Sony hcd gx 450 service manual

Page 1

HCD-GX450

SERVICE MANUAL

Ver. 1.2 2005.08

- HCD-GX450 is the tuner, deck, CD and
amplifier section in MHC-GX450.

US Model
Canadian Model

Former Type Models New Type Models
Model Name Using Similar Mechanism New New
CD _ CD Mechanism Type CDM74-F1BD81 CDM74KF-K6BD81C
Sectlon Optical Pick-up Name KSM-215DCP/02NP KSM-213DCP/C2NF
Tape deck Model Name Using Similar Mechanism New New
Section Tape Transport Mechanism Type CWM43FF-05 CWM43FF-05

SPECIFICATIONS

Amplifier section

AUDIO POWER SPECIFICATIONS Laser
POWER OUTPUT AND TOTAL HAFIMONIC
DISTORTION:

With 6 ohm loads, both channels driven, from
120 7 10,000 Hz: rated 125 watts per channel
minimum RMS power, with no more than 10%
total harmonic distortion from 250 milliwatts to
rated output.
Front speaker
Continuous RMS power output (reference):
125 + 125 watts (6 ohms at
1 kHz, 10% THD)
Total harmonic distortion less than 0.07% (6 ohms at
1 kHz, 60 W)

Frequency response
Wavelength
Signalrtornotse ratio
Dynamic range

Tape deck section

Recording system
Frequency response

Sub woofer Tuner section

Continuous RMS power orrtput (reference):

150 watts (6 ohms at

50 Hz, 10% THD)

less than 0.07% (6 ohms at
50 Hz, 75 W)

FM tuner section
Tuning range
Total harmonic distortion
Antenna

Antenna terminals

CD player section Intermediate frequency

System Compact disc and digital
audio system
9-877-534-03 Sony Corporation
2005H1 6-1 Personal Audio Group
© 2005.08 Published by Sony Engineering Corporation

Semiconductor laser
(1.2780 nm)

Emission duration:
continuous

2 Hz 7 20 kHz (10.5 dB)
780 , 790 nm

More than 90 (113

More than 90 dB

4rlrack Zechanncl. stereo
50 713000 Hz (:3 (113),
using Sony TYPEI

c _ , ettcs

FM stereo. FM/AM superheterodyne tuner

87.5 , 108.0 MHz
(IOOVkHL step)

FM lead antenna

75 ohms unbalanced
10.7 MHZ

AM tuner section
Tuning range 530 7 1,710 kHz
(with the tuning interval
set at 10 kHz)

531 , 1,710 kHz

(with the tuning interval
set at 9 kHz)

Antenna
Antenna terminals

AM loop antenna
External antenna terminal
Intermediate frequency 450 kHL

General
Power requirements 120 V AC, 60 BL
Pow er consumption
USA mode

Canadian models:

265 watts

330 VA

Dirnerr "ons (w/h/d) rncl. projecting parts and controls
Arnplil'ier/Tuner/Tape/CD section:

Approx. 280 x 327 x

425 mm

Approx. 10.0 kg

Mass

Design and specifications are subject to change
without notice.

MINI Hl-Fl COMPONENT SYSTEM
S ONYC;

Page 2

HCD-GX450

SAFETY CHECK-OUT

After correcting the original service problem, perform the
following safety checks before releasing the set to the customer:
Check the antenna terminals, metal trim, metallized knobs, screws,
and all other exposed metal pans for AC leakage. Check leakage as
described below.

LEAKAGE

The AC leakage from any exposed metal part to earth ground
and from all exposed metal parts to any exposed metal part having
a return to chas s, most not exceed 0.5 mA (500 microamperes).
Leakage current can be measured by any one of three methods.

l. A commercial leakage tester, such as the Simpson 229 or RCA
WT7540A. Follow the manufacturers instructions to use these
instruments.

2. A battery-operated AC milliammeter. The Data Precision 245
digital multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by means of a
VOM or battery-operated AC voltmeter. The limit" indication
is 0.75 V, so analog meters must have an accurate low-voltage
scale. The Simpson 250 and Sanwa SH-63Trd are examples of
a passive VOM that is suitable. Nearly all battery operated
digital multimeters that have a 2V AC range are suitable. (See
Fig. A)

To Exposed Metal
Paris on Set
AC
0.15uF:: :15) zigzag
5 Earth Ground

Fig. A. Using an AC voltmeter to check AC leakage.

SAFETY-RELATED COMPONENT WARNING !!

COMPONENTS IDENTIFIED BY MARKA OR DOTTED LINEWITH
MARK A ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS
LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE
COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS
APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS
PUBLISHED BY SONY.

ATTENTION AU COMPOSANT AYANT RAPPORT
A LA sEcuanE!

LES COMPOSANTS IDENTIFES PAR UNE MAROUE A SUR LES
DIAGRAMMES SOHEMATIOUES ET LA LISTE DES PIECES SONT
CRITIQUES POUR LA SECURITE DE FONCTIONNEMENT. NE
REMPLACER CES COMPOSANTS OUE PAR DES PIESES SONY
DONT LES NUMEPOS SONT DONNES DANS CE MANUEL ou
DANS LES SUPPEMENTS PUBLIES PAR SONv.

2

The release method of a CD disc tray LOCK function

There is a disc lock function for the disc theft prevention for a

demonstration at a shop front in this machine.

Procedue:

1. Press the I button to turn the set on.

2. Press two buttons oflil and simultaneously for
five seconds.

3. The message LOCKED is displayed and the tray is locked.
(Even if exiting from this mode, the tray is still locked.)

4. Press two buttons oflil and simultaneously for
five seconds again.

5. The message UNLOCKED is displayed and the tray is
unlocked.

6. To exit from this mode, press the _ button to turn the set
off.

Unleaded solder

Boards requiring use of unleaded solder are printed with the lead
free mark (LF) indicating the solder contains no lead.

(Caution: Some printed circuit boards may not come printed with
the lead free mark due to their particular size.)

I
1'- LEAD FREE MARK
Unleaded solder has the following characteristics.

- Unleaded solder melts at a temperature about 40°C higher than
ordinary solder.

Ordinary soldering irons can be used but the iron tip has to be
applied to the solderjoint for a slightly longer time.

Soldering irons using a temperature regulator should be set to
about 350°C.

Caution: The printed pattern (copper foil) may peel away if the
heated tip is applied for too long, so be careful!

Strong viscosity

Unleaded solder is more viscous (sticky, less prone to flow) than
ordinary solder so use caution not to let solder bridges occur such
as on IC pins, etc.

Usable with ordinary solder

It is best to use only unleaded solder but unleaded solder may
also be added to ordinary solder.