LG 50PG20-UA (CHASSIS:PU84A) Service Manual ▷ View online
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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.
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 lsolation 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.
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 circuitary that may be
inadvertently introduced during the service operation.
damaged by accidental shorts of the circuitary that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this monitor is blown, replace
it with the same specified type.
it with the same specified type.
When replacing a high wattage resistor (Oxide Metal Film
Resistor, over 1W), keep the resistor 10mm away from PCB.
Resistor, over 1W), keep the resistor 10mm away from PCB.
Keep wires away from high voltage or high temperature parts.
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 positioin, 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.
connect an electrical jumper across the two AC plug prongs.
Place the AC switch in the on positioin, 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 esposed 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 sepcified, 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 esposed 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 sepcified, 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
CANADA: LG Electronics Canada, Inc. 550 Matheson
Boulevard East Mississauga, Ontario L4Z 4G3
USA : LG Customer Interactive Center
P.O.Box 240007, 201 James Record Road Huntsville,
AL 35824
Digital TV Hotline 1-800-243-0000
AL 35824
Digital TV Hotline 1-800-243-0000
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
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SPECIFICATIONS.................................................................4
ADJUSTMENT INSTRUCTIONS ..........................................5
TROUBLE SHOOTING GUIDE ...........................................11
BLOCK DIAGRAM...............................................................41
EXPLODED VIEW...............................................................44
EXPLODED VIEW PARTS LIST .........................................45
SCHEMATIC DIAGRAM..........................................................
PRINTED CIRCUIT BOARDS .................................................
TABLE OF CONTENTS
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The specifications shown above may be changed without prior notice for quality improvement.
MODELS
AC100-240V ~ 50/60Hz
NTSC-M, ATSC, 64 & 256 QAM
VHF 2-13, UHF 14-69, CATV 1-135, DTV 2-69, CADTV 1-135
75 ohm
32 ~ 104°F (0 ~ 40°C)
Less than 80%
-4 ~ 140°F (-20 ~ 60°C)
Less than 85%
Dimensions
(Width x Height x Depth)
(Width x Height x Depth)
Weight
Power requirement
Television System
Program Coverage
External Antenna
Impedance
Television System
Program Coverage
External Antenna
Impedance
Environment condition
With stand
Without stand
With stand
Without stand
Without stand
Operating
Temperature
Operating Humidity
Temperature
Operating Humidity
Storage Temperature
Storage Humidity
Storage Humidity
42PG20 (42PG20-UA)
42PG20C (42PG20C-UA)
50PG20 (50PG20-UA)
50PG20C (50PG20C-UA)
MODELS
50PG30
(50PG30F-UA)
60PG30
(60PG30F-UA)
41.3 x 30.2 x 12.2 inches
1048.0 x 766.0 x 310.0 mm
41.3 x 28.1 x 3.3 inches
1048.0 x 713.0 x 83.5 mm
61.7 pounds / 28.0 kg
54.2 pounds / 24.6 kg
54.2 pounds / 24.6 kg
48.9 x 34.9 x 14.6 inches
1242.0 x 887.6 x 370.0 mm
48.9 x 32.6 x 3.5 inches
1242.0 x 827.2 x 88.0 mm
86.6 pounds / 39.3 kg
76.3 pounds / 34.6 kg
76.3 pounds / 34.6 kg
Dimensions
(Width x Height x Depth)
(Width x Height x Depth)
Weight
With stand
Without stand
With stand
Without stand
Without stand
48.9 x 34.9 x 14.6 inches
1242.0 x 887.6 x 370.0 mm
48.9 x 32.6 x 3.5 inches
1242.0 x 827.2 x 88.0 mm
86.6 pounds / 39.3 kg
76.3 pounds / 34.6 kg
76.3 pounds / 34.6 kg
57.3 x 38.8 x 16.3 inches
1455.0 x 985.0 x 414.0 mm
57.3 x 38.5 x 15.8 inches
1455.0 x 914.8 x 82.8 mm
137.6 pounds / 62.4 kg
127.8 pounds / 58.0 kg
127.8 pounds / 58.0 kg
MODELS
50PG60
(50PG60F-UA)
60PG60
(60PG60F-UA)
Dimensions
(Width x Height x Depth)
(Width x Height x Depth)
Weight
With stand
Without stand
With stand
Without stand
Without stand
48.9 x 34.9 x 14.6 inches
1242.0 x 887.6 x 370.0 mm
48.9 x 32.6 x 3.5 inches
1242.0 x 827.2 x 88.0 mm
86.6 pounds / 39.3 kg
76.3 pounds / 34.6 kg
76.3 pounds / 34.6 kg
57.3 x 38.8 x 16.3 inches
1455.0 x 985.0 x 414.0 mm
57.3 x 38.5 x 15.8 inches
1455.0 x 914.8 x 82.8 mm
137.6 pounds / 62.4 kg
127.8 pounds / 58.0 kg
127.8 pounds / 58.0 kg
SPECIFICATIONS
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ADJUSTMENT INSTRUCTIONS
1. Application Range
This spec. sheet is applied to all of the PU84A chassis.
2. Specification
(1) Because this is not a hot chassis, it is not necessary to use
an isolation transformer. However, the use of isolation
transformer will help protect test instrument.
transformer will help protect test instrument.
(2) Adjustment must be done in the correct order.
(3) The adjustment must be performed in the circumstance of
(3) The adjustment must be performed in the circumstance of
25±5
c
C of temperature and 65±10% of relative humidity if
there is no specific designation.
(4) The input voltage of the receiver must keep 100~240V,
50/60Hz.
Caution : 42PG20-UA must keep 100 ~ 120V, 50/60Hz.
Caution : 42PG20-UA must keep 100 ~ 120V, 50/60Hz.
(5) The receiver must be operated for about 15 minutes prior
to the adjustment.
O
After RGB Full White in HEAT-RUN Mode, the receiver must
be operated prior to the adjustment.
O
Enter into HEAT-RUN MODE
(1) Press the POWER ON KEY on R/C for adjustment.
(2) Press the ADJ KEY on R/C and enter EZ ADJUST
(2) Press the ADJ KEY on R/C and enter EZ ADJUST
Select “4. White Pattern” by using
D
/
E
(CH +/-) and press
ENTER(
V
)
Select “White” by using
F
/
G
(VOL +/-) and press
ENTER(
V
)
- Set is activated HEAT run without signal generator in this
mode.
- Single color pattern ( RED / BLUE / GREEN ) of HEAT RUN
MODE uses to check panel.
Caution: If you turn on a still screen more than 20 minutes
(Especially digital pattern, cross hatch pattern), an after
image may be occur in the black level part of the
screen.
image may be occur in the black level part of the
screen.
3. Download
(1) Execute ISP program “Mstar ISP Utility” and then click
“Config” tab.
(2) Set as below, and then click “Auto Detect” and check “OK”
message If display “Error”, Check connect computer, jig,
and set.
and set.
(3) Click “Connect” tab. If display “Can’t” , Check connect
computer, jig, and set.
(4) Click “Read” tab, and then load download file(XXXX.bin)
by clicking “Read”
(5) Click “Auto” tab and set as below
(6) Click “Run”.
(7) After downloading, check “OK” message.
(6) Click “Run”.
(7) After downloading, check “OK” message.