HCD-W550, MHC-W550, MHC-W770AV - Sony Audio Service Manual (repair manual). Page 2

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• Supplying power during servicing

This equipment cannot operate without using a separate power supply. Connect to the STR-W550/W770AV when performing service
work.
To apply power set the SYSTEM POWER switch on the Tuner/Amp to ON.
When other units are not available use the PFJ-1 power supply jig.
When using the PFJ-1, simultaneously press the CD STOP button and the DECK A 

) (fast rightward) button to turn on the power.

[Connection Diagram]

PFJ-1

(Power Supply Jig)

POWER SW

FH-E939,838,737,
MHC-6600,5600,
CDP/TC

Connector Cable 17P
(Supplied with set)

Set

CNB108 17P
SYSTEM CONTROL

Conversion Board

(J-2501-138-A)

······································································ 3

2-1.

Back Panel, CD Block Removal ········································· 4

2-2.

Cassette Lid (A)/(B) Assy, Mechanism Deck  Removal ···· 4

2-3.

Main Board, Resistor Board, Front Panel Assy Removal ·· 5

3-1.

Mechanical Adjustment ······················································ 6

3-2.

Electrical Adjustment ························································· 6

4-1.

Block Diagram ································································· 11

4-2.

Circuit Boards Location ··················································· 13

4-3.

Schematic Diagram — Audio Section — ························· 14

4-4.

Printed Wiring Board — Audio Section — ······················ 17

4-5.

Printed Wiring Board — BD Section — ·························· 19

4-6.

Schematic Diagram — BD Section — ····························· 21

4-7.

Printed Wiring Board — Motor Section — ······················ 23

4-8.

Schematic Diagram — Motor Section — ························ 25

4-9.

Schematic Diagram — Panel Section — ························· 27

4-10. Printed Wiring Board — Panel Section — ······················· 29
4-11. Printed Wiring Board — Main Section — ······················· 32
4-12. Schematic Diagram — Main Section — ·························· 35
4-13. IC Block Diagrams ··························································· 38
4-14. IC Pin Function ································································ 40

5-1.

Main Section ····································································· 42

5-2.

Front Panel Section ·························································· 43

5-3.

CD Mechanism Deck  Section-1 (CDM38-5BD29A) ····· 44

5-4.

CD Mechanism Deck  Section-2 (CDM38-5BD29A) ····· 45

5-5.

Base Unit Section (BU-5BD29A) ···································· 46

5-6.

Tape Mechanism Deck Section-1 (TCM-220WR2E) ······ 47

5-7.

Tape Mechanism Deck Section-2 (TCM-220WR2E) ······ 48

··································· 49