Sengoku Blade color issues - Washed out blacks

[oneleaf86]

I've had this Psikyo PCB for a while now decided to dig it out of my stash to try and get to the bottom of the issue.

The game plays 100% but something's not right with the video output as you can see in the attached images.

If anyone has any insight as to what could be causing this issue, I'd love to hear from you

 

[nem]

What happens when your turn down brightness and / or contrast? The left hand side of the color bars look far too bright.

Different games have different video outputs. I need to regularly tune brightness for different boards.

 

[oneleaf86]

What happens when your turn down brightness and / or contrast? The left hand side of the color bars look far too bright.

Different games have different video outputs. I need to regularly tune brightness for different boards.

This is definitely not a brightness issue. By the time I've turned the brightness down to the point in which the blacks actually look black, the game is extremely dark.

Looks the same on my Astro City as well. There's a fault on the PCB somewhere but I just don't really know where to look.

Thank you for the suggestion though!

 

[XianXi]

Looks like a gain issue like a bad amp/transistor.

Trace back the RGB lines from the edge and take note of what they are connected to and post back.

 

[oneleaf86]

Thanks for the suggestion. The first thing I suspected was one of the NPN transistors so I replaced all of them which didn't fix the issue.

Also tested all of the resistors. Thinking it might be the palette RAM?