Onkyo M 5060 Service Manual

Page 1

3175060
SERIAL NO. 3084

ONIKYO® SERVICE MANUAL

DUAL SUPER SERVO
STEREO POWER AMPLIFIER
MODEL M-506O

TABLE OF CONTENTS

Item

5;?

Specifications
Features

Block diagram
Circuit description
Adjustment
Connection diagram
Component location
Precautions
Exploded View
Schematic diagram
Printed circuit board view
Packing procedures

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(75060

SPECIFICATIONS
D Model
Power Output: 120 watts per channel, min. RMS, at

Total Harmonic
Distortion:

lntermodulation
Distortion:

Frequency Response:

Input Sensitivity:
Input Impedance:
Damping Factor:

Signal to Noise Ratio:
Power Supply Rating:

Outputs:

Inputs:
Semiconductors:
Dimensions:

Weight:

8 ohms both channels driven, from
20 Hz to 20 kHz, with no more than
0.005% total harmonic distortion.
0.005% at Rated power

0.005% at 1 watt output

0.005% at Rated power

+0, -1.5 dB at 1 Hz ~ 100 kHz

1.5 V

47 k9

140 (8 Q, 1 kHz)

94 dB (IHF A202)

AC120 V 60 Hz

SPEAKERS 1 8i 2, AC OUTLET, PHONES
INPUT P

2 FETs, 47 Transistors. 40 Diodes, 6 ICS
450 (W) x 174 (H) x400 (D) mm
(17-3/ x 6-7/ "x 15-3/ ")

17.8 kg (39.2 lbs.)

Specifications and features are subject to change without notice.

FEATURES

1. Dual Super-Servo System

G Model
Power Output:

Total Harmonic
Distortion:
lntermodulation
Distortion:

Frequency Response:

Input Sensitivity:
Input Impedance:
Damping Factor

Signal to Noise Ratio:
Power Supply Rating:

Outputs:

Inputs:
Semiconductors:
Dimensions:

Weight:

120 watts per channel, min RMS, at
8 ohms both channels driven, from
20 HZ to 20 kHz, with no more than
0.005% total harmonic distortion.
0.005% at Rated power

0.005% at 1 watt output

0.005% at Rated power

+0, -l.5 dB at 1 Hz~ 100 kHz
1.5 V

47 k9

140 (8 9,1 kHz)

94 dB (IHF A-202)

AC220 V 50 Hz

SPEAKERSl 8i 2, PHONES
INPUT P.

2 FETs, 47 Transistors, 4O Diodes, 6 ICS
450 (W) x 174 (H) x 400 (D) mrn
(17-3/4"x 6-7/8" x 15-3/4)
17.8 kg (39.2 lbs.)

Specifications and features are subject to change without notice.

Adapting the present super-servo to dual system has made control of the total positive and negative signal path pos-
sible, thereby cutting out a number of internally generated distortion sources. Power supply and ground source
distortion has been reduced and improvement has been particularly dramatic in the power amp where distortion has a
pronounced effect on tonal quality.

2. Linear Switching System
Linear switching is used in the output stage of the power amp. Operationally this is the most simple method and
produces the best results. Also, using a high FT (cut-off frequency) transistor has completely eliminated switching
distortion improving sound purity.

3. High Quality and High Power
Based on monaural construction, 120 watts per channel with 0.003% distortion at rated output. Starting with the
dual super-servo, the most advanced technology available writes new standards for music reproduction.

4. Quick Responding, Large Peak Meters
Large, quick response dual level meters with 65mm needles have been selected for the M-5060. These meters work in
conjunction with the transient killer circuit and protection circuit, providing a means to monitor operation. Power
meter illumination is also featured.

5. Dual Super-Servo System Power Section
This unit forms the power section for the P73060 Dual Super-Servo amp system. This combination maximizes all the
advantages of the total system. Naturally, it may be used with other preamps and still retain all the merits inherent in
its dual super-servo design.

6. Dual Power Supply - Dual Monaural Amp Construction
Two large power supplies constructed using parts selected under the most critical criteria help maintain musical
purity.

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75060

ADJUSTMENTS

1. Preparations
(1) When making adjustments, lower the pedestals of the unit and set it
on a level bench. Make sure a space of at least 15 mm exists between the
bench and the bottom of the unit for ventilation.
(2) Place the unit at lowest level, no load, and no signal.
(3) During adjustment, any drafts in the room will cause unstable read-
mgs.

2. Adjusting the meter to ZERO
(1) With the power supply OFF, adjust the screw on the lower part of
the meter until the needle is on 0.
(2) Do not make this adjustment immediately after turning OFF the
power supply. Wait until the meter circuit has discharged.

3. Adjusting idling current
(1) Remove the cover. Tum ON the power supply to obtain voltage
between VCT and IID of board NAMA-752. After waiting 5 minutes, 1009 each
adjust VR R4039 (R4040) until a reading of 12 my is obtained. (After DC VW- emitter
20 minutes of stabilization, the reading should be 16 mV.)
(2) After the above adjustment is completed, make certain the voltage
reading between VCT and the emitters of Q4025 (Q4026), Q4029
(Q4030), and Q4031 (Q4032) is approximately the same. When making
this test, use a 100 $2 resistance between the testing device and emitter as
shown in the drawing at right.

Volt meter
--> Vcr

4. Adjusting meter offset
After the power supply switch is ON, wait 5 minutes and without signal
input, adjust OFFSET VR R1040 (R1041) on board NAME-758 to the
point the meter reads 0.

5. Meter level adjustment

Apply a 1 kHz test signal to the INPUT terminal of the left channel and
set the M-5060 meter ranging switch to X 0.1. Adjust input to the
point the voltage reading (no load) at the speaker output is 9.8 V (19.82
dBV), and adjust LEVEL VR R1014 (R1015) on board NAME~758
until the meter reads 0. Adjust the right channel the same way. 030 not
apply signals to the right and left channel simultaneously.)

NOTE: The numbered transistors and variable resistors in paranthesis
( ) apply to the right channel.

more 1° mou H1040

no

Power amp. p.c.b Meter circuit peb.
Adjustment point