Marantz 74 PM52/00B User manual

74 PM52/00s/018/028
/02G/05B/07B
Integrated amplifier
This
service
manual
explains
them
by
extracting
the
different
specifications
from
those
of
the
model
PM-5O,
based
on
the
model
PM-50.
For
both
electrical
and
mechanical
infor-
mation
on
the
after-sales
service
which
is
not
stated,
all
information
is
described
in
the
mode!
PM-50
service
manual
(Codenumber
4822
725
50885).
The
dispatch
of
the
parts
for
after-sales
service
has
to
be
referred
to
this
service
manual,
with
the
first
priority.
For
this
reason,
please
use
this
service
manual
with
referring
to
the
model
PM-50
service
manual,
without
fail.
7
20
model PM-52
Fist issue;1991
4822 725 50944
. MZ 2892

MARANTZ DESIGN AND SERVICE
Using superior design and selected high grade components,
MARANTZ company has created the 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 at our
National Marantz Subsidiary or Agent.
ORDERING PARTS
MARANTZ EUROPE B.V.
P.O. Box 80002
Building SFF 2
5600 JB Eindhoven
The Netherlands
Phone : [phone]
Fax : [phone]
Parts can be ordered either by mail or by telex. In both cases, the correct part number has to be specified.
The following information must be supplied to eliminate delays in processing your order:
1. Complete address
2. Complete part numbers and quantities required
3. Description of parts
4. Model number for which the part is required
5. Way of shipment
6. Signature: any order form or telex must be signed,
otherwise such part order will be considered as null and void.
ADDRESSES
AUSTRIA FRANCE ITALY
MARANTZ MARANTZ FRANCE MARANTZ ITALIANA SPA
Hietzinger Kai 137a 4 Rue Bernard Palissy Piazza !V Novembre 3
1130 Wien 92600 Asniéres 20124 Milano
Austria France Italy
BELGIUM GERMANY JAPAN
MARANTZ EUROPE B.V.
MARANTZ GERMANY GmbH
MARANTZ JAPAN INC.
Div. Benelux Alexanderstrasse 1 35-1, 7-chome, Sagamiono
P.O.Box 80002 2000 Hamburg Sagamihara-shi, Kanagawa
Building SFF 2 Germany Japan
5600 JB Eindhoven
The Netherlands
CHILE GREAT BRITAIN KUWAIT
MARANTZ DIVISION OF MARANTZ HiFi UK Ltd. AL ALAMIAH ELECTRONICS
PHILIPS S.A. Kingsbridge House P.O.Box 8196
Av.Santa Maria 0760 Padbury Oaks Salmiah
Casilla 2687 575-583 Bath Road 22052 Kuwait
Santiago Longford Middlesex UB7 OEH,
Chile U.K.
DENMARK GREECE NETHERLANDS
MARANTZ ADAMCO ELECTR. SA MARANTZ EUROPE B.V.
Horsvinget 5
P.O.Box 21025 Div. Benelux
2630 Tastrup Hippocratus Str. 188 P.O.Box 80002
Denmark Athens 11471 Building SFF 2
Greece 5600 JB Eindhoven
The Netherlands
FINLAND
MARANTZ
Kuortanegatan 1
00520
Helsingfors 52
Finland
NORWAY
MARANTZ
Postboks 7034
Assiden
3007 Drammen
Norway
PORTUGAL
COREL
Av. da Liberdade
211-2 Esq.
1200 Lisboa
Portugal
SAUDI ARABIA
AL ALAMIAH ELECTRONICS
P.O.Box 5954
University Street
Riyadh 11432
Saudi Arabia
SOUTH AFRICA
MARANTZ S.A.
10 Bond Street
Randburg 2194
P.O. Box 7703
Johannesburg 2000
South Africa
SPAIN
MARANTZ SPAIN
Martinez Villergas 2
Apartado 2065
Madrid 28027
Spain
SWEDEN
MARANTZ
Box 1324
17125 Solna
Sweden
SWITZERLAND
MARANTZ SWITZERLAND
Postfach
8010 Zurich
Switzerland
TRADING
MARANTZ TRADING
P.O.Box 20008
Building SFF 2
5600 JB Eindhoven
The Netherlands
All of the above locations are fully equipped to take care of your total service needs or can advice you. 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 assistance.
In case of difficulties, do not hesitate to contact the
Technical Department at above mentioned address.

