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 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 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

Parts on Set

 

 

 

 

 

 

 

 

AC

 

 

 

 

 

 

 

 

0.15 F

 

 

 

1.5 kΩ

 

 

Voltmeter

 

 

 

 

 

 

 

 

 

 

(0.75 V)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Earth Ground

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

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY MARK 0OR DOTTED LINE WITH MARK 0ON 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.

TABLE OF CONTENTS

1.GENERAL ·························

2.TEST MODE ························

3.DIAGRAMS

3-1. Block Diagram ······················

3-2. IC Block Diagrams ····················

3-3. IC Pin Function Description ················

3-4. Circuit Boards Location ··················

3-5. Printed Wiring Board Main Section ·············

3-6. Schematic Diagram Main Section (1/3) ···········

3-7.

Schematic Diagram

Main Section (2/3) ···········

3-8.

Schematic Diagram

Main Section (3/3) ···········

3-9.

Printed Wiring Board

Panel Section ·············

3-10. Schematic Diagram

Panel Section ·············

3-11. Printed Wiring Board

Power Section ············

3-12. Schematic Diagram

Power Section ············

3-13. Printed Wiring Board

Video Section ············

3-14. Schematic Diagram

Video Section ·············

4.EXPLODED VIEWS

4-1. Front Panel Section ····················

4-2. Chassis Section ······················

5.ELECTRICAL PARTS LIST ················

ATTENTION AU COMPOSANT AYANT RAPPORT À LA SÉCURITÉ!

LES COMPOSANTS IDENTIFÉS PAR UNE MARQUE 0SUR LES

DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE REMPLACER CES COMPOSANTS QUE PAR DES PIÈSES SONY DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU DANS LES SUPPÉMENTS PUBLIÉS PAR SONY.

3

Page 3
Image 3
Sony STR-DE245/DE345 specifications Safety CHECK-OUT, Leakage, Table of Contents, Diagrams, Exploded Views