I have an Atari 2600 and a Sinclair ZX Spectrum, fully working.

I want to connect them to a standard PC monitor, which seems to be a particularly good idea as I have also handy a very good up-scaler:
XRGB-mini Framemeister

So, I only need to convert the "antenna" audio/video output of the two old machines (which is physically an RCA connector) to
either
S-Video + RCA Audio L+R (well, these are mono devices...)
or
RCA Video (yellow) + RCA Audio L+R

How? I can't seem to find such a converter. Yet, that's something any old (and new) VHS VCR could easily do! I really do not want to use an old VCR for that only. I am hoping to simply find a small box that lets me do that.

Do you guys have any suggestion?

Are there (or were, back in the day) modifications that brought out the raw video signal(s)?

It sounds like these machines are delivering a modulated TV channel output signal, and what you needs is just the original video signal from inside the game console, prior to the RF modulator.

Edit: Like this.

Yes, they are delivering a modulated TV channel output. And there are hacks.

But, I was really hoping to keep these machine pristine and not hack them.

The thing you want is called a UHF demodulator.

Peter

THANK YOU!

That box won't work, it only goes down to 467MHz. You'll want something that can demodulate down to 54MHz.

Ohhh, were Atari 2600s VHF-only? ZX Spectrums are certainly UHF (channel 36).

Googling it a bit seems to suggest that 2600s were UHF in some markets and VHF in others. That box will only work on UHF, but at least now you know what to search for...

Peter

My 2600 (US version) worked on channel 2 or 3 (54 or 60MHz). Same for the NES when using the "antenna" option.

Same with my Sega Master System. I'm not sure how I'd hook that up these days. I guess I'll have to get one of those devices too...

I could not find any VHS DEmodulator.

Anyway, I got a UHF demodulator all the same, just in case and to keep one in the house (I have other old less popular videogame consoles).

I do not know yet which channels the Spectrum and the Atari are using. I'll check on a TV and keep you guys posted as I progress with this fun retro-gaming thing


P.S.: If anyone is more successful then me in finding a VHS demodulator, please let me know! Thanks again guys!

I forgot the different Ataris transmitted on different channels, in the US they were channels 3/4.

Here are some demodulators that should work:

Link

Link

Link

Thank you!
I'll see if I can find them here in EU.