This makes no sense.

Is this a flatscreen?
What is the inches of the flatscreen?

If your model is a 32" I fail to see a problem, as televisions around 50" and higher should be able to gain a clear picture.

THe only thing I could assume, is the maker of the series decided to be lazy when it came to display panels. Display
panels ( flatscreens ) deliver video content in resolution
( 640x480 ) which means it will display the image as is.

A real televsion has many internal hardware devices that
can take any image and display it, big as the screen itself.
Then their are scale-lines systems, as well was median filters.

During the 1990's many of these problems were solved. The only problem was the amount of people who were just too cheap, when it came to television.

IN GENERAL FLAT-SCREENS ARE BEING FORCED ON THE PUBLIC, FOR PEOPLE WHO CAN'T LIVE WITHOUT TELEVISION.

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My best advice, would to go in store with a more portible system and test each display, to see if the results change.
Another idea, is the in betweens. The device you are using?

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Yes cables can and can not affect the way an image is projected. It depends. With an RF device nowadays, the image can be extra clean because of the lack of Radio waves interrupting the signal.

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You have to be more detailed in your problem. I have a regular television that has a great picture but at the same time, the image seems to be jumping, or vibrating.
So I switched to another television i found outside

Some people are throwing out their good 1990's monster sized hi-end televisions, not because it is big, but because they have the money to burn.

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