Philips MX975D, Руководство по обслуживанию

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PICTURE TUBE REPLACEMENT
PARTS REPLACEMENT
FIRE AND SHOCK HAZARD
1. Be sure all components are positioned in such a way as to avoid the possibility of adjacent
component shorts. This is especially important on those chassis which are transported to and from the
service shop.
2. Never release a repaired unit unless all protective devices such as insulators, barriers, covers, strain
reliefs, and other hardware have been installed in accordance with the original design.
3. Soldering and wiring must be inspected to locate possible cold solder joints, solder splashes, sharp
solder points, frayed leads, pinched leads, or damaged insulation (including the ac cord). Be certain to
remove loose solder balls and all other loose foreign particles.
4. Check across-the-line components and other components for physical evidence of damage or
deterioration and replace if necessary. Follow original layout, lead length, and dress.
5. No lead or component should touch a receiving tube or a resistor rated at 1 watt or more. Lead
tension around protruding metal surfaces or edges must be avoided.
6. Critical components having special safety characteristics are identified with an 'S' by the Ref. No. in
the parts list and enclosed within a broken line* (where several critical components are grouped in one
area) along with the safety symbol
on the schematic diagrams and /or exploded views.
7. When servicing any unit, always use a separate isolation transformer for the chassis. Failure to use
a separate isolation transformer may expose you to possible shock hazard, and may cause damage to
servicing instruments.
8. Many electronic products use a polarized ac line cord (one wide pin on the plug). Defeating this
safety feature may create a potential hazard to the servicer and the user. Extension cords which do not
incorporate the polarizing feature should never be used.
9. After reassembly of the unit, always perform an
ac leakage test
or resistance test from the line cord to
all exposed metal parts of the cabinet. Also, check all metal control shafts (with knobs removed),
antenna terminals, handles, screws, etc., to be sure the unit may be safely operated without danger of
electrical shock.
* Broken line ____ _ ____ _ ____ _ ____
IMPLOSION
1. All picture tubes used in current model receivers are equipped with an integral implosion system.
Care should always be used, and safety glasses worn, whenever handling any picture tube. Avoid
scratching or otherwise damaging the picture tube during installation.
2. Use only replacement tubes specified by the manufacturer.