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- 5 -

IC Remove/Replacement
Some chassis circuit boards have slotted holes (oblong) through
which the IC leads are inserted and then bent flat against the
circuit foil. When holes are the slotted type, the following technique
should be used to remove and replace the IC. When working with
boards using the familiar round hole, use the standard technique
as outlined in paragraphs 5 and 6 above.

1.  Desolder and straighten each IC lead in one operation by gently

prying up on the lead with the soldering iron tip as the solder
melts.

2.  Draw away the melted solder with an anti-static suction-type

solder removal device (or with solder braid) before removing the
IC.

1.  Carefully insert the replacement IC in the circuit board.
2.  Carefully bend each IC lead against the circuit foil pad and

solder it.

3.  Clean the soldered areas with a small wire-bristle brush.

(It is not necessary to reapply acrylic coating to the areas).

"Small-Signal" Discrete Transistor
Removal/Replacement
1.  Remove the defective transistor by clipping its leads as close as

possible to the component body.

2.  Bend into a "U" shape the end of each of three leads remaining

on the circuit board.

3.  Bend into a "U" shape the replacement transistor leads.
4.  Connect the replacement transistor leads to the corresponding

leads extending from the circuit board and crimp the "U" with
long nose pliers to insure metal to metal contact then solder
each connection.

Power Output, Transistor Device
Removal/Replacement
1.  Heat and remove all solder from around the transistor leads.
2. Remove the heat sink mounting screw (if so equipped).
3.  Carefully remove the transistor from the heat sink of the circuit

board.

4.  Insert new transistor in the circuit board.
5. Solder each transistor lead, and clip off excess lead.
6.  Replace heat sink.

Diode Removal/Replacement
1.  Remove defective diode by clipping its leads as close as

possible to diode body.

2.  Bend the two remaining leads perpendicular y to the circuit

board.

3.  Observing diode polarity, wrap each lead of the new diode

around the corresponding lead on the circuit board.

4.  Securely crimp each connection and solder it.
5. Inspect (on the circuit board copper side) the solder joints of

the two "original" leads. If they are not shiny, reheat them and if
necessary, apply additional solder.

Fuse and Conventional Resistor
Removal/Replacement
1.  Clip each fuse or resistor lead at top of the circuit board hollow

stake.

2.  Securely crimp the leads of replacement component around

notch at stake top.

3.  Solder the connections.

CAUTION: Maintain original spacing between the replaced
component and adjacent components and the circuit board to
prevent excessive component temperatures.

Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printed circuit
board will weaken the adhesive that bonds the foil to the circuit
board causing the foil to separate from or "lift-off" the board. The
following guidelines and procedures should be followed whenever
this condition is encountered.

To repair a defective copper pattern at IC connections use the
following procedure to install a jumper wire on the copper pattern
side of the circuit board. (Use this technique only on IC
connections).

1.  Carefully remove the damaged copper pattern with a sharp

knife. (Remove only as much copper as absolutely necessary).

2.  carefully scratch away the solder resist and acrylic coating (if

used) from the end of the remaining copper pattern.

3.  Bend a small "U" in one end of a small gauge jumper wire and

carefully crimp it around the IC pin. Solder the IC connection.

4.  Route the jumper wire along the path of the out-away copper

pattern and let it overlap the previously scraped end of the good
copper pattern. Solder the overlapped area and clip off any
excess jumper wire.

Use the following technique to repair the defective copper pattern
at connections other than IC Pins. This technique involves the
installation of a jumper wire on the component side of the circuit
board.

1.  Remove the defective copper pattern with a sharp knife.

Remove at least 1/4 inch of copper, to ensure that a hazardous
condition will not exist if the jumper wire opens.

2.  Trace along the copper pattern from both sides of the pattern

break and locate the nearest component that is directly
connected to the affected copper pattern.

3.  Connect insulated 20-gauge jumper wire from the lead of the

nearest component on one side of the pattern break to the lead
of the nearest component on the other side.
Carefully crimp and solder the connections.
CAUTION: Be sure the insulated jumper wire is dressed so the
it does not touch components or sharp edges.

- 6 -

This spec sheet is applied to the 42"/37" LCD TV used LP7BA
chassis

Each part is tested as below without special appointment.

(1) Temperature : 25 ± 5°C(77 ± 9°F), CST : 40 ± 5°C
(2) Relative Humidity : 65% ± 10%
(3) Power Voltage : Standard input voltage (100-240V~,

50/60Hz)

*Standard Voltage of each products is marked by models

(4) Specification and performance of each parts are followed

each drawing and specification by part number in
accordance with BOM.

(5) The receiver must be operated for about 20 minutes prior

to the adjustment.

(1) Performance : LGE TV test method followed
(2) Demanded other specification

Safety

: CE, IEC Specification

EMC

: CE, IEC

NOTE : Specifications and others are subject to change without notice for improvement.

No

Item

Specification

Remark

1. 

Video input applicable system

PAL-D/K, B/G, I, NTSC-M, SECAM,  PAL 60

2. 

Receivable Broadcasting System

1) PAL / SECAM BG

2)  PAL / SECAM DK

3) PAL I/I I

4) NTSC

3. 

RF Input Channel

PAL

NTSC

VHF

E2 ~ E12

2~83

UHF

E21 ~ E69

CATV 

S1 ~ S20

1~71

HYPER S21~ 

S47

4. 

Input Voltage

AC 100 ~ 240 V/50Hz, 60Hz 

5. Market

Non-EU

6. 

Active Screen Size

1067.308 mm (diagonal)

42.02 inches

940.3 mm (diagonal)

37.02 inches

7. 

