So is this my jail bar problem?

[zeno]

First I must say I am proud of you. If it were the olden
days I would have got you a Master Tech licence as soon
as your required 2000 hrs on the permit was up.

Yes that sure looks like it. If you havent yet check everything
in the ABL from the tripler on. Also see what effect the ABL
control has on the lines. Also see if its at #115 at 9-90 module.
Should be a nice clean horz pulse there.
You can also disable the ABL by grounding the B of Q201 &
see if the lines go away.
If not its getting in somewhere else but this still is an
important clue.
Keep up the good work

73 Zeno