On Tuesday, 13 August 2019 14:44:08 UTC+1, wrote:

This is an old-style CRT monitor from very roughly the mid-1980s. I would start with the electrolytic caps first. Mind all safety processes prior to working on it. While you are 'in there', clean everything and look for any corroded or loose connections, as the symptoms you describe could also be heat-related.

Best of luck!

Peter Wieck
Melrose Park, PA

Could also be due to arcing. Which may well be stoppable at this stage by washing the affected area and drying very thoroughly.


NT