Sony hcd ep 50 liv service manual

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3 HCD-EP50LIV Notes 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. Flexible Circuit Board Repairing - Keep the temperature of the soldering iron around 270 ˚C dur- ing repairing. - Do not touch the soldering iron on the same conductor of the circuit board (within 3 times). - Be careful not to apply force on the conductor when soldering or unsoldering. SAFETY CHECK-OUT After correcting the original service problem, perform the follow- ing 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 indica- tion is 0.75 V, so analog meters must have an accurate low- voltage scale. The Simpson 250 and Sanwa SH-63Trd are ex- amples of a passive VOM that is suitable. Nearly all battery operated digital multimeters that have a 2 V AC range are suit- able. (See Fig. A) Fig. A. Using an AC voltmeter to check AC leakage. 1.5 k Ω 0.15 µF AC voltmete r (0.75 V) To Exposed Metal Parts on Set 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. The following caution label is located inside the unit. This appliance is classified as a CLASS 1 LASER product. The CLASS 1 LASER PRODUCT MARKING is located on the rear exterior.