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GTK-XB90
2
SAFETY-RELATED COMPONENT WARNING!
COMPONENTS IDENTIFIED BY MARK
0
OR DOTTED LINE
WITH MARK
0
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
À LA SÉCURITÉ!
LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE
0
SUR
LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES
PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE FONC-
TIONNEMENT. NE REMPLACER CES COMPOSANTS QUE
PAR DES PIÈCES SONY DONT LES NUMÉROS SONT DON-
NÉS DANS CE MANUEL OU DANS LES SUPPLÉMENTS
PUBLIÉS PAR SONY.
License and Trademark
Notice
t
MPEG Layer-3 audio coding
technology and patents licensed
from Fraunhofer IIS and Thomson.
t
Windows Media is either a registered
trademark or trademark of Microsoft
Corporation in the United States
and/or other countries.
t
This product is protected by
certain intellectual property rights
of Microsoft Corporation. Use or
distribution of such technology
outside of this product is prohibited
without a license from Microsoft or
an authorized Microsoft subsidiary.
t
The BLUETOOTH® word mark and
logos are registered trademarks
owned by Bluetooth SIG, Inc. and
any use of such marks by Sony
Corporation is under license. Other
trademarks and trade names are
those of their respective owners.
t
The N-Mark is a trademark or
registered trademark of NFC Forum,
Inc. in the United States and in other
countries.
t
Google Play and Android are
trademarks of Google Inc.
t
LD AC™ and LDAC logo are
trademarks of Sony Corporation.
t
Apple , the Apple logo, iPhone, and
iPod touch are trademarks of Apple
Inc., registered in the U.S. and other
countries. App Store is a service
mark of Apple Inc.
t
“Made for iPod” and “Made for
iPhone” mean that an electronic
accessory has been designed to
connect specifically to iPod or
iPhone, respectively, and has been
certified by the developer to meet
Apple performance standards. Apple
is not responsible for the operation
of this device or its compliance with
safety and regulatory standards.
Please note that the use of this
accessory with iPod or iPhone may
affect wireless performance.
t
WALKMAN and WALKMAN logo
are registered trademarks of Sony
Corporation.
t
All other trademarks and registered
trademarks are of their respective
holders. In this manual,
TM
and
®
marks are not specified.
SAFETY CHECK-OUT
After correcting the original service problem, perform the follow-
ing safety check before releasing the set to the customer:
Check the antenna terminals, metal trim, “metallized” knobs,
screws, and all other exposed metal parts for AC leakage.
Check leakage as described below.
LEAKAGE TEST
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 chassis, must not exceed 0.5 mA (500 microamperes.).
Leakage current can be measured by any one of three methods.
1. A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. 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 2 V AC range are suitable. (See
Fig. A)
1.5 k
Ω
0.15
μ
F
AC
voltmeter
(0.75 V)
To Exposed Metal
Parts on Set
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
SYS SET
2020/08/20 22:42:53 (GMT+09:00)