Yamaha rx 900 u

Page 1

STEREO RECEIVER

RX-900/900U

SERVICE MANUAL

VAMAIIA
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IMPORTANT NOTICE

This manual has bcen provided for the use of Rumorllad Yamaha Remilers and Chair service personnel. It has been assumed that basic Tervioe procedures inheranl to the
industry, an? more spacifically Yamaha Products. are already known and understood by lilo users, and have therefore not been reslaled. *

WARNING:

an authorizad Yamaha Retailer or an appointed service rcprcsentatiyc.

IMPORTANT: The prBsanLalan or Sale of fills manual in any individual or firm does not constlulle authorization, Certificarion, recognition of any applicablB wchnical

capabilitics, or asrablisli a principle-agent relationship of any form.

The data provided is believed to be accurate and applicable to the Imit(s) indicated an '37: cover. Tire research, engineering, and service departments or Yamaha are continually'
suiying re improve Yamaha products. Modifications are, Therefore, inevitable and specifications arc subieu to change wirncut neticc arobligarion to retrofit. Should any

discrepancy appear to GXISL please contact The distributor's Service Division.

WARNING:
buss in the unit (heavy gauge black wires connect to dlls buss .

IMPORTANT: Turn III: unir OFF during disassembly and parts replaumenl. Recheck all work bcfore you apply powsr to the units

Failur: to follow appmpriam seerC: and safety procedures when servicing Ibis product. may result in personal iniury, deerucllon of expensiv: componems
and failure of III: product in pzrfom'l as specified. For these masons, we aovise all Yamaha product owners ihat all service required should be performed by

Static discharges can destroy expensive components. Discharge any static Electricity your body may have accumuiarccl by grcunding yourself to The ground

I CONTENTS

TO SERVICE PERSONNEL . ..
REAR PANELS
SPECIFICATIONS .. .
INTERNAL VIEW....;.....
DISASSEMBLY PROCEDURES
ADJUSTMENTS
cowl DATA ......
CIRCUIT DATA

ICBLOCK ......
BLOCK DIAGRAM
WIRING.....
PRINTED CIRCUIT BOARD .
SCHEMATIC DIAGRAM ............ . .
PARTSLIST .............

REMOTE CONTROL TRANSMITTER . . . . .

YAMAHA

NIPPON GAKKl'COr, LTD, HAMAMATSU, JAPAN
1.8K-687 @ 6) Printed in Japan 873

SINCE 1887

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RX-900/900U

I TO SERVICE PERSONNEL

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

PMENT AC LEAKAGE TESTER

2. Leakage Current Measurement (For 120V Model Only). 53%;; TEST 0R EOUlVALENT

When service has been completed, it is imperative that you

verify that all exposed conductive surfaces are properly

insulated from supply circuits. ® D-
I Meter impedance should be equivalent to 1500 ohm shunted

by 015uF. WALL E: =

' OUTLET INSULATING TABLE

o Leakage current must not exceed 0.5mA.

0 Be sure to test for leakage with the AC plug in both polarities.

I REAR PANELS
o U.S.A. & Canadian models

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