Sony hcd grx 2 service manual

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Ñ 3 Ñ 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, 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 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 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) 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. TABLE OF CONTENTS 1. GENERAL .......................................................................... 4 2. DISASSEMBLY 2-1. CD Door ............................................................................. 5 2-2. CD Mechanism Deck ......................................................... 5 2-3. Front Panel ......................................................................... 6 2-4. Main Board and H.P Board ................................................ 6 2-5. CD Tray .............................................................................. 7 2-6. CD Decoder Board ............................................................. 7 2-7. Base Unit ............................................................................ 8 2-8. Cassette Lid (L)/(R) ............................................................ 8 3. MECHANICAL ADJUSTMENTS ............................... 9 4. ELECTRICAL ADJUSTMENTS ................................. 9 5. DIAGRAMS 5-1. Circuit Boards Location ................................................... 14 5-2. Brock Diagrams ¥ Deck Section ................................................................... 15 ¥ Tuner/CD Section ............................................................ 17 5-3. IC Brock Diagrams ........................................................... 19 5-4. Schematic Diagram ÑMain Section Ñ ........................... 24 5-5. Printed Wiring Board Ñ Main Section Ñ ....................... 29 5-6. Printed Wiring Board ÑCD Section Ñ ........................... 34 5-7. Schematic Diagram ÑCD Section Ñ .............................. 39 5-8. Schematic Diagram Ñ Panel Section Ñ ......................... 43 5-9. Printed Wiring Board ÑPanel Section Ñ ........................ 47 5-10. IC Pin Function ................................................................ 52 6. EXPLODED VIEWS 6-1. Cabinet Section ................................................................. 54 6-2. Front Panel Section .......................................................... 55 6-3. Cassette Button Section .................................................... 56 6-4. Cassette Mechanism Deck Section ................................... 57 6-5. CD Mechanism Deck Section 1 ....................................... 58 6-6. CD Mechanism Deck Section 2 ....................................... 59 6-7. Base Unit Section (KSM-213BCM) ................................. 60 7. ELECTRICAL PARTS LIST ........................................ 61