Sony hcd gtr 88 service manual

Page 2

HCD-GTR88

NOTES ON CHIP COMPONENT REPLACEMENT

0 Never reuse a disconnected chip component.

' Notice that the minus side of a tantalum capacitor may be damA
aged by heat.

FLEXIBLE CIRCUIT BOARD REPAIRING

. Keep the temperature of 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 unsolA
dering.

SAFETY CHECK-OUT

After correcting the original service problem. perform the following safeA
ty check before releasing the set to the customer:

Check the antenna terminals, metal trim, metallized knobs, screws, and
all other exposed metal parts for AC leakage.

Check leakage as described below.

LEAKAGE TEST

The AC leakage from any exposed metal part to earth ground and from all

exposed metal parts to any exposed metal part having a return to chassis,

must not exceed 0.5 mA (500 microamperes.). Leakage current can be
measured by any one of three methods.

1. A commercial leakage tester, such as the Simpson 229 or RCA WTA
540A. Follow the manufacturers instructions to use these instruA
ments.

2. A batteronperated AC milliammeter. The Data Precision 245 digital
multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by means of a VOM or
battery-operated AC voltmeter. The limit" indication is 0.75 V, so
analog meters must have an accurate lowAvoltage scale. The Simpson
250 and Sanwa SHA63Trd are examples of a passive VOM that is
suitable. Nearly all battery operated digital multimeters that have a 2
V AC range are suitable. (See Fig. A)

To Exposed Metal
Parts on Set
AC
0.15pF g 1.5 k0 / voltmeter
(a. 75 V)

_7_ Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.

CAUTION

Use of controls or adjustments or perlormance of procedures
other than those specified herein may result in hazardous radia-
tion exposure.

cuss 1 LASER PRODUCT This appliance is classified as a CLASS 1
LUOKAN i msgaer LASER product. This marking is located on

KLASSi LASERAPPARAT

the rear exterior,

SAFETY-RELATED COMPONENT WARNING!

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

2

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oxcpcsos
P9P:-

10. POWER AMP Board, SUBWOOFER Board
. Chassis Section....
12. CD Mechanism Block (CDMSSBL-DVBUlOl)
. Optical PickAup Block (KHMA313CAB)

. Schematic Diagram A DMB19 Board (3/3) A
. Printed Wiring Board A POWER AMP Board A
. Schematic Diagram A POWER AMP Board A
. Printed Wiring Board A MAIN Board A ..
. Schematic Diagram A MAIN Board (1/3) A
. Schematic Diagram A MAIN Board (2/3) A
. Schematic Diagram A MAIN Board (3/3) A
. Printed Wiring Board A MIC, VOL and USB Board A
. Schematic Diagram A MIC, VOL and USB Boards .
. Printed Wiring Board A TC Board
. Schematic Diagram A TC Board A
. Printed Wiring Board

. Printed Wiring Board A SUBWOOFER Board A.
. Schematic Diagram A SUBWOOFER Board
. Printed Wiring Board A HUB Board A ....... ..
. Schematic Diagram A HUB Board A ................................ 42

TABLE OF CONTENTS
SERVICING NOTES.

DISASSEMBLY
Disassembly Flow ...........................................................
Case (SideAL/R)
Top Case.
Tape Mecha
Front Panel Block, HUB Board, DMB19 Board
DC Fan (M101) .....................
Back Panel, SUBTRANS Boar
MAIN Board ...........................
DC Fan (M101), PT SHIELD Board,
POWER AMP Board Section ......

w

. Belt (DLM3A) .........................
TEST MODE.
MECHANICAL ADJUSTMENTS ....................... 15
ELECTRICAL ADJUSTMENTS ......................... l6
DIAGRAMS

Block Diagram A RF SERVO, USB Section A
Block Diagram A MAIN Section A
Block Diagram A AMP Section A..
Block Diagram A DISPLAY,

POWER SUPPLY Section A ............
Printed Wiring Board A DISPLAY Board A
Schematic Diagram A DISPLAY Board A
Printed Wiring Board A DMB19 Board A
Schematic Diagram A DMB19 Board (1/3) A
Schematic Diagram A DMB19 Board (2/3) A

A TRANS and SUBTRANS Board A ............................... 37

. Schematic Diagram

A TRANS and SUBTRANS Boards A .............................. 38

EXPLODED VIEWS
Case Section.
Top Panel Section
Loading Panel Section, HUB Board Sec on,
DMB19 Board Section...
DISPLAY Board Sectio
Front Panel Sectio
Back Panel Sectio
MAIN Board Section.
Chassis Section
CD Mechanism Section (CDMSSBLADVBUIOI).

ELECTRICAL PARTS LIST ............................... 62