I’m not sure if my question aligns with the themes of this forum, but perhaps I can get a hint from you on a solution. Please also let me know if you know somebody or a better website where I can find the support I’m looking for.
I own a retro PC Robik created around 35-37 years ago.
I’m looking for help with building a converter from CSYNC+RGB signal into a regular composite PAL video.
I have the following schematic, which has been proven to work with the retro PC I have, but it produces S-video output. I believe it should be possible to output RCA video from this converter, too.
I don’t have much experience in building such modules, and I thought that it would be nice to find a hobbyist who would be interested in assembling the converter for me. I’m happy to pay for work, components and delivery. I’m ready to provide oscillograms of the required signals.
Please let me know if you or somebody you know can help me with this project.
What a fascinating project, it’s always great to see vintage hardware like the Robik getting some love. Wishing you the best of luck with the restoration and video conversion! Hopefully, someone with the right tools and interest reaches out soon.
If you’re tinkering in the meantime, you can create a simple composite-style output from RGB + CSYNC using a resistor-capacitor network to blend the channels. It’s not as clean as a proper encoder, but it can work in a pinch!
Hi Steady
Pushing the memory bank here.
I think that “X3” at the top of the schematic is “Composite video”. It originates from pin 20 which is marked “CVout” which I believe is Composite video as usually found on the yellow RCA connector.
I think from memory the difference between Comp video and S Video is just the connector. “Comp Video” is RCA and “S Video” is a small mini Din style multi pin connector.
Cheers Bob
I agree that either CVout or Yout should be a composite output.
I also found this schematic of another converter, which claims to be able to output DVI over an HDMI jack.
It would be pretty exciting to be able to output directly to HDMI! It would resolve any connectivity issues, as all modern monitors and TVs support HDMI. However, RCA would be fine too.
I’m looking for different options and will post an update if I find a working solution
