Sony cdp cx 50 service manual

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Ñ 3 Ñ SAFETY CHECK-OUT After correcting the original service problem, perform the follow- ing 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). Leak- age 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 pas- sive VOM that is suitable. Nearly all battery operated digital multimeters that have a 2V AC range are suitable. (See Fig. A) Fig. A. Using an AC voltmeter to check AC leakage. To Exposed Metal Parts on Set 0.15 mF1.5k W AC voltmeter (0.75V) Earth Ground NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK OR BASE UNIT The laser diode in the optical pick-up block may suffer electrostatic breakdown because of the potential difference generated by the charged electrostatic load, etc. on clothing and the human body. During repair, pay attention to electrostatic breakdown and also use the procedure in the printed matter which is included in the repair parts. The flexible board is easily damaged and should be handled with care. NOTES ON LASER DIODE EMISSION CHECK The laser beam on this model is concentrated so as to be focused on the disc reflective surface by the objective lens in the optical pick- up block. Therefore, when checking the laser diode emission, ob- serve from more than 30 cm away from the objective lens. LASER DIODE AND FOCUS SEARCH OPERATION CHECK Carry out the ÒS curve checkÓ in ÒCD section adjustmentÓ and check that the S curve waveform is output repeatedly. SECTION 1 SERVICING NOTE 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 IDENTIFIƒS 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 PIéCES SONY DONT LES NUMƒROS SONT DONNƒS DANS CE MANUEL OU DANS LES SUPPLƒMENTS PUBLIƒS PAR SONY.