LG Electronics 42LC2R IC Remove/Replacement, Small-Signal Discrete Transistor Removal/Replacement

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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.

Removal

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.

Replacement

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.

At IC Connections

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.

At Other Connections

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.

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Contents LCD TV Contents General Guidance Safety PrecautionsRAY Radiation Do not use a line Isolation Transformer during this checkElectrostatically Sensitive ES Devices Servicing PrecautionsSmall-Signal Discrete Transistor Removal/Replacement IC Remove/ReplacementPower Output, Transistor Device Removal/Replacement Diode Removal/ReplacementGeneral TV Specification Test method SpecificationApplication range Requirement for TestSet Optical Feature General SpecificationModel Specification RGB input DTV Component Video Input Y, PB, PRRGB Input PC Hdmi input DTV Mechanical SpecificationHdmi Input PC PCB assembly adjustment items Adjustment InstructionSET assembly adjustment items LP62xAdjustment of Component Adjustment of RF/AV/S-VIDEOAdjustment of RGB C-G-M-R-BLUE-BLACKAuto white Balance AV Manual white Balance AVMHVIDEO1 MSPG925FAPSM ARCCSM SSMKEY Funtion SVC RemoconNo power TroubleshootingCheck follow No PowerSymptom Check follow No Raster LCDLCD TV Case of occur strange screen into specific modeCase of doesn’t display the OSD Symptom 1 LED is White Case of unusual situation from RF mode Case of doesnt work normally at specific input mode SymptomCase of becomes unusual display from Hdmi mode When set doesn’t display normally at RF , AV modeWhen set doesnt display nromally at Component, RGB mode VSC B/D Case of no soundBlock Diagram Exploded View 37LC2R Description Exploded View Parts LIST37LC2RExploded VIEW42LC2R Exploded View Parts LIST42LC2R Main Board Capacitor Replacement Parts List0CE476WK6DC Description / Specification Description / Specification Coil & Core & Inductor Description / Specification FET & Transistor Description / Specification Description / Specification Description / Specification Control Board PREAMP&LED Board Page Page Page Page Mar
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37LC2R, 42LC2R specifications

LG Electronics has long been a notable player in the consumer electronics market, particularly in the television segment. Among its standout models are the 42LC2R, 50PC1R, 37LC2R, and 42PC3R, each designed to provide excellent viewing experiences with various features and technologies.

Starting with the 42LC2R, this model is known for its impressive 42-inch screen size, offering Full HD 1080p resolution that ensures sharp, vibrant images. The incorporation of LG's Adaptive Contrast technology enhances picture clarity by adjusting the contrast levels based on the content being displayed. Additionally, the 42LC2R features a slim design that makes it an elegant addition to any living space, combined with a reliable viewing angle, providing a great experience from different positions in the room.

Moving on to the 50PC1R, this Plasma TV boasts a larger 50-inch display, ideal for immersive movie-watching and gaming sessions. The 50PC1R supports a 720p resolution, which, while not Full HD, still delivers rich colors and great depth thanks to its plasma technology. One of the key highlights of this model is its 600Hz Real Motion Display, which significantly reduces motion blur, perfect for fast-paced sports and action films. Furthermore, the model's built-in surround sound technology creates an enriched audio ambiance, complementing the visual excellence.

The 37LC2R model, a slightly smaller option at 37 inches, still packs a punch with its high-quality display. It retains the hallmark of LG's LCD technology, boasting clear and consistent picture quality. With the integration of LG’s proprietary technologies, like XD Engine, the 37LC2R efficiently upscales lower-resolution content to provide enhanced detail and clarity. Its energy-efficient features are also commendable, making it a more sustainable choice without compromising performance.

Lastly, the 42PC3R incorporates advanced plasma technology, offering both a 42-inch screen and Full HD resolution. It stands out with LG’s Infinite Contrast feature, enabling deeper blacks and brighter whites. This model also embraces LG's stylish design philosophy, ensuring it looks modern and attractive in any home environment. Furthermore, it includes multiple connectivity options, such as HDMI ports and USB inputs, which enhance versatility and ease of use, allowing users to connect a variety of external devices.

Overall, each model—42LC2R, 50PC1R, 37LC2R, and 42PC3R—showcases LG Electronics' commitment to delivering high-quality displays, innovative technologies, and functional designs. Whether for enjoying high-definition movies or gaming, these televisions promise to enhance the viewing experience while adapting to various consumer needs.
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