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7. Potentials, as high as 30.0 kV (For model with 20 inch CRT), 32.0 kV (For model with Round 27 inch CRT), 33.0 kV (For model with Flat 27 inch CRT) are present when this TV set is in operation. Operation of the TV set without the rear cover involvesthe danger of a shock hazard from the TV set power supply. Servicing should not be attempted by anyone who is not thoroughly familiar with the precautions necessary when working on high voltage equipment. Always discharge the anode of the picture tubeto the CRT ground of receiver before handling the tube. 8. After servicing make the following leakage current checks to prevent the customer from being exposed to shock hazards. 1.2. LEAKAGE CURRENT COLD CHECK 1. Unplug the AC cord and connect a jumper between the two prongs on the plug. 2. For physically operated power switches, turn power on. Otherwise skip step 2. 3. Measure the resistance value, with an ohmmeter, between the jumpered AC plug and each exposed metallic cabinet part on the receiver, such as screwheads, connectors, etc. When the exposed metallic part has a return path to the chassis, the readingshould be between 1 M and 12 M . When the exposed metal does not have a return path to the chassis, the reading must be infinity. 1.3. LEAKAGE CURRENT HOT CHECK 1. Plug the AC cord directly into the AC outlet. Do not use a isolation transformer for this check. 2. Connect a 1.5 k , 10 W resistor, in parallel with a 0.15 F capacitor, between each exposed metallic part on the set and a good earth ground, as shown in Figure 1. 3. Use an AC voltmeter, with 1 k potential across the resistor. /V or more sensitivity, to measure the
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