Samsung MX-J730, Service Manual

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1. Precaution
1.2. 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 may be 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) Insulation Checking Procedure :
Disconnect the power cord from the AC source. Connect an insulation resistance meter (500 V) to the blades of the
AC plug. The insulation resistance between each blade of the AC plug and accessible conductive parts (see above)
should be greater than 1 megohm.
7) 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.
8) 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.
CAUTION
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.
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