I have the same scope, same problem. No trace, I think it may be something in the high voltage transformer, flyback transformer? No experience in working on a tube like this is there any precautions I need to make?
Moderator edit: New thread created from old:
https://forum.allaboutcircuits.com/threads/scope-with-trace-problem.98147/
Moderator edit: New thread created from old:
https://forum.allaboutcircuits.com/threads/scope-with-trace-problem.98147/