Sony XR-4954X Service Manual

XR-4950X/4954X

SERVICE MANUAL

Photo: XR-4950X

SPECIFICATIONS

E Model

Model Name Using Similar Mechanism XR-C5100
T ape Transport Mechanism Type MG-25F-136

MICROFILM

FM/MW/SW CASSETTE CAR STEREO

TABLE OF CONTENTS

1. SERVICE NOTE ............................................................. 2

2. GENERAL ........................................................................ 3

3. DISASSEMBLY .............................................................. 13

Flexible Circuit Board Repairing

• Keep the temperature of the soldering iron around 270 ˚C dur­ing repairing.

• Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).

• Be careful not to apply force on the conductor when soldering
or unsoldering.

4. ASSEMBLY OF MECHANISM DECK................ 14

5. MECHANICAL ADJUSTMENTS ............................ 17

6. ELECTRICAL ADJUSTMENTS

6-1. Test Mode........................................................................ 17

• Tape Deck Section ........................................................ 17

• Tuner Section................................................................ 17

7. DIAGRAMS

7-1. Block Diagrams

• TUNER/TAPE/MAIN Section ..................................... 18

• DISPLAY/KEY CONTROL/BUS CONTROL/

POWER SUPPLY Section ........................................... 19

7-2. Printed Wiring Board – MAIN Board – ......................... 21

7-3. Schematic Diagram – MAIN Board (1/2) – ................... 22

7-4. Schematic Diagram – MAIN Board (2/2) – ................... 23

7-5. Printed Wiring Boards – KEY/SUB Boards – .............. 24

7-6. Schematic Diagrams – KEY/SUB Boards – .................. 25

7-7. IC Block Diagrams ......................................................... 26

7-8. IC Pin Function ............................................................... 27

8. EXPLODED VIEWS................................................ 32

9. ELECTRICAL PARTS LIST ............................... 35

Notes on chip component replacement

• Never reuse a disconnected chip component.

• Notice that the minus side of a tantalum capacitor may be dam­aged by heat.

SERVICE NOTE

Please press on the sub board from above when checking it.
This assures that the connector does not lose contact.

SUB board

SECTION 1

Front panel assembly

2

SECTION 2

GENERAL

This section is extracted from
instruction manual.

3

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