CAUTION : Before servicing the DVD covered by this service
Electrostatically Sensitive (ES) Devices
data and its supplements and ADDENDUMS, read and
Some semiconductor (solid state) devices can be
follow the
SAFETY PRECAUTIONS NOTE
: if unforeseen
damaged easily by static electricity. Such components
circumstances create conflict between the following
commonly are called Electrostatically Sensitive (ES) Devices.
servicing precautions and any of the safety precautions in
Examples of typical ES devices are integrated circuits and
this publications, always follow the safety Precautions.
some field effect transistors and semiconductor chip
Remember Safety First:
components. The following techniques should be used to
help reduce the incidence of component damage
caused by static electricity.
General Servicing Precautions
1. Immediately before handling any emiconductor
1. Always unplug the DVD DC power cord from the DC
component or semiconductor-equipped assembly, drain
power source before:
off any electrostatic charge on your body by touching a
(1) Removing or reinstalling any component, circuit board,
known earth ground. Alternatively, obtain and wear a
module, or any other assembly.
commercially available discharging wrist strap device,
(2) Disconnection or reconnecting any internal electrical
which should be removed for potential shock reasons
plug or other electrical connection.
prior to applying power to the unit under test.
Caution :
A wrong part substitution or incorrect polarity
installation of electrolytic capacitors may result in an
2. After removing an electrical assembly equipped with ES
explosion hazard.
devices, place the assembly on a conductive surface
such as aluminum toil, to prevent electrostatic charge
2. Do not spray chemicals on or near this DVD or any of its
buildup or exposure of the assembly.
assemblies.
3. Use only a GROUNDED-tip soldering iron to solder or
3. Unless specified otherwise in this service data, clean
unsolder ES devices.
electrical contacts by applying an appropriate contact
cleaning solution to the contacts with a pipe cleaner,
4. Use only an anti-static solder removal device. Some
cotton-tipped swab, or comparable soft applicator.
solder removal devices not classified a "anti-static" can
Unless specified otherwise in this service data, lubrication
generate electrical charges sufficient to damage ES
of contacts is not required.
devices.
4. Do not defeat any plug/socket B+ voltage interlocks with
5. Do not use freon-propelled chemicals. These can
which instruments covered by this service manual might
generate electrical charge sufficient to damage ES
be equipped.
devices.
5. Do not apply AC power to this DVD and/or any of its
6. Do not remove a replacement ES device from its
electrical assemblies unless all solid-state device heat
protective package until immediately before you are
sinks are correctly installed
ready to install it. (Most replacement ES devices are
.
packaged with leads electrically shorted together by
6. Always connect test instrument ground lead to the
conductive foam, aluminum foil, or comparable
appropriate ground before connection the test
conductive material.)
instrument positive lead. Always remove the test
instrument ground lead last.
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
Insulation Checking Procedure
which the device will be installed.
Disconnect the attachment plug trom the AC outlet and
Caution : Be sure no power is applied to the chassis or
turn the power on. Connect an insulation resistance
circuit, and observe all other safety precautions.
meter(500V) to the blades of the attachment plug. The
insulation resistance between each blade of the
8. Minimize bodily motions when handling unpackaged
attachment plug and accessible conductive parts (Note 1)
replacement ES devices. (Normally harmless motion
should be more than 1M ohm.
such as the brushing together of your clothes fabric or
the lifting of your foot from a carpeted floor can
Note 1 :
Accessible Conductive Parts including Metal
generate static electricity sufficient to damage an ES
panels, input terminals, Earphone jacks, etc.
device.)
SERVICING PRECAUTIONS
3
All manuals and user guides at all-guides.com
