AVR 100 (serv.man9) - Harman Kardon Audio Service Manual (repair manual). Page 3

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 static electricity.

1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any
electrostatic charge on your body by touching a known earth ground. Alternatively obtain and wear a commercially
available discharging wrist strap device, 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 “anti-static” can
generate electrical charges sufficient to damage ES devices,

5. Do not use freon-propelled chemicals. These can generate electrical change 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 unpacked replacement ES devices. (Otherwise harmless motion such as
the brushing together or your clothes fabric or the lifting of your foot from a carpeted floor can generate static
electricity sufficient to damage an ES device.)

Each precaution in this manual should be followed during servicing.
Components identified with the IEC symbol

 the parts list are of special significance to safety. When

replacing a component identified with          , use only the replacement parts designated, or parts  with the
same ratings or resistance, wattage or voltage that are designated in the parts list in this manual.
Leakage-current or resistance measurements must be made to determine that exposed parts are acceptably
insulated from the supply circuit before returning the product to the customer.