Read LG 50PB2DR-AC (CHASSIS:PB61C) Service Manual online
PLASMA TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : PB61C
MODEL : 50PB2DR
50PB2DR-AC
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CONTENTS
SAFETY PRECAUTIONS ....................................................................................3
DESCRIPTION OF CONTROLS ..........................................................................4
SPECIFICATIONS ................................................................................................9
ADJUSTMENT INSTRUCTIONS .......................................................................12
BLOCK DIAGRAM & TROUBLE SHOOTING GUIDE ......................................19
EXPLODED VIEW ........................................................................................44,46
EXPLODED VIEW PARTS LIST ...................................................................45,47
REPLACEMENT PARTS LIST...........................................................................48
SCHEMATIC DIAGRAM.........................................................................................
PRINTED CIRCUIT DIAGRAM ..............................................................................
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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.
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.
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.
damaged by accidental shorts of the circuitry that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this monitor is blown, replace it
with the specified.
with the specified.
When replacing a high wattage resistor (Oxide Metal Film Resistor,
over 1W), keep the resistor 10mm away from PCB.
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.
extreme care should be used in handling the Picture Tube.
Do not lift the Picture tube by it's Neck.
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 1M
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 1M
Ω 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.
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.
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
1.5 Kohm/10W
To Instrument's
exposed
METALLIC PARTS
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
IMPORTANT SAFETY NOTICE
0.15uF
OK
TV
D/A
INPUT
INPUT
BRIGHT
MODE
DVD
ARC
EXIT
VOL
SIZE
INDEX
TIME
REVEAL
I/II
ADJUST
APM
Q.VIEW
MUTE
PR
MARK
MENU
LIVE TV
TEXT
PIP
GUIDE
INFO
VCR
POWER
1
2
3
4
5
6
7
8
9
0
FAV
LIST
?
PIP PR-
PIP PR+
PIP INPUT
SWAP
PAGE
SLEEP
TIME
SHIFT
SHIFT
TIME
SHIFT
SHIFT
Selects digital or analogue mode.
External input modes rotate in regular sequence:
Digital, Analogue, AV1-2, Component 1-2, RGB-
DTV (or RGB-PC), HDMI1/DVI, HDMI2.
Digital, Analogue, AV1-2, Component 1-2, RGB-
DTV (or RGB-PC), HDMI1/DVI, HDMI2.
Switches the set between ON and STANDBY.
Selects your desired picture format.
Adjusts brightness on screen.
It returns to the default settings brightness by
changing mode source.
changing mode source.
Use for DVR record or trick play.
Controls the
Controls the
mode.
For further details, see the DVR section.
Control some video cassette recorders or DVD players
("RECORD" button is not available for DVD player).
("RECORD" button is not available for DVD player).
Accepts your selection or displays the current mode.
Adjusts menu settings.
Selects menu item.
Increase/decrease the sound level.
Returns to the previously viewed programme.
Switches the sound on or off.
Selects a programme.
Move from one full set of screen information to the next one.
Displays the programme list.
Displays the selected favourite programmes.
Selects the sound output or the audio mode.
Concurrently, compare with the Dynamic, Standard,
Mild, User1 and User2 on the screen.
Mild, User1 and User2 on the screen.
Sets the sleep timer.
Adjust the screen Resolution, position, clock, and phase.
D/A INPUT
(Digital TV /
Analogue TV)
INPUT
POWER
ARC
+/-
OK
THUMBSTICK
(Up/Down/Left
Right/OK)
VOLUME +/-
Q.VIEW
MUTE
PROGRAMME +/-
PAGE UP/DOWN
LIST
FAV (FAVOURITE)
I/II
APM
SLEEP
ADJUST
NUMBER button
VCR/DVD
control buttons
mode control
buttons
1
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DESCRIPTION OF CONTROLS