Yamaha gx 900

Page 1

MINI COMPONENT SYSTEM

GX-SOO

SERV CE MANU

GX-900 is composed of GX-900 and NX-GXSOO.

\

/ IMPORTANT NOTICE .
This manual has been pl'mlded for rhe use of auihorized YAMAHA Reiailers and rheir service personnel.
Ii has been assumed ihai basic service procedures inhereni io ihe indusiry. and ruore specifically YAMAHA Prodllclsc are
already known and undersiood by rhe users. and have iherefore llol been resiaied.

WARNING: Failure in follow appropriare service and safery procedures when servicing ihis product may resuli in
personal injury. desiruciiori of expensive Componems, and failure of ihe produci to perform as specified.
For iliese reasons we advise all YAMAHA produci owners rhar any service required should be performed
by an auihorized YAMAHA Reiailer or ihe appoinied service i-epreseniaiive.

IMPORTANT: The preseuiarion or sale of ihis manual to any individual or firni does noi consmule aurhorizarion, certificar
rion or recogllmon of any applicable reohnical oapabiliiies. or esiablisli aprillcipleragelll relaiionship
of any forni,

The dara provided is believed to be accuraie and applicable ro rhe ullil(s) indicaied on rhe cover The research. engineering and
serVice depai-rnienrs of YAMAHA are coniinually SUIVIIIg ro iinproye YAMAHA producrs. Modificaiions are. rberefore.
ineviiable and specificaiipns are subjeci To change wuhouf noiice or obligaiiml io reirofii. Should any dIscrepancy appear io
exisl. please conracr rhe disiribuior's Service Division,

WARNING: Siaric discharges can desimy expensive ooniponenrs. Discharge any sraiic eleciriciry your body may have
acouniulared by grounding yourself io the ground buss in ihe unir (heavy gauge black was Connecl io ihis
buss),

IMPORTANT: Turn ibe unii OFF during disasseinbly and pari replaceineni. Reclleck all work before you apply power io ihe

unii.

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I CONTENTS

TO SERVICE PERSONNEL .
FRONT PANELS

TAPE ADJUSTMENTS .....................
MD TEST MODE & ADJUSTMENTS

----- MD ERROR DISPLAY .......
M-D TRO :JBLESHOOTINGI.

_-
DISASSEMBLY PROCEDURES
VOLUME RANGE .................
SYSTEM CONTROL CHECK

TEST MODEI. ...............

IC DATA

DISPLAY DATA .

-17 Elm KDIA RAM

-17 MD TE T P INT WAVEF RM
.18 PRINTED CIRCUIT BOARD

SYSTEM TEST MODE .13 PIN ONNE TI'N DIA RAM
RECEIVER TEST MODE .19~20 SCHEMATIC DIAGRAM

TAPE TEST MODE ..

91~117

.20 PARTS LIST ..
118~120

-21 GREASE APPLICATION DIAGRAM
LL FUNCTION TEST MODE. .22 REM TE NTR L TRAN MI'I'I'ER _

D ERROR MESSAGES . 22 NX-GX500
D STANDARD OPERATION CHAR ................ 23~26

DUDEDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
This Service Manual uses recycled paper.0
amu i;

YAMAHA

YAMAHA CORPORATION
PO. Box 1. Hamamatsu. Japan

Page 2

G X-900

I TO SERVICE PERSONNEL

1. Critical Components lnlormation.
Components having special characteristics are marked and
must be replaced with parts having specifications equal to
those originally installed.

AC LEAKAGE

WALL EQUIPMENT TESTER OR

OUTLET UNDER TEST EQUIVALENT
INSULATING _

TABLE

CAUTION: USE OF CONTROLS OR ADJUSTMENTS OR PERFORMANCE OF PROCEDURES OTHER THAN THOSE
SPECIFIED HEREIN MAY RESULT IN HAZARDOUS RADIATION EXPOSURE

THE COMPACT DISC PLAYER/MINI DISC RECORDER SHOULD NOT BE ADJUSTED OR REPAIRED BY ANYONE

EXCEPT PROPERLY QUALIFIED SERVICE PERSONNEL.

PROTECTION OF EYES FROM LASER BEAM DURING SERVICING

This set employs a laser. Therefore, be sure to carefully follow the instructions below when servicing .

CD Laser Diode Properties

0 Material : GaAlAs

o Wavelength : 780 nm

0 Emission Duration :Continuous

0 Laser Output : max. 44.6 LIW

This output is the value measured at a distance of
about 200 mm from the objective lens surface on
the Optical Pick-up Block.

MD Laser Diode Properties

0 Material : GaAlAs
o Wavelength : 785 nm
0 Pulse time:
Read mode 0.8 mW Continuous

Write mode max 10 mW 0.58
min cycle 1.58
Repetition

When checking the laser diode emission, keep your eyes more than 30 cm away from the objective lens.

(2) B, G models

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(D B, G models

CLASS I LASER PRODUCT