After the tv is on for about 1hr it gets a band of white dots moving a cross the mid of the screen whats the problem

I have a Mitsubishi TV and had the same problem. There is a mirror that moves to control each pixel. When some of them fail to move you get the white dots. Google your problem and a company will come up(sorry forgot the name).,you can buy the new part from them and they have exact utube videos to help you do the repair. Took me about an hour. Part was around $150. Very rewarding feeling when you turn the tv back on with no white dots.Still dot free after two years

Check the site linked below, and see the screen shots of defective LCD TVs, Surf it with patience. This should be a panel fault I assumes. http://electronicshelponline.blogspot.com/

projection tvs can display white dots from the dust that is on the reflector mirror your lamp shines the picture on before it is reflected onto the front screen of your tv, one must be very careful when cleaning this, may be worth a service man doing it for you

Hi,
White dots are due to bad DMD chip and qualified tv tech can replace required DMD chip in this tv to fix the picture issue.
Please contact nearest Samsung service center or local tv repair shop for repair estimate.
Thanks.

Here is a walk through on how to set your convergence.

A quick and easy way to try and let the TV realign the convergence try this...

1) Turn on the TV and tune to a channel and let it warm up for about a half an hour to let everything settle into its normal operating mode.

2) Press the Flash Focus button on the original TV remote. A cross pattern will show on the screen and the process is complete when the cross turns white and the TV returns to the program you were watching.

3) Do not press any other buttons until this process has completed.

If this does not adjust it enough you can adjust the convergence manually as follows:

1) Press the menu button on the original TV remote.

2) Use the arrow keys on the remote to highlight setup and press + button to select.

3) Use arrow keys to select convergence and press + button to select.

4) A pattern of white crosses appears, with a yellow [ ] around one of the
crosses. Aligned crosses (which do not need adjustment) look white and
have little or no red or blue showing. Crosses that are not aligned show
red or blue shades beyond their edges.

5) Use the arrow keys to move the [ ] to a cross that is not aligned. ***Note: start with crosses in the middle and work outward ****
*** TIP: Set the alignment while about 5 feet from TV for better results ****

6) Press the + button to select the cross and the [ ] will turn red indicating it is ready to adjust the Red convergence.

7) Use the arrow keys to move the red cross on top of the white one or at least as close as you can get it.

8) Once the Red is aligned press the + key again and the [ ] will turn blue. This indicates it is now ready to adjust the blue convergence.

9) Use the arrow keys to move the blue cross on top of the white one or at least as close as you can get it.

10) Once you have aligned the blue cross press the + button again and the [ ] should turn yellow.

11) Repeat steps 5 through 10 until all the crosses are aligned. To exit back to regular programming press the menu button on the remote.

Are these dots moving with image or stationary under a moving image. This is a key identifier

The white dots that come and go could be what is called ignition noise. Caused by something in your residence or on the power line to your living area. You will have to do some tracking. Take a portable radio and tune it to the 550mhz, you will hear a crackle or buzz, tune to the loudest that the buzz/crackle can be heard. Walk around to see were the noise gets to be the loudest. If it gets weaker you are moving away from the source. The source could be a dimmer switch for lighting, or a loose connection on a receptcle, or in the panel box that supplies the residence. Worst case it could be entering from outside source. I have tracked ignition noise as far as two houses away that had a bad butter control on a refrigerator that was on the same power line that supplied the neighbor hood. There are so many things this day and age that could be causing your dots. Yours come and go, so you will have to track it when it is acually seen on your tv. Sounds like something on a timer like refrigerator, Furnace, etc.

If you have the remote, go to the setup screen and move the picture. Converge has nothing to do with where the picture sits but, where the red, blue & green dots land. All you should see are pure white dots. There should be absolutely NO color ghost anywhere on the screen. If so, you need a bar / dot generator to set the convergence to center the dots.