SAFETY PRECAUTIONS
IMPORTANT SAFETY NOTICE
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 GuidanceLeakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
An isolation Transformer should always be used duringDo not use a line Isolation Transformer during this check.
the servicing of a receiver whose chassis is not isolated fromConnect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
the AC power line. Use a transformer of adequate power ratingbetween a known good earth ground (Water Pipe, Conduit, etc.)
as this protects the technician from accidents resulting inand the exposed metallic parts.
personal injury from electrical shocks.Measure the AC voltage across the resistor using AC
voltmeter with 1000 ohms/volt or more sensitivity.
It will also protect the receiver and it's components from beingReverse plug the AC cord into the AC outlet and repeat AC
damaged by accidental shorts of the circuitry that may bevoltage measurements for each exposed metallic part. Any
inadvertently introduced during the service operation.voltage measured must not exceed 0.75 volt RMS which is
corresponds to 0.5mA.
If any fuse (or Fusible Resistor) in this monitor is blown, replaceIn case any measurement is out of the limits specified, there is
it with the specified.possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
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.Leakage Current Hot Check circuit
AC Volt-meter
Due to high vacuum and large surface area of picture tube,
extreme care should be used in handling the Picture Tube.
Do not lift the Picture tube by it's Neck.
Good Earth Ground
such as WATER PIPE,
Leakage Current Cold Check(Antenna Cold Check)CONDUIT etc.
To Instrument's
With the instrument AC plug removed from AC source,exposed 0.15uF
connect an electrical jumper across the two AC plug prongs.METALLIC PARTS
Place the AC switch in the on position, connect one lead of
ohm-meter to the AC plug prongs tied together and touch other
ohm-meter lead in turn to each exposed metallic parts such as1.5 Kohm/10W
antenna terminals, phone jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1M1 and 5.2M1.
When the exposed metal has no return path to the chassis the
reading must be infinite.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.
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ACEC
LG-GOLDSTAR
