Sony str de 425 rec service manual

Page 1

Ñ 2 Ñ 1. GENERALááááááááááááááááááááááááááááááááááááááááááááááááááá\ áááááááááááá 3 2. TEST MODEááááááááááááááááááááááááááááááááááááááááááááááááááá\ ááááááááá 4 3. DIAGRAMS 3-1. Circuit Boards Location ááááááááááááááááááááááááááááááááááááááááááááááááááá\ áá 5 3-2. Block Diagram ááááááááááááááááááááááááááááááááááááááááááááááááááá\ áááááááááááááááá 7 3-3. Schematic Diagram Ñ Display Section Ñ áááááááááááááááááááááááá 9 3-4. Printed Wiring Board Ñ Display Section Ñ ááááááááááááááááááá 11 3-5. Schematic Diagram Ñ Power Section Ñ áááááááááááááááááááááááá 13 3-6. Printed Wiring Board Ñ Power Section Ñ ááááááááááááááááááááá 15 3-7. Printed Wiring Board Ñ Main Section Ñ ááááááááááááááááááááááá 17 3-8. Schematic Diagram Ñ Main Section (1/3) Ñ ááááááááááááááááá 19 3-9. Schematic Diagram Ñ Main Section (2/3) Ñ ááááááááááááááááá 21 3-10. Schematic Diagram Ñ Main Section (3/3) Ñ ááááááááááááááááá 23 3-11. IC Pin Function Description ááááááááááááááááááááááááááááááááááááááááááááá 25 3-12. IC Block Diagrams ááááááááááááááááááááááááááááááááááááááááááááááááááá\ áááááááá 27 4. EXPLODED VIEWS 4-1. Front Panel Section ááááááááááááááááááááááááááááááááááááááááááááááááááá\ ááááááá 29 4-2. Chassis Section ááááááááááááááááááááááááááááááááááááááááááááááááááá\ áááááááááááááá 30 5. ELECTRICAL PARTS LISTáááááááááááááááááááááááááááááááá 31 TABLE OF CONTENTS 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 par t 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 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. 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 Ë LA SƒCURITƒ! LES COMPOSANTS IDENTIFƒS PAR UNE MARQUE ! 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. Dimensions 430 ´ 145 ´ 295 mm Mass(Approx.) STR-DE425: 7.9 kg Supplied FM wire aerial (1) accessories AM loop aerial (1) Remote controller (remote) (1) Size AA (R6) batteries (2) Design and specifications are subject to chang e without notice. Specifications indicated are measured at 230 VAC, 50 Hz

Page 2

Ñ 3 Ñ SECTION 1 GENERAL 1 235 6 7 8 9 !¼ !Á !ª !£ !¢ !¤ !° !» !¦ !¥ @¼ @Á @¥ @» @£ @¦ @¢ @¤ @° @ª #¼ #Á 4 1 2 3 4 5 7 8 6 9 !¼ !Á !ª !£ !¢ !° 1 POWER switch (I/u) 2 CENTER LEVEL +, Ð buttons 3 REAR LEVEL +, Ð buttons 4 PRO LOGIC, C.STUDIO, HALL indicators 5 5.1/DVD INPUT, BASS BOOST indicators 6 MASTER VOLUME control 7 BALANCE control 8 TREBLE control 9 BASS control !¼ MUTING button/indicator !Á SURROUND ON/OFF button !ª SURROUND EFFECT/DELAY, MODE buttons !£ SET UP, 5.1/DVD INPUT, BASS BOOST buttons !¢ TV/LD button !° TAPE/MD button !¤ PHONO button!¦ TUNER button !¥ CD button !» VIDEO button @¼ Numeric buttons @Á DIRECT TUNING, SHIFT buttons @ª CHARACTER, DISPLAY buttons @£ MEMORY button @¢ FM/AM button @° PRESET/CHARACTER +, Ð buttons @¤ FM MODE button @¦ SLEEP button @¥ TUNING/PTY SELECT +, Ð buttons @» RDS PTY, EON buttons #¼ PHONES jack #Á SPEAKERS A, B ON/OFF buttons 1 ANTENNA (FM/AM) 2 5.1/DVD INPUT 3 y SIGNAL GND 4 MONITOR 5 WOOFER 6 FRONT SPEAKERS (A/B) 7 AC OUTLET 8 AC power cord9 SURROUND SPEAKERS (CENTER) 0 SURROUND SPEAKERS (REAR) !Á VIDEO !ª TV/LD !£ TAPE/MD !¢ CD !° PHONO LOCATION AND FUNCTION OF CONTROLS [FRONT PANEL] [REAR PANEL]