Panasonic PV-4601 A, Service Manual

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DEVICES
Some semiconductor (solid state) devices can be damaged easily by static electricity.
Such components commonly are called Electrostatically Sensitive (ES) Devices.
Examples of typical ES devices are integrated circuits and some field-effect
transistors and semiconductor "chip" components. The following techniques should
be used to help reduce the incidence of component damage caused by electro static
discharge (ESD).
1. Immediately before handling any semiconductor component or
semiconductor-equipped assembly, drain off any ESD on your body by touching a
known earth ground. Alternatively, obtain and wear a commercially available
discharging ESD wrist strap, which should be removed for potential shock
reasons prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ES devices, place the
assembly on a conductive surface such as aluminum foil, to prevent electrostatic
charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static solder removal device. Some solder removal devices not
classified as "antistatic (ESD protected)" can generate electrical charge sufficient
to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges
sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package until
immediately before you are ready to install it. (Most replacement ES devices are
packaged with leads electrically shorted together by conductive foam, aluminum
foil or comparable conductive material).
7. Immediately before removing the protective material from the leads of a
replacement ES device, touch the protective material to the chassis or circuit
assembly into which the device will be installed.
CAUTION : Be sure no power is applied to the chassis or circuit, and observe all
other safety precautions.
8. Minimize bodily motions when handling unpackaged replacement ES devices.
(Otherwise harmless motion such as the brushing together of your clothes fabric
or the lifting of your foot from a carpeted floor can generate static electricity (ESD)
sufficient to damage an ES device).
"NOTE to CATV system installer:
This reminder is provided to call the CATV system installer's attention to Article
820-22 of the NEC that provides guidelines for proper grounding and, in particular,
specifies that the cable ground shall be connected to the grounding system of the
building, as close to the point of cable entry as practical."
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