Help with a 1982 RCA XL-100 GGR659SR?

[zeno]

Originally Posted by old_tv_nut

Does the sound buzz when this happens? (Can't hear any audio on your posted videos.)

Does this set have an AGC adjustment? I think I would try that first.

Ditto on AGC. there is a layout chart inside that will show it. Also on
your next post give the chassis number. Format is CTC-###-? its inside.
While the back is off turn the volume down & listen for any strange noises.
Has the look of a HV transformer breaking down.
Start there for now, got a few other ideas.

73 Zeno
LFOD !