Strange video behavior

Hi, while i was using my PAL Apple IIe, i got black screen.

Rebooting the computer with the ADT client disk, it boot showing a strange video (you can see a pic) and giving the commands it seems to be working.

Any idea to fix this video issue?


thanks a lot


I studied the electronic diagram and finally i pointed my finger on the 74166n. I replaced it and now it works fine.