CD-C491H (serv.man4) - Sharp Audio Service Manual (repair manual)

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Page

SAFETY PRECAUTION FOR SERVICE MANUAL ...........................................................................................................  2
IMPORTANT SERVICE NOTES (FOR UK ONLY) ............................................................................................................  2
SPECIFICATIONS .............................................................................................................................................................  3
NAMES OF PARTS ...........................................................................................................................................................  4
OPERATION MANUAL ......................................................................................................................................................  7
QUICK GUIDE ...................................................................................................................................................................  8
DISASSEMBLY ................................................................................................................................................................  12
REMOVING AND REINSTALLING THE MAIN PARTS ...................................................................................................  15
ADJUSTMENT .................................................................................................................................................................  16
NOTES ON SCHEMATIC DIAGRAM ..............................................................................................................................  22
TYPES OF TRANSISTOR ................................................................................................................................................ 22
WAVEFORMS OF CD CIRCUIT ......................................................................................................................................  23
BLOCK DIAGRAM ...........................................................................................................................................................  28
SCHEMATIC DIAGRAM / WIRING SIDE OF P.W.BOARD .............................................................................................  57
TROUBLESHOOTING .....................................................................................................................................................  58
FUNCTION TABLE OF IC ................................................................................................................................................  62
FL DISPLAY .....................................................................................................................................................................  73
WIRING OF PRIMARILY SUPPLY LEADS (FOR UK ONLY) ..........................................................................................  74
REPLACEMENT PARTS LIST/EXPLODED VIEW
PACKING METHOD (FOR UK ONLY)

• In the interests of user-safety the set should be restored to its

original condition and only parts identical to those specified be
used.

Recording and playback of any material may require consent
which SHARP is unable to give. Please refer particularly to the
provisions of Copyright Act 1956, the Dramatic and Musical
Prefomers Protection Act 1956, the Preformers Protection Acts
1963 and 1972 and to any subsequent statutory enactments and
orders.

Manufactured under license from Dolby Laboratories.
"Dolby", "Pro Logic" and the double-D symbol are trademarks
of Dolby Laboratories. Confidential Unpublished Works.
©1992-1997 Dolby Laboratories, Inc. All rights reserved.

●

QSOUND and the QLogo are registered trademarks of
QSound Labs, Inc.

●

QSound is protected under US Patent Nos. 5,105,462 and
5,208,860 and foreign counterparts.

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The AEL (Accessible Emission Level) of Laser Power Output
for this model is specified to be lower than Class I Requirements.
However, the following precautions must be observed during
servicing to protect your eyes against exposure to the Laser
beam.

(1) When the cabinet has been removed, the power is turned

on without a compact disc, and the Pickup is on a position
outer than the lead-in position, the Laser will light for several
seconds to detect a disc. Do not look into the Pickup Lens.

(2) The Laser Power Output of the Pickup inside the unit and

replacement service parts have already been adjusted prior
to shipping.

(3) No adjustment to the Laser Power should be attempted

when replacing or servicing the Pickup.

(4) Under no circumstances look directly into the Pickup Lens

at any time.

(5) CAUTION - Use of controls or adjustments, or performance

of procedures other than those specified herein may result
in hazardous radiation exposure.

Before returning the unit to the customer after completion of a
repair or adjustment it is necessary for the following withstand
voltage test to be applied to ensure the unit is safe for the
customer to use.
Setting of Withstanding Voltage Tester and set.

Set name

set value

Withstanding Voltage Tester

Test voltage

4,240 VPEAK
3,000 VRMS

Set time

6 secs

Set current(Cutoff current)

4 mA

Unit

Judgment

OK: The “GOOD” lamp lights.
NG: The “NG” lamp lights and the buzzor sounds.

SHORT-CIRCUIT
AC POWER 
SUPPLY CORD

CONNECT THE PROBE
TO GND TERMINAL
OF PHONO TERMINAL 

 PROBE

AC

UNIT

WITHSTANDING
VOLTAGE TESTER

+

-

OUT

OF CHASSIS

SCREW

LASER KLASSE 1

LUOKAN 1 LASERLAITE

KLASS 1 LASERAPPARAT

CAUTION-INVISIBLE  LASER  RADIATION  WHEN  OPEN.  DO  NOT  STARE  INTO 
BEAM  OR  VIEW  DIRECTLY  WITH  OPTICAL  INSTRUMENTS.

