Table Of Contents - Sony ICF-CD823 Service Manual

TABLE OF CONTENTS

1. GENERAL
········································································ 4
2. DISASSEMBLY
2-1. CABINET, LOWER ······················································ 5
2-2. MAIN BOARD ····························································· 6
2-3. PANEL (FRONT) SUB ASSY ······································ 6
2-4. OPTICAL PICK-UP BOLCK (KSM-213CDM) ·········· 7
2-5. TRANSFORMER BOARD ··········································· 7
3. TEST MODE ·······························································
4. ELECTRICAL ADJUSTMENTS ························
5. DIAGRAMS
5-1. BLOCK DIAGRAM ··················································· 11
5-2. CIRCUIT BOARDS LOCATION ······························· 13
5-3. SCHEMATIC DIAGRAM
- MAIN SECTION (1/2) - ·········································· 14
5-4. SCHEMATIC DIAGRAM
- MAIN SECTION (2/2) - ·········································· 17
5-5. PRINTED WIRING BOARD
- MAIN SECTION - ·················································· 20
5-6. PRINTED WIRING BOARD
- PANEL SECTION - ················································· 23
5-7. IC PIN FUNCTION DESCRIPTION ························· 25
5-8. IC BLOCK DIAGRAMS ············································ 26
6. EXPLODED VIEWS
6-1. LOWER CABINET SECTION ··································· 29
6-2. UPPER CABINET SECTION ···································· 30
6-3. OPTICAL PICK-UP SECTION
(KSM-213CDM) ························································· 31
7. ELECTRICAL PARTS LIST ·································
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK ! OR DOTTED
LINE WITH MARK ! 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 !
SUR LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE
DES PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ
DE FONCTIONNEMENT. NE REMPLACER CES COM-
POSANTS QUE PAR DES PIÈCES SONY DONT LES
NUMÉROS SONT DONNÉS DANS CE MANUEL OU DANS
LES SUPPLÉMENTS PUBLIÉS PAR SONY.
SAFETY CHECK-OUT
After correcting the original service problem, perform the following
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 microampers.).
Leakage current can be measured by any one of three methods.
8
1. A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. Follow the manufacturers' instructions to use these
10
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)
0.15 µ F
32
Fig. A. Using an AC voltmeter to check AC leakage.
Note on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
- 2 -
To Exposed Metal
Parts on Set
1.5 k Ω
Earth Ground
AC
voltmeter
(0.75 V)