Samsung D61B, Training Manual

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1-3 Servicing Precautions
1. Servicing precautions are printed on the
cabinet. Follow them.
2. Always unplug the unit’s AC power cord from
the AC power source before attempting to: (a)
Remove or reinstall any component or
assembly, (b) Disconnect an electrical plug or
connector, (c) Connect a test component in
parallel with an electrolytic capacitor.
3. Some components are raised above the printed
circuit board for safety. An insulation tube or
tape is sometimes used. The internal wiring is
sometimes clamped to prevent contact with
thermally hot components. Reinstall all such
elements to their original position.
4. After servicing, always check that the screws,
components and wiring have been correctly
reinstalled. Make sure that the portion around
the serviced part has not been damaged.
5. Check the insulation between the blades of the
AC plug and accessible conductive parts
(examples: metal panels, input terminals and
earphone jacks).
6. Never defeat any of the B+ voltage interlocks.
Do not apply AC power to the unit (or any of
its assemblies) unless all solid-state heat sinks
are correctly installed.
7. Always connect a test instrument’s ground
lead to the instrument chassis ground before
connecting the positive lead; always remove
the instrument’s ground lead last.
8. Plasma display panels have partial afterim-
ages when a same picture continues to be dis-
played for a certain time. This happens due to
the degradation of brightness caused by a
scale-down effect.
To prevent such afterimages when displaying
a same picture for a certain time, be sure to
reduce the level of brightness and contrast.
ex) Contrast : 50 or 75, Brightness : 25
9. Plasma display is an array of pixels(cells).
Therefore, if at least 99.9% pixels keep normal,
the appropriate panel is judged as ‘approved
product.’ Even though some of pixels keep
luminescent or always light off, do not worry
because the panel is approved.
Precautions
Samsung Electronics 1-3
Warning 1 : First read the “Safety Precautions” section of this manual. If some unforeseen circumstance creates a
conflict between the servicing and safety precautions, always follow the safety precautions.
Warning 2 : An electrolytic capacitor installed with the wrong polarity might explode.