Different Parts between model PM-50 and PM-52
REF. DESIG.
PM-50
PM-52
DESCRIPTION
001B
4822 425 40173
4822 425 40174
4822 413 41582
4822 736 20422
4822 253 30027
4822 253 30191
4822 264 30266
4822 447 50147
4822 447 50148
4822 413 31582
4822 736 21152
4822 253 30191
4822 070 33152
4822 267 40663
Front Panel Assembly (BLK)
/00B/018/02B/05B/07B
Front Panel Assembly (GLD) /02G
Knob, Selector (GLD) /02G
User Manual
Fuse, T1.6A 250V /01B
Fuse, T3.15A 250V /01B
Jack, AC Outlet /01B
4822 267 31126
4822 267 31119
4822 267 31274
4822 267 31365
Jack, Headphone (BLK)
/00B/01B/02B/05B/07B
Jack, Headphone (GLD) /02G
4822 280 20195
4822 121 51008
4822 121 51008
4822 116 60342
4822 116 60342
4822 116 52348
4822 116 52348
4822 116 80648
4822 290 60837
4822 290 60836
4822 116 52976
4822 116 53479
4822 116 52976
4822 116 53479
4822 124 23081
4822 124 23081
4822 130 60525
4822 130 60525
4822 130 60524
4822 130 60524
4822 130 60116
4822 130 60116
4822 130 60109
4822 130 60109
pone
4822 116 81748
4822 116 81748
4822 280 20464
4822 121 51008
4822 121 51008
4822 116 80648
4822 116 60338
4822 116 60447
4822 290 60837
4822 290 60841
4822 290 60836
4822 290 60839
4822 050 21008
4822 050 22209
4822 050 21008
4822 050 22209
4822 124 23762
4822 124 23762
4822 122 30043
4822 122 30043
4822 130 62738
4822 130 62738
4822 130 62737
4822 130 62737
3302 £2% 1/4W, Fusible /02B/02G/05B
3302 +2% 1/4W, Fusible /02B/02G/05B
Relay
Film 10uF 50V /00B/01B/05B/07B
Film 10uF 50V /00B/01B/05B/07B
3302 10uF 3W, Metal /00B/01B/07B
1502 10uF 2W /02B/02G/05B
1802 10uF 1/2W /02B/02G/05B
Terminal, Speaker /O0B/01B/05B/07B
Terminal, Speaker /02B/02G
Terminal, Speaker /00B/01B/05B/07B
Terminal, Speaker /O02B
12 +5% 1/4W /00B/01B/07B
222 +5% 1/4W /00B/01B/07B
12 +5% 1/4W /00B/01B/07B
222 +5% 1/4W /00B/01B/07B
Elect Cap. 8200uF 56V
Elect Cap. 8200uF 56V
Ceramic 0.01uF +80% —20% /02B
Ceramic 0.01uF +80% —20% /02B
Transistor 2SD2276 (P, Q)
Transistor 2SD2276 (P, Q)
Transistor 2SB1503 (P, Q)
Transistor 2SB1503 (P, Q)
MZ 2893

‘IDLING CURRENT ADJUSTMENT
(1) Before switching the power ON, set the Master Volume
control to the minimum position and the Balance and
Tone controls to the center positions. Also set semi-fixed
resistors R719 (L CH) and R720 (R CH) on PCB P701 to
the center positions.
(2) Each of the cement resistors R743 (L CH) and R744 (R
CH) on the PCB P701 is provided with three test points.
Connect a digital voltmeter, set for the DC voltage input,
to the test points at the two extremities of the three
test points of R743 or R744
(3) After the setup above, switch the power ON and adjust
semi-fixed resistor R719 (L CH) or R720 (R CH) on
PCB P701 according to the digital voltmeter reading.
The target setting value is 8 mV ( 22 mA ) for both the
L CH and R CH.
Please refer to the table below.
Elapsed time after power ON Idling current setting value
30 sec. — 1 min. 7.5 mV
T min. — 2 min, 8 mV
2 min. — 4 min. 8 mV
More than 4 min. 8mvV
Note on Safety:
Symbol @ Fire or electrical shock hazard. Only original
parts should be used to replace any part marked with
symbol &, Any other component substitution (other
than original type), may increase risk of fire or electrical
shock hazard,
MZ 2894

