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Precaution

1. Precaution
To avoid possible damages or electric shocks or exposure to radiation, follow the instructions below with regard to safety, installation, service and ESD.

1-1 Safety Precautions
1. Make sure all protective devices are properly installed including non-metallic handles and compartment covers when installing or re-installing the chassis or chassis assemblies. Make sure that no gaps exist between the cabinets for children to insert their fingers in to prevent children from receiving electric shocks. 6. Errors may occur when the resistance is below 1.0 or over 5.2 . In these cases, make sure that the device is repaired before sending it back to the customer. 3. Check for Electricity Leakage (Figure 1-1) Warning: Do not use an insulated transformer for checking the leakage. Use only those current leakage testers or mirroring systems that comply with ANSIC 101.1 and the Underwriter Laboratory's specifications (UL1410, 59.7). 5. Warning for Engineering Changes: Never make any changes or additions to the circuit design or the internal part for this product. Ex: Do not add any audio or video accessory connectors. This might cause physical damage. Furthermore, any changes or additions to the original design/engineering will invalidate the warranty. Warning - Hot Chassis: Some TV chassis are directly connected to one end of the AC power cord for electrical reasons. Without insulated transformers, the product can only be repaired safely when the chassis is connected to the earthed end of the AC power source. To make sure the AC power cord is properly connected, follow the instructions below. Use the voltmeter to measure the voltage between the chassis and the earthed ground. If the measurement is over 1.0V, unplug the AC power cord and change the polarity before reinserting it. Measure the voltage between the chassis and the ground again. 7. Some TV chassis are shipped with an additional secondary grounding system. The secondary system is adjacent to the AC power line. These two grounding systems are separated in the circuit using an unbreakable/unchangeable insulation material. When any parts, material or wiring appear overheated or damaged, replace them with new regular ones immediately. When any damage or overheating is detected, correct this immediately and make a regular check of possible errors.

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DEVICE UNDER TEST TEST ALL EXPOSED METAL SURFACES 2-WIRE CORD ALSO TEST WITH PLUG REVERSED (USING AC ADAPTER PLUG AS REQUIRED)

LEAKAGE CURRENT TESTER

(READING SHOULD NOT BE ABOVE 0.5mA)

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EARTH GROUND

Fig. 1-1 AC Leakage Test 4. A high voltage is maintained within the specified limits using safety parts, calibration and tolerances. When voltage exceeds the specified limits, check each special part.

9. Check for the original shape of the lead, especially that of the antenna wiring, any sharp edges, the AC power and the high voltage power. Carefully check if the wiring is too tight, incorrectly placed or loose. Never change the space between the part and the printed circuit board. Check the AC power cord for possible damages. Keep the part or the lead away from any heat-emitting materials.

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10. Safety Indication: Some electrical circuits or device related materials require special attention to their safety features, which cannot be viewed by the naked eye. If an original part is replaced with another irregular one, the safety or protective features will be lost even if the new one has a higher voltage or more watts. Critical safety parts should be bracketed with ( ! ). Use only regular parts for replacements (in particular, flame resistance and dielectric strength specifications). Irregular parts or materials may cause electric shock or fire. 11. Pay additional attention to the current leakage as the voltage between the power board and the ballast is 220 to 440v, i.e. very high. And also beware of possible electric shock from the primary power source.

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1-2 Servicing Precautions
Warning 1: First carefully read the "Safety Instruction" in this service manual. When there is a conflict between the service and the safety instructions, follow the safety instruction at all times. Warning 2: Any electrolytic capacitor with the wrong polarity will explode. 1. 2. The service instructions are printed on the cabinet, and should be followed by any service personnel. Make sure to unplug the AC power cord from the power source before starting any repairs. (a) Remove or re-install parts or assemblies. (b) Disconnect the electric plug or connector, if any. (c) Connect the test part in parallel with the electrolytic capacitor. Some parts are placed at a higher position than the printed board. Insulated tubes or tapes are used for this purpose. The internal wiring is clamped using buckles to avoid contact with heat emitting parts. These parts are installed back to their original position. After the repair, make sure to check if the screws, parts or cables are properly installed. Make sure no damage is caused to the repaired part and its surroundings. Check for insulation between the blade of the AC plug and that of any conductive materials (i.e. the metal panel, input terminal, earphone jack, etc). 6. Insulation Check Process: Unplug the power cord from the AC source and turn the switch on. Connect the insulating resistance meter (500v) to the AC plug blade. The insulating resistance between the blade of the AC plug and that of the conductive material should be more than 1 . 7. Any B+ interlock should not be damaged. If the metal heat sink is not properly installed, no connection to the AC power should be made. Make sure the grounding lead of the tester is connected to the chassis ground before connecting to the positive lead. The ground lead of the tester should be removed last. Beware of risks of any current leakage coming into contact with the high-capacity capacitor.

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10. The sharp edges of the metal material may cause physical damage, so ensure wearing protective gloves during the repair.

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1-3 Static Electricity Precautions
1. Some semi-conductive ("solid state") devices are vulnerable to static electricity. These devices are known as ESD. ESD includes the integrated circuit and the field effect transistor. To avoid any materials damage from electrostatic shock, follow the instructions described below. Remove any static electricity from your body by connecting the earth ground before handling any semi-conductive parts or ass'ys. Alternatively, wear a dischargeable wrist-belt. (Make sure to remove any static electricity before connecting the power source - this is a safety instruction for avoiding electric shock) Remove the ESD ass'y and place it on a conductive surface such as aluminum foil to prevent accumulating static electricity. Do not use any Freon-based chemicals. Such chemicals will generate static electricity that causes damage to the ESD. Use only grounded-tip irons for soldering purposes. 6. Use only anti-static solder removal devices. Most solder removal devices do not support an anti-static feature. A solder removal device without an anti-static feature can store enough static electricity to cause damage to the ESD. Do not remove the ESD from the protective box until the replacement is ready. Most ESD replacements are covered with lead, which will cause a short to the entire unit due to the conductive foam, aluminum foil or other conductive materials. Remove the protective material from the ESD replacement lead immediately after connecting it to the chassis or circuit ass'y. Take extreme caution in handling any uncovered ESD replacements. Actions such as brushing clothes or lifting your leg from the carpet floor can generate enough static electricity to damage the ESD.

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CAUTION
These servicing instructions are for use by qualified service personnel only. To reduce the risk of electric shock do not perform any servicing other than that contained in the operating instructions unless you are qualified to do so.

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1-4 Installation Precautions
1. For safety reasons, more than two people are required for carrying the product. 5. Make sure to turn the power off and unplug the power cord from the outlet before repositioning the product. Also check the antenna cable or the external connectors if they are fully unplugged. Damage to the cord may cause fire or electric shock. Keep the antenna far away from any high-voltage cables and install it firmly. Contact with the high-voltage cable or the antenna falling over may cause fire or electric shock. Check the basics of the screen test. - Image position/size, Tilt adjustment, Actuator activation

6. 2. Keep the power cord away from any heat emitting devices, as a melted covering may cause fire or electric shock. When installing the product, make sure to keep it away from the wall (more than 10cm/4 inches) for ventilation purposes. Poor ventilation may cause an increase in the internal temperature of the product, resulting in a shortened component life and degraded performance. Bend the external antenna cable when connecting it to the product. This is a measure to protect it from being exposed to moisture. Otherwise, it may cause a fire or electric shock.

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