Really? Hmm, I'll have to look into that. Although I hope you mean 240p because 480p would kind of defeat the point sans a PVM-14L5/20L5, some (all?) BVM's, and maybe some JVC and/or Ikegami monitors. I'm not too familiar with those though. The 'HD' CRT's are pretty bad for retro from what I've read (no first hand experience).
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$601 on that sealed Snatcher with 4 hours to go!
Yes, I mean 240p. It's better to convert 480p into 240p than other resolutions. I'm still doing the research as well, but check the hardware forum at shmups, as they have a solution that has about 1.5 frames of lag that does work: https://shmups.system11.org/viewtopic.php?f=6&t=63226