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Samsung LCD tv display long black spots
First, turn off your television and unplug it from the power source for a few hours. Sometimes, turning off the power on your TV will force the stuck pixel to become unstuck when you finally plug your TV back to the mains.Use a clean, dry microfiber cloth, and gently wipe the TV screen in circular motions. Accumulated dirt can appear like black spots.Next, verify that the black spot issues aren’t caused by any devices plugged into your TV, like a console or cable box. Remove all cables connecting your TV to components, and then plug them back in. Sometimes, loose connections cause distorted images that look like dead pixels.
@Ujjal Samanta what you are describing sounds like a bad panel. We would need to know your TV’s exact model number as well as seeing what you see. Post some pictures of what your TV displays with your question. Use this guide for that Adding images to an existing question
