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1. Precautions
Follow these safety, ESD, and servicing precautions to prevent personal injury and equipment damage.

1-1. Safety Precautions
1. Be sure that all built-in protective devices are in place. Restore any missing protective shields. 2. Make sure there are no cabinet openings through which people- particularly children- might insert fingers or objects and contact dangerous voltages. 3. When re-installing chassis and assemblies, be sure to restore all protective devices, including control knobs and compartment covers. 4. Design Alteration Warning: Never alter or add to the mechanical or electrical design of this equipment, such as auxiliary connectors, etc. Such alterations and modifications will void the manufacturer's warranty. 5. Components, parts, and wiring that appear to have overheated or are otherwise damaged should be replaced with parts which meet the original specifications. Always determine the cause of damage or overheating, and correct any potential hazards. 6. Observe the original lead dress, especially near sharp edges, AC, and high voltage power supplies. Always inspect for pinched, out-ofplace, or frayed wiring. Do not change the spacing between components and the printed circuit board. 7. Product Safety Notice: Some electrical and mechanical parts have special safety-related characteristics which might not be obvious from visual inspection. These safety features and the protection they provide could be lost if a replacement component differs from the original. This holds true, even though the replacement may be rated for higher voltage, wattage, etc. Components critical for safety are indicated in the parts list with symbols . Use only replacement components that have the same ratings, especially for flame resistance and dielectric specifications. A replacement part that does not have the same safety characteristics as the original may create shock, fire, or other safety hazards.

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Precautions

1-2. ESD Precautions
Certain semiconductor devices can be easily damaged by static electricity. Such components are commonly called "Electrostatically Sensitive (ES) Devices", or ESDs. Examples of typical ESDs are: integrated circuits, some field effect transistors, and semiconductor "chip" components. The techniques outlined below should be followed to help reduce the incidence of component damage caused by static electricity. CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other safety precautions. 4. Use only an "anti-static" solder removal device. Some solder removal devices not classified as "anti-static" can generate electrical charges sufficient to damage ESDs. 5. Do not use Freon-propelled chemicals. When sprayed, these can generate electrical charges sufficient to damage ESDs. 6. Do not remove a replacement ESD from its protective packaging until immediately before installing it. Most replacement ESDs are packaged with all leads shorted together by conductive foam, aluminum foil, or a comparable conductive material. 7. Immediately before removing the protective shorting material from the leads of a replacement ESD, touch the protective material to the chassis or circuit assembly into which the device will be installed. 8. Maintain continuous electrical contact between the ESD and the assembly into which it will be installed, until completely plugged or soldered into the circuit. 9. Minimize bodily motions when handling unpackaged replacement ESDs. Normal motions, such as the brushing together of clothing fabric and lifting one's foot from a carpeted floor, can generate static electricity sufficient to damage an ESD.

1. Immediately before handling a semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by touching a known earth ground. Alternatively, employ a commercially available wrist strap device, which should be removed for your personal safety reasons prior to applying power to the unit under test. 2. After removing an electrical assembly equipped with ESDs, place the assembly on a conductive surface, such as aluminum or copper foil, or conductive foam, to prevent electrostatic charge buildup in the vicinity of the assembly. 3. Use only a grounded tip soldering iron to solder or desolder ESDs.

1-3. Lithium Battery Precautions
1. Exercise caution when replacing a Lithium battery. There could be a danger of explosion and subsequent operator injury and/or equipment damage if incorrectly installed. 2. Be sure to replace the battery with the same or equivalent type recommended by the manufacturer. 3. Lithium batteries contain toxic substances and should not be opened, crushed, or burned for disposal.

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