Sony SA-WM200, Service Manual

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2
SA-WM200
Specifications ........................................................................... 1
1. GENERAL
...................................................................... 3
2. DIAGRAMS
2-1. Circuit Boards Location ............................................. 3
2-2. Printed Wiring Boards – Main Section – .................... 4
2-3. Printed Wiring Boards – Input Control Section – ....... 5
2-4. Printed Wiring Boards – Power Section – .................. 6
2-5. Schematic Diagram – Main Section (1/2) – ............... 7
2-6. Schematic Diagram – Main Section (2/2) – ............... 8
3. EXPLODED VIEWS
3-1. Main Section ............................................................... 9
4. ELECTRICAL PARTS LIST
................................... 10
TABLE OF CONTENTS SAFETY CHECK-OUT
(US model)
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
microampers). 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)
Fig. A. Using an AC voltmeter to check AC leakage.
0.15 µ F
To Exposed Metal
Parts on Set
1.5k Ω
AC
voltmeter
(0.75V)
Earth Ground
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 PUB-
LISHED 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
FONCTIONNEMENT. NE REMPLACER CES COMPOSANTS
QUE PAR DES PIÈCES SONY DONT LES NUMÉROS SONT
DONNÉS DANS CE MANUEL OU DANS LES SUPPLÉMENTS
PUBLIÉS PAR SONY.