50PG79ED-AF (CHASSIS:PA84D) — LG TV Service Manual (repair manual)

Model
50PG79ED-AF (CHASSIS:PA84D)
Pages
41
Size
33.53 MB
Type
PDF
Document
Service Manual
Brand
Device
TV / Plasma
File
50pg79ed-af-chassis-pa84d.pdf
Date

View LG 50PG79ED-AF (CHASSIS:PA84D) Service Manual online

PLASMA TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : PA84D
MODEL : 50PG79ED      
50PG79ED-AF
CH
VOL
MENU
INPUT
ENTER
- 2 -
CONTENTS
CONTENTS ....................................................................................................... 2
SAFETY PRECAUTIONS....................................................................................3
SPECIFICATION..................................................................................................4
ADJUSTMENT INSTRUCTION ...........................................................................7
TROUBLE SHOOTING......................................................................................13
BLOCK DIAGRAM ............................................................................................22
EXPLODED VIEW  ........................................................................................... 25
SVC. SHEET .....................................................................................................27
PRINTED CIRCUIT DIAGRAM..........................................................................39
- 3 -
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 EXPLODED VIEW. 
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.
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.
If any fuse (or Fusible Resistor) in this monitor 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.
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 1M
and 5.2M
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.
Leakage Current Hot Check circuit
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
- 4 -
SPECIFICATIONS
NOTE : Specifications and others are subject to change without notice for improvement.
V
Application Range
This spec is applied to the 
PLASMA TV used PA84D Chassis.
Specification
Each part is tested as below without special appointment.
1) Temperature : 25±5°C (77±9°F), CST : 40±5
2) Relative Humidity: 65±10%
3) Power Voltage: Standard Input voltage (100-240V~, 50/60Hz)
* Standard Voltage of each product is marked by models.
4) Specification and performance of each parts are followed each drawing and specification by part number in accordance with SBOM.
5) The receiver must be operated for about 20 minutes prior to the adjustment.
V
Test Method
1) Performance : LGE TV test method followed.
2) Demanded other specification 
Safety : CB specification
EMC
: CISPR 13 specification
Chassis
PA84D
60PG30UD-AA
42/50PG60UD-AA
42/50PG20D-AA
50/60PG30FD-AA
50/60PG70FD-AB
Australia
LG
Model Name
Market
Brand
Remark
60PG30UD-AA
42/50PG60UD-AA
42/50PG20D-AA
50/60PG30FD-AA
50/60PG70FD-AB
Safety : IEC/EN60065
EMI
: CISPR 13 Class B
Australia
Model
Appliance
Market
Remark
Page of 41

Download LG 50PG79ED-AF (CHASSIS:PA84D) Service Manual (Repair Manual)

Here you can view online or download LG 50PG79ED-AF (CHASSIS:PA84D) Service Manual in pdf. This Service Manual can help you recover, restore, fix, disassemble and repair LG 50PG79ED-AF (CHASSIS:PA84D) Plasma. Information contained in LG 50PG79ED-AF (CHASSIS:PA84D) service manual (repair manual) typically includes:

  • Disassembly, troubleshooting, programming, maintenance, remote, adjustment, installation and setup instructions.
  • Schematics, wiring and block diagrams.
  • Printed wiring boards (PWB) and printed circuit boards (PCB).
  • Parts list (bill of materials).