Bubble Bobble tech question

[rmg_uk_73]

I recently acquired an original BB board, but noticed it has colour issues. There's seems to be an excessive amount of intensity of colour affecting the whole game- leading to bub looking anemic (really light blue), monsta's looking pink rather than blueish purple and the orange border surrounding the title screen logo yellow as opposed to orange (amongst numerous other problems). The thing is this isn't the only Taito board i've had this particular problem with; another bb and a Tokio pcb are also afflicted with the same fault. Seeing as it's highly unlikely they've all gone tits up with the same thing I think my jamma adaptor is to blame, yet it matches the pinout.

Any ideas?

Cheers.

Edit: Checking the harness on my supergun reveals that video ground is completely unconnected, could this be the problem?
rmg_uk_732006-05-10 00:21:02

 

[easternpinman]

rgb ground is very important,,,,,,,,,!!!!!shoul be connected

adjust the colors from Your monitor not all boards have the same setting this is more because of the different output RGB level