Onkyo DX 320 Service Manual

Page 1

DX-3 0

SERIAL NO. 3229

ONKYO® SERVICE MANUAL

COMPACT DISC PLAYER
MODEL DX-320

I BUDN. BUD 120V AC. 60Hz
I BUG 220V AC, SOHZ
I BUW, BUWX I 120/220V AC, 50/60Hz
I BUQA 240V AC, SOHZ
SAFETY-RELATED COMPONENT WARNING SPECIFICATIONS
COMPONENTS IDENTIFIED BY MARK A ON THE Type: Compact Disc player with
SCHEMATIC DIAGRAM AND IN THE PARTS LIST ARE optical pickup
CRITICAL FOR RISK OF FIRE AND ELECTRIC SHOCK. Quantization: 16 bit linear
REPLACE THESE COMPONENTS WITH ONKYO PARTS Channels: 2 (Stereo)
WHOSE PARTS NUMBERS APPEAR AS SHOWN IN THIS Frequency response. 2H2 "' ZOkHz i0.5dB
MANUAL. Dynamic range: 96dB
Total harmonic distortion.0.003% (lkHz)
MAKE LEAKAGE-CURRENT OR RESISTANCE MEA- Channel separation. 93dB
SUREMENTS TO DETERMINE THAT EXPOSED PARTS S/N ratio; 96d];
ARE ACCEPTABLY INSULATED FROM THE SUPPLY Wow and flutter: Unmeasurable
CIRCUIT BEFORE RETURNING THE APPLIANCE TO Output: 2.0 volts
THE CUSTOMER Pickup: Semiconductor lasei type
Power consumption: 22 watts
Dimensions: 435(W) x 92(H) x 357(D) mm
17-1/8" x 3-5/8 x 14-1/16
Weight: 5.8kg. 12.81bs.
Accessories: Connection cables

Instruciion manual
Remote control

Specifications are subject to change without notice.
,K 7 - fl
ONKYO .
!

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DX-320

TABLE OF CONTENTS

Specifications ............................ 1
Precautions ..............................

Notes on compact disc ....................... 3
Protection of eyes from laser beam .............. 4
Laser warning labels ........................ 4
Cautions on replacement of pick-up .............. 6
Packing view ............................. 7
Chassis exploded view ....................... 8
Parts list ................................ 9
Mechanism exploded view ................... 10
Parts list ............................... 1 1
Flow chart of operation ..................... 12
Circuit description ........................ 16
Block diagram ........................... 25
Block diagram of ICS ....................... 26
Adjustment procedures ..................... 32
Printed circuit board view/Parts list ............. 35

PRECAUTIONS

l, Removing the Transport Screws and Locking Plate
Three transport screws and locking plate are located on
the bottom panel of this unit, Before using this unit for
the first time, these screws and the plate must be removed.
If power is switched on while thes parts are still in place,
the unit will not operate properly.

1. Locking plate
2/4. Transport screws 2

3. Spacers / l
I

Fig. 1

2. Safety-check out (USA. model)

After correcting the original service problem, perform the
following safety check before releasing the set to the
CUSIOUICIZ

Connect the insulating-resistance tester between the plug
of power supply cable and chassis.

Specifications: more than lOMohm at 500V.

3. Procedures for replacement of flat packaged ICs
1. Tools to be used:
(I) Soldering iron . Grounded soldering iron or
soldering iron with leak re-
sistance of 10 Mohms or
TOTE.

Form oi~ soldering irons tip:

E: H, 2

(2) Magnifying glass . .. for checking of finished

works

(3) Tweezers ........ for handling of IC and
forming of leads

(4) Grounding ring. . . . Countermeasure for electro-
static breakdown

(5) Nipper ......... for removing defective [C

(6) Small brush ...... for application of flux

2. Work Procedures;

(1] Remove the defective lC
Cut all leads of the defective 1C one by one using
a nipper and remove the 1C.

(2) Clean the pattern surface of the PC board.
Get rid of the remaining leads and solder

(3) Check and from the leads of the new Flat pack-
aged IC to be installed.
From every lead on the new [C using a pair of
tweezers, so that all of them are aligned neatly
without being risen, twisted or inclined toward
one side. Especially the rising portion of every
lead must be formed with greatest care.

It: IC // IC /
\\/" Egg //
(Rismgl (Twisting) (inclining)
Fig. 3

(4) Apply flux to the PC board.

Apply flux to the pattern surface of the PC board
which has been cleaned, as shown in the illustration.
The area to be applied with flux is the portion of
about 2.5mm in width where the ICs leads are to
be soldered,

Be careful to apply minimum amount of flux
required so as not to smear it on unwanted areas,

About 2.5 mm

Fig. 4

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DX-320

10.4 Mechanical and Other Control Systems

(1) Laser On/Off

Optical pick-up laser on/off control output.
when the output is at low level.

Laser is on

(2) Muting Terminal

Audio muting control output for audio muting when the
disc is stopped, and during accessing opertions and pause
mode. Muting is applied when the output is at high level.

(3) Emphasis Terminal

Automatic detection of disc pre~emphasis, and output of
the audio decmphasis control signal. Emphasis is switched
on when the output is at high level.

(4) Sub-code Decoding

Decoding of sub-code data (apart from audio data) retriev-
ed from the disc. These sub-codes include tracking
numbers, index numbers, play time, total time, emphasis
on/off, and the inter-tune signal. The inputs are listed
below

SUBQ (pin 39) . . . Sub-code Q signal serial data input.
Data is shifted at WFCK trailing edges, and read by the
microcomputer at leading edges.

WFCK (pin 41) . . SUBQ data shift clock.
when the PLL is locked.

SBSO (pin 2) . . . . Subicode P signal output. High when
between tunes.

7.3SkHz

SCOR(p1n 35) . . . Subcode sink code output. 75H:
when PLL is locked.
CRCF (pin 1) . . . SUBQ input CRC checker pin. High

level if SUBQ input data contains no errori

(5) Reset Circuit

Using an IC designed specifically for microcomputer
resetting, a reset output (low level) is applied to the
micrOCOmputer RST terminal (pin 33) when +5V line
voltage drops below the 4V reference voltage.

This pm is normally switched to low level temporarily
when the power is switched on, and is subsequently kept
at high leveli

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Fig. 32

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Fig. 33

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RST
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Fig. 34

Fm.35

(6) Clock Circuit

The microcomputer clock (4.23MH2) signal source is the
over sampling filter (Q202). The clock is passed to the
Processor (0201). The clock is passed to the microcompu-
ter via the route outlined in Fig. 35. if a failure occurs at
any point along this route, system operation will come to
a complete halt.