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I will go thru the ground stakes again.
also noted that the vert hold only works at the extreme CCW, more that about 1/4 turn off ground results in rapid rolling to the point of locking in with two flickering pics and the blanker centered on the screen.
My guess is the resistor in series with the hold pot has increased and/or I have some leakage thru a feedback cap that maybe allowing some DC to get, either way something is upseting the bias and or time constant the vert is running at.
I will prob just replace ALL the film caps and resistors on the vert sweep. Its not that hard esp since its a PCB.
will also check the sync pulse vert signal, the sams shows pulling the multivibrator (bright down to avoid burning the CRT) and scoping the output from the integrator. the Sams show what looks like a vert pulse with 'some" horz hash in between but at a much lower PP.
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