siize of picture
on some stations the picture is missing at top and bottom
This may be due to the aspect ratio settings, and some channels - particularly older movies which have very(!) wide screen sizes - this will always be normal, since that's the way the film was mastered. So while in many cases this can be fixed, in some cases it will just "always be".
First, check to make sure your television's video settings for "Aspect Ratio" are set at "widescreen" or "16x9".
Then, check your cable/satellite box to make sure that the aspect ratio settings for the outgoing picture is also set at 16x9.
If it still occurs, that's going to be an issue inherent with the broadcasting (that's how the picture is transmitted - with the lines) and no settings in the television will change that.
If we can help further, please reach out here and we'll be happy to assist the best we can.
Thanks for your interest in Samsung products.
--Mr.Samsung