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MARANTZ DESIGN AND SERVICE
Using superior design and selected high grade
components, MARANTZ company has created the
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
MARANTZ INTERNATIONAL
Vestdijk 9
5600 MD_ Eindhoven
The Netherlands
Phone: [phone]
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.
The following information must be supplied to eliminate
delays in processing your order:
DIVISION OF PHILIPS S.A.
AV. Santa Maria, 0760
Casilla 2687
Santiago
Telex: 240.239
DENMARK
MARANTZ
- DIVISION OF PHILIPS
SERVICE A/S
Prags Boulevard 80
Postbox 1919
- DK-2300 Kebenhavn S
Denmark
Telex: 31201
Max-Planck-Strasse 22
6072 Dreieich 1
Germany
Telex: 529821
THE NETHERLANDS
Elpro Marantz
Wint Hontiaan 28
3526 KV Utrecht
The Netherlands
Telex: 4748
NORWAY
MARANTZ
DIVISION OF PHILIPS A/S
Sandstuveien 40
0680 Oslo 6
Norway
Telex: 72640
st be signed
GREAT BRITAIN
MARANTZ AUDIO U.K. Ltd
Unit 15/16
Saxon Way industrial Estate
Moor Lane
Harmondsworth UB7 OLW
Great Britain
Telex: 935196
GREECE
SHERTON ELECTRONICS S.A.
P.O.Box 21025
Hippocratus Street 188
Athens 11471
Greece
Telex: 216.795
1. Complete address
2. Complete part numbers and quantities required
3. Description of parts
4. Model number for which part is required
5. Way of shipment
6. Signature: any order form or telex mu
otherwise such part order will be considered as null
and void.
PARTS ORDERING
Parts may be ordered at the following addresses:
AUSTRIA FINLAND
HORNYPHON MARANTZ
Vertriebsgeselischaft GmbH DIVISION OF OY PHILIPS Ab
Wienerbergstrasse 1 Kaivokatu 8
A1101 Wien 00100 Helsinki
Austria Finland
Telex: 132.332 Telex: 124811
‘BELGIUM FRANCE
SVD DIVISILN MARANTZ MARANTZ FRANCE
industrialaan 1 4 Rue Bernard Palissy
1720 Groot-Bijgaarden 92600 Asniéres
Belgium France
Telex: 24466 Telex: 611651
CHILE GERMANY
MARANTZ MARANTZ GERMANY GmbH
JAPAN
MARANTZ JAPAN, Inc.
35-1, 7-chome, Sagamiono
Sagamihara-shi,,Kanagawa
Japan : :
KUWAIT
AL ALAMIAH ELECTRONICS
Ussama Building
Fahd al Saleem Street
P.O.Box 23781
Safat-Kuwait
Telex: 22694
ITALY
MARANTZ ITALIANA S.P.A.
Via Chiese, 74
20126 Milano
Italy
Telefax: +31 /40.75.82.99
SAUD! ARABIA
AL ALAMIAH ELECTRONICS
P.O.Box 5954
University Street
Riyadh 11432
Saudi Arabia
Telex: 401530
SOUTH AFRICA
MARANTZ
DIVISION OF PHILIPS S.A.
Main Road Martindaie
P.O. Box. 58088
Newville 21114
South Africa
SPAIN
PHONO S.A.
Ignacio Iglesias 10
Badalona (Barcelona)
Spain
Telex: 59355
" SWEDEN
MARANTZ
DIVISION OF PHILIPS
Férsaljning AB
Tegeluddsvagen 1
S-115 84 Stockholm
Sweden
Telex: 14060
Telex: 35000 PHTC NL routing IND NLMTFAT
SWITZERLAND
DYNAVOX ELECTRONICS
Route de Villars 105
1701 Fribourg
Switzerland
Telex: 942377
TURKEY
DOGRUOL Ltd.
1.M.C.
6 Blok N°6310
Unkapani
Istanbul
Turkey
Telex: 22085
MALTA
CACHIA & GALEA
Republic Street, 68D
Valetta
Telex: 1682
PORTUGAL
MARANTZ
Divisao philips S.A. sirvice
Outurela-carnaxide
2795 LinDA-A-VELHA
Telex: 43906
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
necessar
In
case
of
difficulties,
do
not
hesitate
to
contact
the
Technical
Department
at
abovementioned
address.
..
assistance.

