RCA CRT TV thin white horizontal lines

Question

I suspect this is a standard malady for CRTs but here are the specifics of the set:

RCA 31" Home Theatre F31700GG chassis #CTC169JS5.

The thin white horizontal lines (slightly sloped) are across the entire picture and are spaced about 1 inch apart with some compression of spacing towards the top of the screen and expansion of spacing as towards the bottom of the screen (I suspect vertical scan related). The desired image is barely visible with a pinkish-grey cast. When I adjust the Screen potentiometer the TV shuts down.

I can replicate the lines on two other sets, a similar year model GE 27" and a really old RCA 19", by adjusting the Screen potentiometers.

I have all the schematics for the 31", a 275 MHz oscilloscope with built-in time interval multimeter, and two analog VOMs. Unfortunately I don't have a high voltage probe, power supply, or frequency generator.

Thank you,
Floydage