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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.
After correcting the original service problem, perform the
following safety checks before releasing the set to the customer:
Check the antenna terminals, metal trim, ÒmetallizedÓ knobs, screws,
and all other exposed metal parts 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 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 manufacturersÕ 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 ÒlimitÓ 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)
SAFETY CHECK-OUT
To Exposed Metal
Parts on Set
0.15
µF
1.5 k ½
AC
Voltmeter
(0.75 V)
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
ATTENTION AU COMPOSANT AYANT RAPPORT
Ë LA SƒCURITƒ!
LES COMPOSANTS IDENTIFƒS PAR UNE MARQUE 0 SUR LES
DIAGRAMMES SCHƒMATIQUES ET LA LISTE DES PIéCES SONT
CRITIQUES POUR LA SƒCURITƒ DE FONCTIONNEMENT. NE
REMPLACER CES COMPOSANTS QUE PAR DES PIéSES SONY
DONT LES NUMƒROS SONT DONNƒS DANS CE MANUEL OU
DANS LES SUPPƒMENTS PUBLIƒS PAR SONY.
TABLE OF CONTENTS
1. GENERAL
ááááááááááááááááááááááááááááááááááááááááááááááááááá\
ááááááááááááááááááááááá 4
2. TEST MODE ááááááááááááááááááááááááááááááááááááááááááááááááááá\
ááááááááááááááááááá 6
3. DIAGRAMS
3-1. Block Diagram ááááááááááááááááááááááááááááááááááááááááááááááááááá\
ááááááááááá 7
3-2. IC Block Diagrams ááááááááááááááááááááááááááááááááááááááááááááááááááá\
ááááá 8
3-3. IC Pin Function Description áááááááááááááááááááááááááááááááááááááááááá 8
3-4. Circuit Boards Location áááááááááááááááááááááááááááááááááááááááááááááááá 9
3-5. Printed Wiring Board Main Section áááááááááááááááááááááááááá 10
3-6. Schematic Diagram Main Section (1/3) áááááááááááááááááááá 11
3-7. Schematic Diagram Main Section (2/3) áááááááááááááááááááá 12
3-8. Schematic Diagram Main Section (3/3) áááááááááááááááááááá 13
3-9. Printed Wiring Board Panel Section áááááááááááááááááááááááááá 14
3-10. Schematic Diagram Panel Section ááááááááááááááááááááááááááá 15
3-11. Printed Wiring Board Power Section áááááááááááááááááááááááá 16
3-12. Schematic Diagram Power Section áááááááááááááááááááááááááá 17
3-13. Printed Wiring Board Video Section ááááááááááááááááááááááááá 18
3-14. Schematic Diagram Video Section ááááááááááááááááááááááááááá 18
4. EXPLODED VIEWS
4-1. Front Panel Section ááááááááááááááááááááááááááááááááááááááááááááááááááá\
áá 19
4-2. Chassis Section ááááááááááááááááááááááááááááááááááááááááááááááááááá\
ááááááááá 20
5. ELECTRICAL PARTS LIST ááááááááááááááááááááááááááááááááááááááá 21
