Yamaha a 520 2

Page 1

THE QUALITY OF

THIS MANUAL IS

THE BEST THAT
IS AVAILABLE

STEREO INTEGRATED AMPLIFIER

A520

5 SERVICE MANUAL

I FRONT PANEL

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For Service Manuals Con
ON TECHNICAL SERIIIaCcES
SCheny Tree Rd, Chinnor
Oxan OX9 40V
meow-9351994 Fax 01844453554
:- enquiries@mawilton.m.tl<

IMPORTANT NOTICE

This manual has been provided for the use of authorized Yamaha Retailers and their service personnel,
lt has been assumed that basic service procedures inherant to the industry, and more specifically Yamaha
Products, are already known and understood by the users, and have therefore not been restatedl

WARNING: Failure to follow appropriate service and safety procedures when servicing this product
may result in personal iniury, destruction cf expensive components and failure or the
product to Periorm as specliiedd For these reasons, we advise all Yamaha product owners
that all scrylce required should be performed by an authorized Vamaha Retailer or the

appointed service representative.

IMPORTANT: The presentation or sale ul this manual to any individual or firm does not constitute
Julhurlzation, certIIiCallofl, recognition of any applicable technical CzpabiIItifls, or

establish a principlcagcnt relationship of any form.

The dam pruvlded is believed to be accurate and applicable to the unit]; indicated on the cover. The
research, engineering, and service departments of Yamaha are continually striving to improve Yamaha
products. Modifications are, therefore, Infllwble and changes in specification are subject to change without
notice or obligation to retrofit. Should any discrepancy appear to exist' please contact the distributors
Service Division.

WARNING: Static discharges can destroy expensive component; Discharge any static electricity your
body may have accumulated by grounding yourself re the ground buss in the unit (heavy

gauge black wires connect to this buss).

IMPORTANT: Turn the unit OFF during disassembly and parts replacement Recheck all work before
you apply power to the units

y

I CONTENTS

TO SERVICE PERSONNEL ................ 1 ADJUSTMENTS ..... . . . . . .. .......... 3
REAR PANEL .......... . .............. 1 PRINTED CIRCUIT BOARD ............... 4
BLOCK DIAGRAM . . . . . . . . ............. Z WIRING ............................. 4
SPECIFICATIONS ...................... 2 SCHEMATIC DIAGRAM .................. 5
INTERNAL VIEW ...................... 3 PARTS LIST ............ . . ........ 6"11
DISASSEMBLY PROCEDURES ....... . ..... 3

AA) YAMAHA

NIPPON GAKKI CO, LTD, HAM 'VTATSU, JAPAN

Page 2

A-52O

ITO SERVICE PERSONNEL

1. Critical Components Information.
Components having specnal characteristics are marked 2.
and must be replaced with parts having specifications equal
to those originally installed,

insulated from supply circuits.

by 0.15;:Ft

I REAR PANELS

V U.S.A. and Canadian models

EQUIPMENT AC LEAKAGE TESTER
2. Leakage Current Measurement (For 120V Model OnlyL UNDER TEST OFI EQUIVALENT
When service has been completed, it is imperative that you
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veri y that all exposed conductive sur aces are properly ® :0
0 Meter impedance should be equivalent to 1500 ohm shunted WALL E
OUTLET INSULATING TABLE 7
U Leakage current must not exceed 0.5mAt
- Be sure to test forleakage with the Ac plug in both palarities,
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Y General model

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@VMMA 3"

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V European model

(9mm: :3

3mm 6! "

For Service Man uals Contact
IMUfilTfiON TECHNICAL SERVICES
8 cherry Tree Rd Chinnor
Oxun OX9 4QY
76b 01344351694 Fax:- 01W
Emllz- ammrnam. no. uk