Tuning System

FVS 100 program

FS

8. 

Operating Environment

1) Temp  : 0 ~ 40 deg

2) Humidity : 10 ~ 90 %RH

9. 

Storage Environment

1) Temp  : -20 ~ 50 deg

2) Humidity : 10 ~ 90 %RH

10. Display

LCD 

Module

- 7 -

No

Item

Specification

Remark

1 .

Panel

42" TFT WXGA LCD

37" TFT WXGA LCD

2.

Frequency range

H : 31 ~ 61Khz

PC Input

V : 56 ~ 75Hz

3.

Control Function

1) Contrast/Brightness

2)  H-Position / V-Position

3) Tracking : Clock / Phase

4) Auto Configure

5) Reset

4. 

Component Jack(480i/576i/480p/576p/720p/1080i) Y/Pb/Pr : 2EA

5.

Power ON

LED

Power consumption 

Green

≤ 260W(42")

≤ 240W(37")

Stand by

Cool

≤ 1W

Warm

≤ 40W

6.

LCD Module

Outline 

42"

983 x 576 x 47.3

(H)mm x (V)mm x (D)mm

Dimension

37"

877.0 x 516.8 x 55.5

Pixel Pitch

42"

0.227 x 0.681 x RGB

mm

37"

0.200 x 0.600 x RGB

Pixel Format

1366 x 768 Pixels RGB strip arrangement

Coating

Hard coating(3H), Anti-glare treatment 

of the front polarizer, 

Back Light

42"

18CCFL

37"

16CCFL

No

Item

Min

Typ

Max

Unit

Maker

Remark

1.

Luminance

AV

- 100IRE Full white window 

Componet

350

450

LPL(0RT)37",42"

pattern

HDMI

- APC : Dynamic

PC

250

350

2.

Contrast ratio

CR

700

900

37"

- APC : Dynamic

800

1000

42"

HDMI 720p Full Black Pattern 

DCR

8000

10000

37"/42"

Measure the black luminance 

after 30 seconds.

3.

Medium

X axis

0.283

0.285

0.287

DQA : ±0.015

Y axis

0.291

0.293

0.295

DQA : ±0.015

4.

Cool

X axis

0.274

0.276

0.278

DQA : ±0.015

Y axis

0.281

0.283

0.285

DQA : ±0.015

Torino

5.

Warm

X axis

0.311

0.313

0.315

DQA : ±0.015

Y axis

0.327

0.329

0.331

DQA : ±0.015

- 8 -

No

Resolution

H-freq(kHz)

V-freq.(kHz)

Pixel clock(MHz)

Remarks

1.

720*480

15.73

59.94

13.500

SDTV, DVD 480I(525I)

2.

720*480

15.75

60.00

13.514

SDTV, DVD 480I(525I)

3.

720*576

15.625

50.00

13.500

SDTV, DVD 576I(625I)

4.

720*480

31.47

59.94

27.000

SDTV 480P

5.

720*480

31.50

60.00

27.027

SDTV 480P

6.

720*576

31.25

50.00

27.000

SDTV 576P

7.

1280*720

44.96

59.94

74.176

HDTV 720P

8.

1280*720

45.00

60.00

74.250

HDTV 720P

9.

1280*720

37.50

50.00

74.25

HDTV 720P 50Hz

10.

1920*1080

33.72

59.94

74.176

HDTV 1080I

11.

1920*1080

33.75

60.00

74.250

HDTV 1080I

12.

1920*1080

28.125

50.00

74.250

HDTV 1080I 50Hz, 

13.

1920*1080

67.5

60.00

148.5

HDTV 1080P

14.

1920*1080

56.25

50

148.5

HDTV 1080P 50Hz

No

Resolution

H-freq(kHz)

V-freq.(kHz)

Pixel clock(MHz)

Remarks

1

720*400

31.469

70.08

28.32

DOS

2.

640*480

31.469

59.94

25.17

VESA(VGA)

3

640*480

37.500

75.00

31.50

VESA(VGA)

4

800*600

37.879

60.31

40.00

VESA(SVGA)

5

800*600

46.875

75.00

49.50

VESA(SVGA)

6

1024*768

48.363

60.00

65.00

VESA(XGA)

7

1024*768

56.476

70.06

75.00

VESA(XGA)

8

1024*768

60.023

75.02

78.75

VESA(XGA)

9

1280*768

47.693

59.99

80.125

WXGA(42XGA,50",60")

10

1360*768

47.700

60.00

84.62

WXGA(42XGA,50",60")

11

1366*768

47.700

60.00

84.62

WXGA(42XGA,50",60")

No

Resolution

H-freq(kHz)

V-freq.(kHz)

Pixel clock(MHz)

Remarks

1

720*400

31.469

70.08

28.32

DOS

2

640*480

31.469

59.94

25.17

VESA(VGA)

3

640*480

37.500

75.00

31.50

VESA(VGA)

4

800*600

37.879

60.31

40.00

VESA(SVGA)

5

800*600

46.875

75.00

49.50

VESA(SVGA)

6

1024*768

48.363

60.00

65.00

VESA(XGA)

7

1024*768

56.476

70.06

75.00

VESA(XGA)

8

1024*768

60.023

75.02

78.75

VESA(XGA)

9

1280*768

47.693

59.99

80.125

WXGA(42XGA,50",60")

10

1360*768

47.700

60.00

84.62

WXGA(42XGA,50",60")

11

1366*768

47.700

60.00

84.62

WXGA(42XGA,50",60")