Working on a 1902A for a C128 system for the collection and just finished recapping the monitor and the previous issue didn't go away where there is a single red, green, and blue line at the top of thr monitor. Has anyone seen something similar to this before and what part of the system i should focus on?
The monitor functions fine otherwise when connected to the computer and the color lines move when adjusting the vertical position.

Thanks for any suggestions.