Onkyo CM 70 Service Manual

Page 1

C-M7O

Ref. No.3435
ONKYO® SERVICE MANUAL
COMPACT DISC PLAYER
Silver and Black models
UD. UDN. UDC, BHUD. BHUDN. BHUDC I20V AC. 60Hz
UP. UPV. UPF. BHUP. BHUPV. BHUPF 230V AC, SOHZ
UW, BHUW 120/220V AC, 50/60Hz
UQA, BHUQA 240V AC. 50Hz
SAFETY-RELATED COMPONENT WARNING SPECIFICATIONS
COMPONENTS IDENTIFIED BY MARK A ON THE Signal readout system: Optical non-contact
SCHEMATIC DIAGRAM AND IN THE PARTS LIST ARE Reading rotation: About 500~200 rip.m,
CRITICAL FOR RISK OF FIRE AND ELECTRIC SHOCKV (constant linear velocity)
REPLACE THESE COMPONENTS WITH ONKYO PARTS Linear velocity: l.2~1,4m/s
WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS Error correction system: Cross interleave readsolomon code
MANUAL D/A converter: 1 bit PWM
l f : 352.8kl-I 8 t l'
MAKE LEAKAGE-CURRENT 0R RESISTANCE MEA- :ZgIIJIeIIgofrigngS; 2 (Sims ""63 mam? mg)
SUREMENTS TO DETERMlNE THAT EXngED EAST: Frequency response: 5Hz~20kHz
ARE ACCEPTABLY INSULATED FROM E S P I Total harmonic distortion: 0,004% (at lkHz)
CIRCUIT BEFORE RETURNING THE APPLIANCE TO Dynamic range: 96dB
THE CUSTOMER Signal to noise ratio: 96dB
Channel separation: 90dB (at IkHz)
Wow and Flutter: Below threshold of measurability
Power consumption: 11 watts
Output level: 2 volts r.rn.s.

ONKYOQ l
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Dimensions (WXHXD): 275x115><304mm
10~13/16X4-9/I6"X 12
Weight: 42kg. 9.31bs.

Specifications are subject to change without notice,

Page 2

TABLE OF CONTENTS

Specifications ........................................ 1

Note on compact disc ........

Service procedures ..........
Protection of eyes from laser beam during servicing. ..3

Laser Iarning labels ................................... 3

Chassisiexploded vial ................
Parts list ................
Iicroprocessor connection vieI ....................... 6

IC block diagram and description .........

Printed circuit board vieI ...............

Schematic diagram ..................................... 15
Block diagram ...................................... 18
Printed circuit board parts list ................... l9
lechanisn-exploded viel ............................... 21
lechanistl parts list ................ 23

Adjustment procedures. . . 24

Packing vicI .............................

NOTE ON COMPACT DISC

0 Holding Compact Discs

Hold Compact Discs by the edges so that you do not touch
the surface of disc. Remember that the side ofthe disc with
the rainbow" reflection is the side containing the audio
information.

Do not attach tape or paper to the label side of the disc
and always be careful not to leave fingerprints on the side
that is played.

0 Storing Compact Discs

Store Compact Discs in a location protected from direct
sunlight, high heat and humidity and extremely high
and low temperatures Discs should never be left in the
trunk or interior of an automobile in the sun since the
temperature can become very high in such a closed environ-
ment.

Always store Compact Discs in the holders in which they
were sold. Never leave a disc in the players disc holder for
along period of time.

Not this waY

SERVICE PROCEDURES

1. S afety-check out
After correcting the original service problem.perform
the following safety check before releasing the set
to the customer:
Connect the insulating-resistance tester between the
plug of power supply cord and chassis.
SpecificationszMore than lOMohm at 500V.

2. Voltage Selector (B ack panel)
Worldwide models are equipped with a voltage selector
to conform with local power supplies.Be sure to set
this switch to match the voltage of the power supply
in user's area before turning the power switch on.
Voltage is changed by sliding the groove in the switch
with a screw driver to the tight or left.
Confirm that the switch has been moved all the way to
the right or left before turning the power switch on.

[11:] ElTl
4-L»

220V ~ lZOV N
at AC220V

<-

220V ~ 120V ~
at AC 1 20V

I Cleaning Compact Discs

Before playing a disc wipe off the playing surface with a
soft cloth to remove dust and other soil. Wipe the surface
in straight lines from the center of the disc outward. not
in a circular motion as you would with a phonograph
record.

Do not use benzene. chemical cleansers or phonograph
record cleaning solutions to clean Compact Discs. Also
avoid static electricity prevention solutions since they can
damage the surface of Compact Discs.

Problems Caused by Dew

Dew can form inside a Compact player when it is brought
from a cold environment into a warm room, when a room
is rapidly heated and if a player is left in a humid environ-
ment.

This dew can prevent the laser pickup from reading the
data contained in the pits in the disc surface. If the player
does not operate properly because of dew, remove the disc
and leave the player's power switch on for about one
hour to remove all moisture.

Page 21

C-M70

ADJUSTMENT PROCEDURES

Instruments required
Dual trace oscilloscope, Frequency counter, AF oscillator, Test disc (SONY YEDS-lS), AC voltmeter,

and Socket P4(Part no. 25050138)

1. Focus offset adjustment

Load the test disc YEDS-IS on the tray and play the track 2.
Connect the oscilloscope to terminal P l 06

Adjust R108 until RF waveform as shown photo 1
becomes maximum.

When the amount of RF Signal is broad, set R I 08 to
mechanical center.

I gun Oscilloscope range
Vertical : 0.5V/div.
2 Oscilloscope Holizontal : 0,2 its/div.
! 'tbcfinlaar, ' . . __ + DC, Ground: Center
e o 6 . . y . . l 3
13" 5 .' 3 w z s 4
total 5
6
2. Tracking offset adjustment
Load the testdisc YEDS-18 on the tray and play the track 2.
Turn Rl IS to minimum position.(Counter clockwise)
Connect the oscilloscope between pin 5 (TR) of P106 and
pin 1 (GND)
Adjust RIQS until the center of tracking error signal on
the oscilloscope becomes GND level.
Tum R115 to the mechanical center.
After adjustment, disconnect the oscilloscope.
6
__ 5 .
A 4 Oscnllosoope
- GND level
B 3
- A:B 2 Vertical :500mV/div.
Holizontal : 1 ms/div.
- I DC, Ground: Center
F 2 9ND

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