MODEL PM-50 INTEGRATED AMPLIFIER
WER WORM BR EAL srzanarce anemic ower
TABLE OF CONTENTS
Section
Page
1
BLOCK:
DIAG
RAMexs
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das
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leh
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Bie
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2. SCHEMATIC: DIAGRAM ois eee ook ees wake ba be ee eee ig a ae i ied Mae Rae Le Ss ta 5
3. PARTS LOCATIONS (Pattern Side)... ...... 6 eee c eee eet ee ee ee nee e enn e enn es 8
4.
EXPLODED
VIEW
AND
PARTS
LIST
..
0...
cee
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nee
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teen
ete
12
5.
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CURRENT
ADJUSTMENT
.......
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14
6.
HOW
TO
CHANGE
THE
SUPPLY
VOLTAGE
(A/N/T/W
Version)
..
0.2.0.0.
cee
eee
ent
nees
14
7.
TEST
EQUIPMENT
REQIRED
FOR
SERVICING
....
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cee
te
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15
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VOLTAGE
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9.
ELECTRICAL
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16

TECHNICAL SPECIFICATIONS (DIN)
Power Amplifier Section
IHF Dynamic Power
2 ohms
4 ohms
8 ohms
Power Output Per Channel
DIN 4 ohms 1 kHz 1% THD
RMS 4ohms = 1 kHz 0.06% THD
DIN 8 ohms 1 kHz 1% THD
RMS 8 ohms = 1 kHz 0.06% THD
FTC4ohms 20-20 kHz 0.06% THD
FTC8o0hms 20—20 kHz 0.03% THD
Total Harmonic Distortion at 8 ohms
I.M. Distortion at 8 ohms
Damping Factor
Slew Rate
Phono Amplifier Section
MM Cartridge Input
Frequency Difference
Signal to Noise Ratio (A weighted)
Input Sensitivity
Input Impedance
MC Cartridge Input
Input Sensitivity
Input Impedance
Hight Level Section
Frequency Response
Signal to Noise Ratio (A weighted)
Input Sensitivity
Input Impedance
Tape Output Level [Phono (MM) 5 mV 1 kHz Input]
Tape Output Impedance (Phono)
Tone Control Action 100 Hz
10 kHz
(CD Input at 1 kHz)
(CD Input at 10 kHz)
Channel Separation
General
Power Requirements
2 Voltage version
4 Voltage version
Power Consumption (Rated Power)
AB Class Moode
A Class Moode
Dimensions
Panel Width
Pane! Height
Depth
Weight
Unit alone
: 240W
: 150W
: 95W
: 120W
: 105W
: 75W
: 7OW
: 95W
: 7OW
: 0.008%
: 0.008%
: 100
: 70 V/ps
: +0.5 dB
: 86 dB
: 2.5mm
: 47k Ohms
: 0.25 mV
: 100 Ohms
: 10—70 kHz
: 86 dB
: 150 mV
: 33k Ohms
: 300 mV
: 220 Ohms
: £6 dB
: +6 dB
: 75 dB
: 65 dB
: 220V/240V
: 110V—240V
: 300W
: 420 mm
: 132 mm
: 334 mm
: 10 kg
Specifications and appearance are subject to change for modification without notice.

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3. PARTS LOCATIONS (Pattern Side)
P701 Power Amp.
@709
Q710
Q706
Q705
701
Q702
Q704
Q703
Q708
Q707
Q711
712
QNO3QNO2
QNO4QNOI
PJO1
Tape
IN/OUT
avis Q7I3 Q7I4
PV01 Phono Amp./Inp
P851 Power S'
PY01 Tape Indicator
i
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t
4
i
j
H
|
aR
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1
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[Reine
MARA-00480 / Druck 3

