Question about Projection Televisions

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LG projecter TV

The screen is showing a green or yellow circle in the middle lower section of the screen the rest of the picture is perfect a repair man told me that it was the LCD drive engine but after reading differant forams I just dont know anymore can any of you please help

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  • fbmullet Mar 04, 2008

    The TV is a LG RT44SZ80LB

  • fbmullet Mar 04, 2008

    Thank you for your fast reply I'm pretty sure the voltage is correct and the repair man all he did was tun the TV on look at the screen say that it was the drive engine and had me a bill but after reading some other comments online they talk a lot about the polarizing filter has this got any merit.

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Hello!

That color cause by a not correct voltage drops, this may cause by parts that is not functioning properly, Please try to regulate the power supply of your tv. But maybe the repairman is correct in his speculation.

melnavz

Posted on Mar 04, 2008

  • Emelio Navaja
    Emelio Navaja Mar 04, 2008

    He tell that the drive engine, Did he recommend for replacement the drive engine? Drive engine maybe its a general term that all assembly of the TV to project pictures on screen. This is a short expalanation of polarizing filter:



    Light travels from the back of the TV toward the front from a large bright light.


    1. A horizontal polarizing filter in front of the light blocks out all light waves except those vibrating horizontally.
    2. Only light waves vibrating horizontally can get through.
    3. The liquid crystal for this pixel is switched off, so light travels straight through it unchanged.
    4. Light waves emerge from the liquid crystal still vibrating horizontally.
    5. A vertical polarizing filter in front of the liquid crystal blocks out all light waves except those vibrating vertically. The horizontally vibrating light that travelled through the liquid crystal cannot get through the vertical filter.
    6. No light reaches the screen at this point. In other words, this pixel is dark.


    1. The bright light at the back of the screen shines as before.
    2. The horizontal polarizing filter in front of the light blocks out all light waves except those vibrating horizontally.
    3. Only light waves vibrating horizontally can get through.
    4. A transistor switches on the liquid crystal for this pixel. The crystal rotates light waves by 90° as they travel through it.
    5. Light waves that entered the liquid crystal vibrating horizontally emerge from it vibrating vertically.
    6. The vertical polarizing filter in front of the liquid crystal blocks out all light waves except those vibrating vertically. The vertically vibrating light that emerged from the liquid crystal can now get through the vertical filter.
    7. The pixel is lit up. A red, blue, or green filter gives the pixel its color.

    In that case, you TV got small error but it is negligible,

    However maybe be resolved by certified LG Technician, or at LG service center. But do not worry about that, that is tolerable.



    melnavz

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