Got this one to repair and return - normally don't do this but it's for a friend so I said I'd have a look at it.
The problem is the picture is fuzzy, each line is skipping a few pixels randomly, and sometimes it loses vertical sync. It also has difficulty with composite video inputs, they always show "No Signal". OSD is affected as well as the video.
I tore it down and checked the regulators. They're all 3.3V; one is outputting 3.29V, another 3.31V, but there's one on the board that's doing 3.25V. It's a little low, so I scoped the output (with my new DS1102E
) - sure enough, it's oscillating at around 400kHz with over 1Vp-p of ripple. 
Fault is either the regulator (massive D2PAK device - lots of fun to remove) - or one of the caps. I hope it's the caps as those will be far easier to replace.
The problem is the picture is fuzzy, each line is skipping a few pixels randomly, and sometimes it loses vertical sync. It also has difficulty with composite video inputs, they always show "No Signal". OSD is affected as well as the video.
I tore it down and checked the regulators. They're all 3.3V; one is outputting 3.29V, another 3.31V, but there's one on the board that's doing 3.25V. It's a little low, so I scoped the output (with my new DS1102E
) - sure enough, it's oscillating at around 400kHz with over 1Vp-p of ripple. Fault is either the regulator (massive D2PAK device - lots of fun to remove) - or one of the caps. I hope it's the caps as those will be far easier to replace.
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