Q711 Q712 GNO3QNOZ QNO4 GN! PJO1 Tape IN/OUT
Phono Amp./Input Select
RTM
—
u
le AS SANE
ge
CURR RRR
P851_
Power
Supply
P951
Transformer/Fuse
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On
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P3801
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MARA-004884 Fora 5
Small Power Supply
PGO1
P901
Q80! 9802
Master Volume
Power Switch
11
4. EXPLODED VIEW AND PARTS LIST
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4.
EXPLODED
VIEW
AND
PARTS
LIST
——_—_——
Front Panel Assembly (BLK)
ear. | PART NO.
4822 425 40173
4822 425 40174 | Front Panel Assembly (GLD)
4822 413 41544 | Knob, Volume (BLK)
4822 41341542 | Knob, Volume (GLD)
4822 413 41545 | Knob, Selector (BLK)
4822 413 41582 | Knob, Selector (GLD)
4822 413 31551 Knob, Tone Control (BLK)
4822 411 10051 | Knob, Tone Control (GLD)
4822 410 60194 | Button, Power (BLK)
4822 410 60358 | Button, Power (GLD)
4822 410 60343 | Button, Speaker (BLK)
4822 410 60334 | Button, Speaker (GLD)
4822 466 92249:
4822 492 63973
Insulator
Spring (Q719)
4822 462 41477
4822 532 60948
Leg
Bushing, AC Cord
4822 253 30027
4822 253 30191
Fuse, T3.15A 250V [E]
Fuse, T1.6A 250V [E]
4822 256 30233
4822 264 30266
4822 290 40297
4822 272 10227 .
Jack, Fuse Holder [E]
Jack, AC Outlet [E]
Terminal, GND
Voltage Selector [E]
4822 146 21457
4822 146 21471
Power Transformer [A N, T, W]
Power Transformer [E]
4822 273 10194 Rotary Switch, Selector
4822 736 20422 | User Manual
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12 13
MARA-00480 / Druck 6

5. IDLING CURRENT ADJUSTMENT
(1) Before switching the power ON, set the Master Volume
~ control to the minimum position and the Balance and
Tone controls to the center positions. Also set semi-fixed
resistors R719 (L CH) and R720 (L CH) on PCB P7071 to
the center positions.
(2) Each of the cement resistors R743 (L CH) and R744 (R
CH) on the PCB P701 is provided with three test points.
Connect a digital voltmeter, set for the DC voltage input,
to the test points at the two extremities of the three
test points of R743 or R744.
(3) After the setup above, ‘switch the power ON and adjust
semi-fixed resistor R719 (L CH) or R720 (R CH) on
PCB P701 according to the digital voltmeter reading.
The target setting value is 14 mV (38.9 mA) for both the
L_ CH and R CH.
Please refer to the table below.
[amin amin |
Note on Safety:
Symbol A Fire or electrical shock hazard. Only original
parts should be used to replace any part marked with
Any other component substitution (other
symbol A .
than original type), may increase risk of fire or electrical
shock hazard.
6. HOW TO CHANGE THE SUPPLY VOLTAGE
(A/N/T/W Versions)
With the PM-50 A and T Versions, the rated supply voltage
of 240V can he changed to 220V. In the same way, the 220V
rated supply voltage of the PM-50 N and W Versions can be
changed to 240V.
Refer to the following diagram for the voltage change pro-
cedure.
FT
r IAL 7
Ler
J953 J952
AC CORD
wool
1?)
E
' J95!
io BD Zz
c
Te ae
io
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Soldered surface of P951
After binding solder around the terminal, bundle the
brown wire and blue wire together and tighten them with
a tightener.
@ Note on Terminals J951 and J956
Wrapping terminals J951 and J956 on the P951 PC board are
critical components for the safety. Please observe the follow-
ing caution when working these terminals.
7
Terminal side view
Wrapping shall be performed within range A .
When binding up solder, apply solder within range B .
14 MZ 2298

7. TEST EQUIPMENT REQUIRED FOR SERVICING <
This table lists the test equipment required for servicing the Model PM-55 Stereo Amplifier.
-Distortion measurements
Distortion Analyzer
Audio
Oscillator
Sinewave
and
squarewave
signal
source
ACVTVM Voltage measurements (AC) ,
— OO OO S|
Oscilloscope Waveform analysis.and trouble shooting and ASO aignment
Circuit Tester Trouble shooting . é
DCVTVM Voltage measurements (DC)
AC Wattmeter Monitors primary power to amplifier
Line Voltmeter Monitors potential of primary power to amplifier
Variable Autotransformer Adjust level of primery power to amplifier
Shorting Plug Shorts amplifier input to eliminate noise pickup
8. VOLTAGE CONVERSION
@ EUROPEAN MODEL ONLY ;
To convert the unit to a different power source voltage,
change the position as illustrated in the drawing below.
VOLTAGE SELECTOR
\
_
i
CAUTION
| DISCONNECT POWER SUPPLY CORD FROM AC
OUTLET BEFORE CONVERTING VOLTAGE.
MZ 2299 15