Bad Colours with Super Famicom to Scart/JP21 RGB to XRGB2+

Hi everyone,

Need some assistance getting to Super Famicom working with the XRGB2+

The SFC to Scart cable has 220uF capacitors attached to the RGB lines.

I was unable to get a picture with the cable (it was scrambled)

So i made up a LM1881 Sync Stripper in the Sync circuit.

This gave a clear picture but poor colour and quite dark,

So I tried the THS7314 RGB buffer for the RGB lines with 220uf Caps on the input and 75 ohm Resistors feeding into the Scart connector.

I am also using a Scart to JP21 connector in series to the XRBG2+

I have tried playing with brightness and gamma controls on the XRGB2+ to little effect.

The RGB Buffer has improved the colour slightly but still seems quite dark the white level seems off too.

Any suggestions would be appreciated.

I have Sega Nomad with a Scart cable attached to the same XRGB and the picture and colour is perfect.

Cheers All

 

got any more pictures? it's hard to work out what's going wrong in that picture. like, the green is correct, the blue is correct, the yellow is correct... post some pictures of Super Mario World, or Zelda or something like that.

 

Have you tried another console?
The cable you described is correct for an SFC. It should have 3 x 220uF capacitors and nothing else in it (besides a 5V RGB toggle connection, possibly with a resistor bridging pin 8 and 16 in the SCART end).

 

i guess your feeding the syncseparator with composite video? wath if you skip the sync separator and connect clean c-sync on the famicom end? iv had ptoblems on some screens with compsitvideo on the sfc

 

Hi all,

Thanks for the responses so far

please see attached screen shots from mario and the konami screen,

Yes Oakleaf without the LM1881 Sync Separator the screen was scrambled.

The colours seem too bright and vibrant, while the white level seems grey

I'm thinking that the output from the super famicom is too high but it seems strange that other consoles (sega) that I use on the XRGB dont have this issue.

 

I would first replace the capacitors in the cable. Could be the cap on red is dodgy.

 

Hey everyone,

I've fixed the problem for future reference I didn't have a good ground connection between the cheap av connector and the scart connector.

re terminating the gnd connection and added a few more on the scart connector fixed the problem.

Thanks all