That's why I asked you. That is not contrast. The regulator below is scrin. It's more bright and the top one is focus. Focus.
The scrin must be well calibrated.
Set it 0 counterclockwise. And you increase the antenna cable very, very slowly. And go when I get to give image. If it gives. You did not comment on the tensions. Make it measure again. SCRIN to 314v put it.
The contrast is only regulated from the user menu.
Do you see the characters (OSD)?