Sony cfd zw 750 service manual

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Ð 3 Ð To Exposed Metal Parts on Set 0.15 mF 1.5k W AC voltmeter (0.75V) 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, ÒmetallizedÓ 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 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) CHUCK PLATE JIG ON REPAIRING On repairing CD section, playing a disc without the CD lid, use Chuck Plate Jig. ¥ Code number of Chuck Plate Jig: X-4918-255-1 LASER DIODE AND FOCUS SEARCH OPERATION CHECK 1. Turn on POWER button and press CD button to CD position. 2. Open the CD lid. 3. Turn on S801 as following figure. 4. Press the ( P (CD) button. 5. Confirm the laser diode emission while observing the objecting lens. When there is no emission, Auto Power Control circuit or Optical Pick-up is broken. Objective lens moves up and down three times for focus search. S801 SERVICING NOTES