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I have run my 12" electromagnetic RR359 from 240 through 819 lines with no changes to the circuitry, just adjusting the coarse horizontal control.
Darryl
Thought comes to mind if that set could handle 1080i or 720p. B&W HDTV, use the luma jack. Though 720p would be nearly the same as 1440i, which seems too much a stretch beyond 819i.