shaky dreamcast graphics.

[spottydog]

Hello, when I run my dreamcast on my cab, the graphics are shaky.
I adjusted horizontal and vertical hold but these actions did not solve the problem.
The entire image shakes and this shaking is constant in all of the games I've tested aside from three. The three are the Street Fighter 3 games.
In those, there is shaking when they start (Dreamcast logo...) but it stops entirely after the memory card is loaded. At that point, the image is perfect.

Any ideas? There isn't a -5V wire on my harness, could that be causing the problem?
                          thanks

[Glaine]

I was thinking maybe you should fiddle with the video plug in the dreamcast, pull it out a little or push it in a bit more but if it plays fine once the VMU loads then I don't know. I'm only suggesting the above cuz I had a PSX that did that and I think dreamcast uses a very similar vid cable connection.

[Minwah]

The three are the Street Fighter 3 games.
In those, there is shaking when they start (Dreamcast logo...) but it stops entirely after the memory card is loaded. At that point, the image is perfect.

Remember some games can run at 60hz, but the logo is always @50hz.  It sounds to me like your screen is setup ok for 60hz, but is struggling at 50hz.  Many games have the option to set to 60hz - have a look into it...

That said, you should be able to adjust the v-hold until the 50hz picture is OK.

[Glaine]

Thats a very good point, I don't know how to adjust that, but I've heard the DC-X import loader disc can display 50hz games in 60 and vice versa.

[spottydog]

Hi, I tried your suggestions but they didn't solve the problem.
My dreamcast to jamma unit connects to a jpac. I ran Soul Calibur and the 'SYNC OK' LED on the jpac flashed repeatedly very quickly.
The problem may be due to the wiring. I have removed the original jamma harness and installed another in my cabinet. I found that task difficult.
If I connect the ground wire to 'ground' on the power-supply, there are waves of lines on the screen when a Mamewah game runs.
But, if I connect the ground wire to front ground on the power supply, Mamewah runs perfectly and the image is ideal.

 

[Glaine]

You didn't say you were using a Jamma hooked dreamcast, that I'm sure has other issues of which I can't help. Try to find the jamma pin print out for your machine and make sure they match your adapter?