I have one of these that started acting up last night. Pwrs up, has high voltage, no raster with input connected. I replaced the suspect optocoupler and cleaned up a bit of cracked solder today. Pwrd it up with no signal, I got the OSD so I figured it was ok now. Put it back on the desk and connected it to the pc via the BNC inputs.....came up for long enough to see the XP splash screen then a relay clicked and no raster after that. It does still display the OSD when there is no input.
I don't have a service manual for it....haven't had it that long. Any ideas?