Marantz EQ 551 Service Manual

Page 2

Using superior design and selected high grade
components, MAFIANTZ company has created the

MARANTZ DESIGN AND SERVICE

ultimate in stereo sound.

Only original MARANTZ parts can insure that your
MARANTZ product will continue to perform to the

specifications for which it is famous.

Parts for your MARANTZ equipment are generally
available to our National Marantz Subsidiary or Agent.

ORDERING PARTS:

Parts can be ordered either by mail or by telex. In both
cases. correct part number has to be specified. If you

order by mail, fulfil MARANTZ order forms.

The following information must be supplied to eliminate
delays in processing your order:

1. Complete address

Complete pan numbers and quantles required
Description of parts

Way of shipment

2.
3.
4. Model number for which part Is required
5.
6.

TECHNICAL ASSISTANCE

Should you require any other technical support. do not
hesitate to contact the Technical Department of
MARANTZ EUROPE 3. Co.
Avenue Louise 326 - Etc. 32
B-1050 Brussels

Belgium

Telephone: (02) 6407830 (10 I)
Telex: 26602

Fax: (02) 649.29.20

Signature: any order form or telex must be signed
otherwise such part order will be considered as null

and void.

PARTS ORDERING

Parts may be ordered at the following addresses:

AUSTRIA

HORNYPHON
Vertriebsgesellschaft Gmbtl
Wienerbergatraase 1

A 1101 Wien

Austria

Telex: 132.332

AUSTRALIA
MARANTZ AUSTRALIA
PTY.. Ltd.

19 Chard Road
Broohvaie. NSW 2100
Australia

Telex: 24121

IELGIUM

SVD DIVISION MARANTZ
lndustrlelasn I

1720 Groot-BIIgaarden
Belgium

Telex: 24465

MILE

MARANTZ

DIVISION OF PHILIPS S.A.
AV. Santa Marie. 0780
Cecilia 2087

Santiago

Telex: 240.239

DENMARK

MARANTZ

DIVISION OF PHILIPS
SERVICE AIS

Frags Boulevard 00
Postbox 1919
DK-2300 Kebenhavn S
Denmark

Telex: 31201

EIRE

MARANTZ IRELAND Ltd.
Newsteed

Glonkeagh

Dublin 4

Telex: 25200

FINLAND

MARANTZ

DIVISION OF OY PHILIPS Ab
Kelvokatu 0

00100 Helsinki

Finllnd

Telex: 124811

FRANCE

MARANTZ FRANCE
4 Rue Bernard Pallssy
92000 Asnleres
France

Telex: 011651

GERMANY

MARANTZ GERMANY GmbH
Max-Plancit-Strasae 22

6072 Drelelch 1

Germany

Telex: 529821

THE NETHERLANDS
MARANTZ

De leiet 3

4131 NR Vlanen
The Netherlands
Telex: 47679

NORWAY

MARANTZ

DIVISION OF PHILIPS AIS
Sendstuveien 40

Oslo 6

Norway

Telex: 72840

onur serum
MARANTZ AUDIO U.K. 1.1a
um 15/16

Saxon Way Industrial Estate
Moor Lane

Harmcndeworth uar otw
Great Britain

Telex: sesm

CREE

ADAMCO S.A.
P.O.Box 21025
Hlppocratue Street 103
Athens 11410

Greece

Telex: 216.795

ITALY

MARANTZ ITALIANA S.p.A.
Vla Monte Nepoleone 10
20121 Mllanc

Italll

JAPAN

MARANTZ JAPAN. lnc.
35-1. 7-chorne. sagamiono
Segamihara-shl. Kanagawa
Japan

KUWAIT

AL ALAMIAH ELECTRONICS
Usaarna Building

Fahd al Saleem Street
P.O.Box 23701

Sam-Kuwait

Telex: 22994

SAUDI ARABIA

AL ALAMIAH ELECTRONICS
P.O.Box 5064

University 80001

Rlyedh 11432

Sludl Arabia

Telex: 201530

IOUTH AFRICA
MARANTZ

DIVISION OF PHILIPS S.A.
Rainer Home '

Ove Street. 10
Doornfornaln
Johannesburg

Telex: 403.456

sum

mono S.A.

lgnscio We 10
Badllofll (Barcelona)

Spain
Telex: 59055

SWEDEN

MARANTZ

DIVISION OF PHILIPS
Forsllimng AB
Tegefuddavlgen 1

5-1 15 04 Stockholm
Sweden

Telex: 14000

IWITIERLAND
DYNAVOX ELECTRONICS
Route de Villars 105

1101 Frloourg
Switzerland

Telex: 942377

TURKEY
DOGRUOL Ltd.
I.M.C.