VARNING-OSYNLIG  LASERSTRALNING  NAR  DENNA  DEL  AR  OPPNAD.  STIRRA
EJ  IN  I  STRALEN  OCH  BETRAKTA  EJ  STRALEN   MED  OPTISKA  INSTRUMENT.

ADVERSEL-USYNLIG  LASERSTRALING  VED  ABNING.  SE  IKKE  IND  I 
STRALEN-HELLER  IKKE  MED  OPTISKE  INSTRUMENTER.

VARO!  AVATTAESSA  OLET  ALTTIINA  NAKYMATON  LASERSATEILYLLE.
ALA  TUIJOTA  SATEESEEN  ALAKA  KATSO  SITA  OPTISEN  LAITTEEN  LAPI.

VARNING-OSYNLIG  LASERSTRALNING  NAR  DENNA  DEL  AR  OPPNAD.
STIRRA  EJ IN  I  STRALEN  OCH  BETRAKTA  EJ  STRALEN  GENOM  OPTISKT  
INSTRUMENT.

ADVERSEL-USYNLIG  LASERSTRALING  NAR  DEKSEL  APNES.  STIRR IKKE  
INN  I  STRALEN  ELLER  SE  DIREKTE  MED  OPTISKE  INSTRUMENTER.

Laser Diode Properties

Material: GaAIAs
Wavelength: 780 nm
Emission Duration: continuous
Laser Output: max. 0.6 mW

CHASSIS
SCREW

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AC 230 V, 50 Hz

190 W

Width; 270 mm (10-5/8")
Height; 316 mm (12-1/2")
Depth; 343 mm (13-1/2")

10.5 kg (23.2 lbs.)

Front speakers;
PMPO; 852 W (total)
MPO;

142 W (71 W + 71 W)
(DIN 45 324)

RMS:

80 W (40 W + 40 W)
(DIN 45 324)

Centre speaker;
MPO;

71 W
(DIN 45 324)

RMS:

40 W
(DIN 45 324)

Surround speakers;
MPO;

142 W (71 W + 71 W)
(DIN 45 324)

RMS:

80 W (40 W + 40 W)
(DIN 45 324)

Sub woofer;
MPO;

71 W
(DIN 45 324)

RMS:

40 W
(DIN 45 324)

Front speakers; 8 ohms
Centre speaker; 8 ohms
Surround speakers; 8 ohms
Sub woofer; 8 ohms
Monitor; 1 Vp-p/75 ohms
Headphones; 16 - 50 ohms
(recommended; 32 ohms)

DVD 1 (Digital); Optical
DVD 2 (Digital); Coaxial
VCR 1/AUX 1; 500 mV/47 kohms
VCR 2/AUX 2; 500 mV/47 kohms
DVD 1/VCR 1; 1 Vp-p/75 ohms
DVD 2/VCR 2; 1 Vp-p/75 ohms

FM; 87.5 - 108 MHz
MW; 522 - 1,620 kHz
LW; 153 - 281 kHz

50 - 14,000 Hz (Normal tape)

55 dB (TAPE 1, playback)
50 dB (TAPE 2, recording/

playback)

0.2 % (DIN 45 511)

3-disc multi-play compact disc
player

Non-contact, 3-beam semi-
conductor laser pickup

1-bit D/A converter

20 - 20,000 Hz

100 dB (1 kHz)

3-way, 130 mm (5-1/8") woofer,
50 mm (2") tweeter and super
tweeter

Maximum input power: 80 W
Impedance:

8 ohms

Width; 220 mm (8-11/16")
Height; 316 mm (12-1/2")
Depth; 284 mm (11-3/16")

3.4 kg (7.5 lbs.)/each

2-way, 120 mm (4-3/4") woofer
and 50 mm (2") tweeter

Maximum input power: 80 W
Impedance:

8 ohms

Width; 270 mm (10-5/8")
Height; 142 mm (5-5/8")
Depth; 220 mm (8-11/16")

1.8 kg (4.0 lbs.)

2-way, 100 mm (4") woofer and
50 mm (2") tweeter

Maximum input power: 80 W
Impedance:

8 ohms

Width; 200 mm (7-7/8")
Height; 134 mm (5-5/16")
Depth; 240 mm (9-1/2")

1.4 kg (3.1 lbs.)/each

160 mm (6-1/2") woofer

Maximum input power: 80 W
Impedance:

8 ohms

Width; 220 mm (8-11/16")
Height; 316 mm (12-1/2")
Depth; 294 mm (11-5/8")

3.8 kg (8.4 lbs.)

FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE REFER
TO THE OPERATION MANUAL.

Specifications for this model are subject to change without
prior notice.

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