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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
An
isolation Transformer should always be used
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
handling the Picture Tube
.
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.
Before returning the receiver to the customer,
always perform an
AC leakage current check
on the exposed
metallic parts of the cabinet, such as antennas, terminals, etc.,
to be sure the set is safe to operate without damage of
electrical shock.
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source,
connect an electrical jumper across the two AC plug prongs.
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 as
antenna terminals, phone jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1MΩ and 5.2MΩ.
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.
Leakage Current Hot Check
(See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC
voltmeter with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC
voltage measurements for each exposed metallic part. Any
voltage measured must not exceed 0.75 volt RMS which is
corresponds to 0.5mA.
In case any measurement is out of the limits specified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
Leakage Current Hot Check circuit
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
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Summary of Contents for RT-39NZ40RB
Page 20: ... 20 TROUBLE SHOOTING All manuals and user guides at all guides com ...
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Page 27: ... 27 All manuals and user guides at all guides com ...
Page 28: ... 28 BLOCK DIAGRAM SIGNAL RT PRT PRT PRT All manuals and user guides at all guides com ...
Page 29: ... 29 BLOCK DIAGRAM SIGNAL RE RL PRT PRT PRT All manuals and user guides at all guides com ...
Page 31: ...MEMO 31 All manuals and user guides at all guides com a l l g u i d e s c o m ...
Page 32: ... 32 PRINTED CIRCUIT BOARD MAIN1 All manuals and user guides at all guides com ...
Page 34: ... 34 MAIN2 DEF All manuals and user guides at all guides com ...
Page 36: ... 36 SMPS All manuals and user guides at all guides com a l l g u i d e s c o m ...
Page 38: ... 38 PRT CONV OUT All manuals and user guides at all guides com ...
Page 39: ... 39 POWER S W SIDE AV CONTROL PRE AMP All manuals and user guides at all guides com ...
Page 40: ... 40 SVM INTERFACE CONTROL CONVERGENCE INTERFACE All manuals and user guides at all guides com ...
Page 42: ... 42 MICOM TOP MICOM BOTTOM All manuals and user guides at all guides com ...
Page 43: ... 43 100HZ TOP 100HZ BOTTOM All manuals and user guides at all guides com ...
Page 44: ...AV TOP 44 AV BOTTOM All manuals and user guides at all guides com ...
Page 45: ... 45 AUTO CVG SENSOR TOP AUTO CVG SENSOR BOTTOM All manuals and user guides at all guides com ...
Page 46: ... 46 HARMONICS All manuals and user guides at all guides com a l l g u i d e s c o m ...
Page 47: ...MEMO 47 All manuals and user guides at all guides com ...
Page 87: ...P NO 3854VA0094D S1 1 2 2003 03 13 PRT All manuals and user guides at all guides com ...
Page 88: ...P NO 3854VA0094D S1 2 2 2003 03 13 All manuals and user guides at all guides com ...
Page 89: ...P NO 3854VA0094D S2 1 2 2003 03 13 All manuals and user guides at all guides com ...
Page 90: ...P NO 3854VA0094D S2 2 2 2003 03 13 All manuals and user guides at all guides com ...
Page 92: ...Mar 2003 Printed in Korea P NO 3828VD0133H All manuals and user guides at all guides com ...