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You mentioned new tubes, it is likely 60Hz AC from the heater of a tube leaking to a cathode and into the deflection system. The vertical deflection frequency of the post 54' color system we feed our sets is 59.94Hz and thus when 60Hz power line frequency gets into the circuits associated with the picture it results in a horizontal bar of image disturbance that rolls vertically with respect to the image. The nature of the disturbance depends on what tube is leaking and the circuitry of the set. I'd guess it is the horizontal deflection or possibly synch tube that is the problem, but if you did not change those or putting the originals back does not fix the problem then try putting all of the originals back in one by one and power it up between each to see if the problem goes away...As soon as it goes away you will know that the last tube you changed before that power up is defective.
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