Look to the 200V filter cap, a $2 gamble.
Symptoms are any one or more of the following:
Too bright.
Streaking.
Darker on left than right.
Jailbars. ( vert dark bars)
Poor all around pix.
Can look like soft CRT.
Also it may be the CRT is a little weak. Screen shots of real programing
helps there. There may be a cheat to get more life.
Someone may have a manual & can tell you the "C" number.
If not take chassis pixs (nudies) & it can be traced down easily.
This is a VERY common problem across all brands.
73 Zeno