LC-42/46/52D85X
i
LC-42/46/52D85X
Service Manual
SAFETY PRECAUTION
IMPORTANT SERVICE SAFETY PRECAUTION
WARNING
1. For continued safety, no modification of any circuit should be
attempted.
2. Disconnect AC power before servicing.
BEFORE RETURNING THE RECEIVER (Fire &
Shock Hazard)
Before returning the receiver to the user, perform the following
safety checks:
3. Inspect all lead dress to make certain that leads are not pinched,
and check that hardware is not lodged between the chassis and
other metal parts in the receiver.
4. Inspect all protective devices such as non-metallic control knobs,
insulation materials, cabinet backs, adjustment and compartment
covers or shields, isolation resistor-capacitor networks, mechanical
insulators, etc.
5. To be sure that no shock hazard exists, check for leakage current
in the following manner.
• Plug the AC cord directly into a 110-240 volt AC outlet.
• Using two clip leads, connect a 1.5k ohm, 10 watt resistor paral-
leled by a 0.15
µ
F capacitor in series with all exposed metal cabinet
parts and a known earth ground, such as electrical conduit or elec-
trical ground connected to an earth ground.
• Use an AC voltmeter having with 5000 ohm per volt, or higher, sen-
sitivity or measure the AC voltage drop across the resistor.
• Connect the resistor connection to all exposed metal parts having a
return to the chassis (antenna, metal cabinet, screw heads, knobs
and control shafts, escutcheon, etc.) and measure the AC voltage
drop across the resistor.
All checks must be repeated with the AC cord plug connection
reversed. (If necessary, a nonpolarized adaptor plug must be used
only for the purpose of completing these checks.)
Any reading of 0.74 Vrms (this corresponds to 0.5 mA rms AC.) or
more is excessive and indicates a potential shock hazard which
must be corrected before returning the monitor to the owner.
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SAFETY NOTICE
Many electrical and mechanical parts in LCD colour television have
special safety-related characteristics.
These characteristics are often not evident from visual inspection, nor
can protection afforded by them be necessarily increased by using
replacement components rated for higher voltage, wattage, etc.
Replacement parts which have these special safety characteristics are
identified in this manual; electrical components having such features
are identified by "
" and shaded areas in the Replacement Parts List
and Schematic Diagrams.
For continued protection, replacement parts must be identical to those
used in the original circuit.
The use of a substitute replacement parts which do not have the same
safety characteristics as the factory recommended replacement parts
shown in this service manual, may create shock, fire or other hazards.
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Service work should be performed only by qualified service technicians who are thoroughly familiar with all safety checks and the
servicing guidelines which follow:
DVM
AC SCALE
1.5k ohm
10W
TO EXPOSED
METAL PARTS
CONNECT TO
KNOWN EARTH
GROUND
0.15
µF
TEST PROBE
