODE

This set have the test mode function. In the test mode, FM Auto Scan/Stop Level and MW Auto Scan/Stop Level adjustments can be performed easier than it in ordinary procedure.

1. Set the “OFF” mode.

2. Push the preset 4 button.

3. Push the preset 5 button.

4. Press the preset 1 button for more than two seconds.

5. Then the display indicates all lights, the test mode is set.

1. Push the OFF button.

Note on Adjustment

The adjustments of tuner section, should be performed according to the following sequence.

1. FM Auto Scan/Stop Level Adjustment

2. FM Stereo Separation Adjustment (WIDE)

3. FM Stereo Separation Adjustment (NARROW)

4. FM RDS S-Meter Adjustment

5. MW Auto Scan/Stop Level Adjustment

FM Auto Scan/Stop Level Adjustment

Setting :

SOURCE button: FM

FM RF signal generator

antenna

terminal

0.01

Carrier frequency : 98.00 MHz Output level : 22 dB (12.6 µV) Mode : mono Modulation : 1 kHz, 22.5 kHz deviation (30%)

Procedure :

1. Set to the test mode.

2. Push the SOURCE button and set to FM.

Display

3. Push the preset 3 button.

Display

SHUF

set

4. Adjust with the volume RV2 on TU10 so that the “FM”

indication turns to “FM0” indication on the display window. But, in case of already indicated “FM0”, turn the RV2 so that put out light “0” indication and adjustment.

Display

Adjustment Location : See page 22.

– 19 –

FM Stereo Separation Adjustment (WIDE)

Setting :

SOURCE button : FM1

FM Stereo Separation Adjustment (NARROW)

Setting :

SOURCE button : FM1

FM RF signal generator

0.01

Carrier frequency : 98.00 MHz Output level : 70 dB (3.2 mV) Mode : stereo Modulation : main : 1 kHz, 20 kHz deviation (26.5%)

sub : 1 kHz, 20 kHz deviation (26.5%) 19 kHz pilot : 7.5 kHz deviation (10%)

antenna terminal

set

10 k

Ω

LINE OUT REAR

Procedure :

FM stereo

signal generator

output channel

Level meter Level meter

connection reading (dB)

L-CH L-CH A

R-CH L-CH Adjust RV3 on TU10 for

minimum reading.

R-CH R-CH C

L-CH R-CH Adjust RV3 on TU10 for

minimum reading.

L-CH stereo separation : A – B R-CH stereo separation : C – D The separations of both channels should be equal.

Specification : Separation more than 24 dB

Adjustment Location : See page 22.

level meter

FM RF signal generator

0.01

Carrier frequency : 98.00 MHz Output level : 70 dB (3.2 mV) Mode : stereo Modulation : main : 1 kHz, 20 kHz deviation (26.5%)

sub : 1 kHz, 20 kHz deviation (26.5%) 19 kHz pilot : 7.5 kHz deviation (10%)

antenna terminal

set

10 k

Ω

LINE OUT REAR

Procedure :

1. Push the SHIFT button.

2. Push the 4 button three times.

3. Push the 5 button twice and set to NARROW mode.

FM stereo

signal generator

output channel

Level meter Level meter

connection reading (dB)

L-CH L-CH A

R-CH L-CH Adjust RV4 on TU10 for

minimum reading.

R-CH R-CH C

L-CH R-CH Adjust RV4 on TU10 for

minimum reading.

L-CH stereo separation : A – B R-CH stereo separation : C – D The separations of both channels should be equal.

Specification : Separation more than 18 dB

level meter

Adjustment Location : See page 22.

– 20 –

SHUF

AM RF signal generator

antenna terminal

AM dummy antenna(50

Ω

)

Ω

65 pF

15 pF

set

FM RDS S-Meter Adjustment

Setting :

SOURCE button: FM

FM RF signal generator

antenna

terminal

set

0.01

Carrier frequency : 98.00 MHz Output level : 35 dB (56.2 µV) Mode : mono Modulation : no modulation

Procedure :

1. Set to the test mode. (See page 19.)

2. Push the SOURCE button and set to FM. Display

SHUF

3. Push the preset 10 button.

4. Adjust RV10 so that the display indication is “13.0”. Display

SHUF

MW Auto Scan/Stop Level Adjustment

Setting :

SOURCE n MODE button : MW

Carrier frequency : 999 kHz 30% amplitude modulation by 1 kHz signal output level : 33 dB (44.7 µV)

Procedure :

1. Set to the test mode. (See page 19.)

2. Push the SOURCE button.

3. Push the MODE button and set to MW . Display

Specification : Display indication : 12.8 to 13.2.

Adjustment Location : See page 22.

4. Push the preset 3 button. Display

5. Adjust with the volume RV1 on TU10 so that the “MW”

indication turns to “MW0” indication on the display window. But, in case of already indicated “MW0”, turn the RV1 so that put out light “0” indication and adjustment.

Display

Adjustment Location : See page 22.

– 21 –

+ 49 hidden pages