Weird image issue with Dreamcast when outputting 480p

[RebeL9]

So I’ve finally been able to borrow the scart cable from Retro Gaming Cables that have a switch for 480p.
I’ve hooked up my US Dreamcast to my BVM D24 through an Extron Crosspoint but I get this weird issue with the top half of the image.
This only happens on Dreamcast. None other of my console got this issue.
Is there any way to solve this?

[Dreamcazman]

It could be something to do with the way the cable converts RGHV to RGBS and maybe the BVM doesn't like it.

Have you tried a proper VGA box and a monitor to confirm the DC itself is ok. I'd say it will be.

Are you able to connect it as normal 15KHz RGB to test?

You can try adjusting the geometry but that will probably affect everything else too.

[Jockel]

I have the same cable and experience the same issue on my D20. So it's not just you.

[Kez]

Yeah this is a known thing with the DC and D series.

You can fix it by running the signal through an Extron RGB with the SERR dip switch. Retro Access' Dreamcast SCART cable also has some circuitry (designed by Dan Kunz/citrus3000psi I think) which prevents this from occurring.

[RebeL9]

Yeah this is a known thing with the DC and D series.

You can fix it by running the signal through an Extron RGB with the SERR dip switch. Retro Access' Dreamcast SCART cable also has some circuitry (designed by Dan Kunz/citrus3000psi I think) which prevents this from occurring.

That makes it even more obvious that I must find the Retro Access cable :S

[Kez]

Yeah this is a known thing with the DC and D series.

You can fix it by running the signal through an Extron RGB with the SERR dip switch. Retro Access' Dreamcast SCART cable also has some circuitry (designed by Dan Kunz/citrus3000psi I think) which prevents this from occurring.

That makes it even more obvious that I must find the Retro Access cable :S

If you can't get that, since you're running off a crosspoint it wouldn't be too tough to add an RGB interface to the chain and could add a few other benefits too (like image centering).