Repurposing VGA CRT as composite monitor

[karoru]

Hey, I've got this old Datas CH-0423V VGA B/W computer display. It has nice, crisp picture and I'm wondering about repurposing it as composite monitor for my old gaming systems repair.

Any ideas if that's doable easily? Most googling gives me some Chinese composite to VGA upscalers, but I really don't
care about getting some fancy uber-cool resolutions and other nice features, I just want something to connect old
gaming system to check if it's working and if the picture makes any sense. I remember in the magic days of CRT
technicians made some hacks to add composite to old TVs (with or without any concerns about things such as galvanic
isolation, nothing beats making your VCR chassis hot by connecting it to a TV), but I wonder whether that's easily
doable on a semi-modern computer display (it has only VGA input)

I know how to not kill myself with flyback and all the funny things inside, so that's not a concern.

[helius]

For some reason, this question is coming up a lot, now.
What signal does your monitor use? I tried searching but got no results in a language I can read.
Normal VGA displays cannot display NTSC or PAL signals, the frequencies are out of range. The simplest approach I can think of would be making a "single line TBC" and turning the 60 fields/sec into 60 frames/sec with line doubling. The cheap Chinese upscalers may be using that approach.

[karoru]

Yeah it's normal VGA display, usually works in 640x480.

This model was quite popular years ago in Europe but information about it is pretty nonexistent, even in my native language most info I can see are protocols from some companies/government agencies about putting them into trash - looks like it was some random OEM company that offered them and went off business long time ago - I've never seen that brand at normal person's home, just commercial environment (mine was connected to some biological lab equipment, spectrophotometer or something like that)

Yup, thanks for pointing my brain fart - sync frequencies will be far off, it won't work as easy as B&W TV composite job:)
I'll try to play around with idea of making some homebrew upscaling, to the point I'd be sure I can't beat 20$ aliexpress scaler.

[helius]

The single-line doubling approach will work for most game consoles, since they have a vertical resolution of around 240 lines, and are not really using interlacing. But it won't work for real interlaced signals like video tapes; to de-interlace those you need to digitize a full frame.