0 Biol: M8310
Unkapanl
istanbui
Turkey

Telex: 22m

MALTA

CACHIA G GALEA
Republic Street. GOD
Vim

Telex: 1082

U.

MARANTZ COMPANY, Inc.
National Service Department
PtOBox 577

Chetewonh. CA 91311
U.S.A.

All of the above locations are fully equipped to take care of your total service needs. Because various countries have
differing configuration requirements, it Is necessary that you contact the service facility In your particular country. In
the event that there is no service location listed for your country, please. contact the nearest facility for the necessary

IDIISIRCD.

M 19.9

in case of difficulties. do not hesitate to contact the Technical
Department at abovernentioned address.

maranll:

TABLE OF CONTENTS

SECTION PAGE
INTRODUCTION ................................................................ 1
1. SHOCK, FIRE HAZARD SERVICE TEST ......................................... 1
2. PW. BOARDS ................................................................. 1
3, VOLTAGE CONVERSION ...................................................... 2
4 CIRCUIT DESCRIPTION ...................................................... 2
MOS TC50643P (OL07, OLOB) ........................................................ 2
M08 4514 (OLOBI ................................................................ 3
5. BLOCK DIAGRAM ............................................................ 4
6 SCHEMATIC DIAGRAM AND COMPONENT LOCATIONS .......................... 5
6.1 Input Switch Assembly (P515) Schematic Diagram and Component Locations ...................... 5
6.2 Display Switch Assembly (P525) Schematic Diagram and Component Locations .................... 5
6.3 Mic Amp. Assembly (PV15I Schematic Diagram and Component Locations ........................ 6
6.4 Power Switch Assembly (P835) Schematic Diagram and Component Locations ..................... 7
6.5 Bar Drive/Volume Assembly (PR15) Schematic Diagram and Component Locations .................. 7
6.6 Main Assembly (PE15) Schematic Diagram and Component Locations ........................... 8
6.7 FL Set Assembly (PR25) Schematic Diagram and Component Locations .......................... 10
7. TECHNICAL SPECIFICATIONS .................................................. 11
8. EXPLODED VIEW AND PARTS LIST ............................................ 12
9. ELECTRICAL PARTS LIST .................................................... 14
10. SCHEMATIC DIAGRAM ........................................................ 16

9 x xxx x xxxxxx xxx x I1

g II

It How to use this service manual §

ll i

It a The "Common parts" which Marantz Japan, Inc. has established are eliminated from this II

a service manual. II

* e :hfien'Common parts" are applied to all models in the service manuals arranged and issued E

II V - ll

§ e To indicate clearly the common parts in the schematic diagram, 3 line is drawn above or A

9 under the Rat. Desig. No. of applicable parts. g

it e "Common parts" can be supplied from the Marantz service center as ever. Ii

it In case of ordering, please establish the parts number of 10 figures following the procedure I1

§ mentioned In this service manual "How to establish the parts number for common parts". g

it more) ii

g When you order parts to the Marantz parts center, please take notice of the following points. a

it 1) Please correctly write the parts number of 10 figures follownng the rule ii

a 2) Since ordering parts by the Ref. DeSIg. No. or ratings indicated in the schematic diagram *

ll does not satisfy the above conditions, the Marantz parts supply system does not work g

proper v,

a As this case is apt to cause a trouble, please pay attention to it. §

ll it

i ll

Lnnxxxxxxxxxxxxxxxxxxzxxxxxxxxxxxxxxxxxxxmg

#3/57