Sony str de 185 rec service manual

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2 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. STR-DE185 AM tuner sectionTuning range Models of area code US With 10-kHz tuning scale: 530 -“ 1710 kHz 4) With 9-kHz tuning scale: 531 -“ 1710 kHz 4) Models of area code AEP, UK With 9-kHz tuning scale: 531 -“ 1602 kHz Antenna Loop antenna Intermediate frequency 450 kHz Usable sensitivity 50 dB/m (at 1,000 kHz or 999 kHz) S/N 45 dB (at 50 mV/m) Harmonic distortion 1.0 % (50 mV/m, 400 Hz) Selectivity At 9 kHz: 35 dB At 10 kHz: 40 dB 4) You can change the AM tuning scale to 9 kHz or 10 kHz. After tuning in any AM station, turn off the receiver. Hold down PRESET TUNING + and press ?/1. All preset stations will be erased when you change the tuning scale. To reset the scale to 10 kHz (or 9 kHz), repeat the procedure. GeneralPower requirementsArea code Power consumptionUS 120 V AC, 60 HzAEP, UK 230 V AC, 50/60 Hz Power consumption Area code Power consumptionUS 190 WAEP, UK 210 W Power consumption (during standby mode) 0.5 W (for models of all area code) AC outlets Area code AC outletsUS 1 switched, 120 W/1A MAXAEP, UK 1 switched, 100 W MAX Dimensions 430 × 145 × 300 mm (16 7/8 × 5 6/8 × 11 6/8 in.) including projecting parts and controls Mass (Approx.) 7.0 kg (15 lb 7 oz) Supplied accessories FM wire antenna (1) AM loop antenna (1) Remote commander RM-U185 (1) R6 (size-AA) batteries (2) Design and specifications are subject to change without notice. MODEL IDENTIFICATION - BACK PANEL - Part No. MODEL PART No. US 4-238-277-0s AEP 4-238-277-1s UK 4-238-277-2s

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3 TABLE OF CONTENTS 1. GENERAL Main unit ................................................................................. 4 Remote button description ....................................................... 5 2. DISASSEMBLY 2-1. Case ..................................................................................... 6 2-2. Front Panel Section ............................................................. 7 2-3. Back Panel ........................................................................... 7 2-4. Main Board ......................................................................... 8 3. TEST MODE ........................................................................ 9 4. DIAGRAMS 4-1. IC Pin Description ............................................................. 10 4-2. Circuit Boards Location .................................................... 11 4-3. Block Diagram -“ Main Section -“...................................... 12 4-4. Block Diagram -“ Power Section -“.................................... 13 4-5. Printed Wiring Board -“ Main Section -“............................ 14 4-6. Printed Wiring Boards -“ H/P, Outlet Section -“................. 15 4-7. Schematic Diagram -“ Main Section (1/2) -“...................... 16 4-8. Schematic Diagram -“ Main Section (2/2) -“...................... 17 4-9. Schematic Diagram -“ Display Section -“........................... 18 4-10. Printed Wiring Board -“ Display Section -“........................ 19 4-11. Printed Wiring Board -“ Power SW Section -“................... 20 5. EXPLODED VIEWS 5-1. Case Section ...................................................................... 21 5-2. Front Panel Section ........................................................... 22 5-3. Chassis Section ................................................................. 23 6. ELECTRICAL PARTS LIST ......................................... 24 STR-DE185 1.5 k -„¦ 0.15 µF AC voltmeter (0.75 V) To Exposed Metal Parts on Set Earth Ground Fig. A. Using an AC voltmeter to check AC leakage. 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 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)