LG 21FA3AL/RL, Service Manual

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SAFETY PRECAUTIONS
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in
the Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to
prevent X-RADIATION, Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
General Guidance
A n
i s o
l
a
t
i o n
T r a n s f o r
m e r
s h o u l
d
a
l
w
a y s
b e
u s e d during the servicing of a
receiver whose chassis is not isolated from the AC power line.
Use a transformer of adequate power rating as this protects
the technician from accidents resulting in personal injury from
electrical shocks.
It will also protect the receiver and it's components from being
damaged by accidental shorts of the circuitry that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this TV receiver is blown,
replace it with the specified.
When replacing a high wattage resistor (Oxide Metal Film
Resistor, over 1W), keep the resistor 10mm away from PCB.
Keep wires away from high voltage or high temperature parts.
Due to high vacuum and large surface area of picture tube,
extreme care should be used in
h a n
d
l
i
n g t h e
P i
c t u r e
T u b e . Do not lift the
Picture tube by it's Neck.
X-RAY Radiation
Warning:
To determine the presence of high voltage, use an accurate
high impedance HV meter.
Adjust brightness, color, contrast controls to minimum.
Measure the high voltage.
The meter reading should indicate
23.5
¡
1.5KV: 14-19 inch, 26
¡
1.5KV: 19-21 inch,
29.0
¡
1.5KV: 25-29 inch, 30.0
¡
1.5KV: 32 inch
If the meter indication is out of tolerance, immediate service
and correction is required to prevent the possibility of
premature component failure.
The source of X-RAY RADIATION in this TV receiver is the
High Voltage Section and the Picture Tube.
For continued X-RAY RADIATION protection, the
replacement tube must be the same type tube as specified in
the Replacement Parts List.
1.5 Kohm/10W
To Instrument's
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
IMPORTANT SAFETY NOTICE
0.15uF