Testing a CTC-11 horizontal hold control

[Electronic M]

I'd suspect leakage in C72 ,73 and C75 dragging the grid positive.

I've been known to manually bias (with an external PS) grids to see if that is the cause and not the symptom...

One thing my Silvertone CTC-15 clone taught me is just because something in the H system worked before things went wrong, don't mean that it did not choose to die in sync with the initial problem...That set had raster and a hint of video (but bad lytics) to start, and after a recap it was dead...Change in the H osc paper cap put it far enough out of freq. range that it shorted the damper tube (which is surprisingly vulnerable to that in that set) and boost diode.