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Velyks

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I'd like to make a generic Versus Kit for JAMMA games, something like a small(ish) board that plugs into the game and then plugs into two jamma harnesses to allow one game to span two cabs.

As part if this I'd like the audio and video to be fully buffered rather than trying to get the game to power both displays. I have a basic knowledge of electronics but I'm not sure where to start when it comes to designing a video buffer circuit for arcade voltage level video, would anyone be able to give me some advice?

Ideally I'd like to run it from the 5v and 12v provided by one of the cabs while ignoring the -5v as I almost never see it hooked up.
 
You can have a look at the video buffering and audio isolation circuits I used for betsubetsu.
https://www.arcade-projects.com/for...o-video-splitter-for-capture-streaming.10551/

There's a link to the Kicad project in the main post.
Thanks, this might actually work though I'll probably be operating at the limits of that IC as I'm not going down to 75ohm terminated video. Will give it a test.

Edit: Read more through the data sheet, the max input voltage for the THS7374 is about 3.5v so it wouldn't be suitable :(
 
Attenuate the signal upon input ;)
 
It would remain a buffer. If you didn't attenuate the input you'd be outputting double the jamma voltage.
 
You can have a look at the video buffering and audio isolation circuits I used for betsubetsu.
https://www.arcade-projects.com/for...o-video-splitter-for-capture-streaming.10551/

There's a link to the Kicad project in the main post.
Thanks, this might actually work though I'll probably be operating at the limits of that IC as I'm not going down to 75ohm terminated video. Will give it a test.
Edit: Read more through the data sheet, the max input voltage for the THS7374 is about 3.5v so it wouldn't be suitable :(
Uh. Jamma video signals are about 3V max peak to peak, and the circuit I linked does AC coupling.

What would it not be suitable for?
 
you can clamp the sync signals with resistors and zener diodes.
RGB on arcade boards can be upto 3v, on tv's and other similar stuff it's often as low as 700mV
 
The circuit I linked buffer sync after a resistor voltage divider + AC coupling.
 
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