Any CRT has at max 410 lines of resolution.Elizabeth, that's for standard definition CRTs. My Sony KD-30XS955 CRT-based high definition TV falls into the category that is referred to in this Wikipedia writeup as "Super Fine Pitch," which has a theoretical vertical resolution of 1080 lines.
I don't know precisely what it's actual measurable resolution would be, but I suspect it is likely to be upwards of 900 lines.
Best regards,
-- Al