Help with RGB to NTSC Converter

Twin Paradox

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I recently found a free street fighter 2 arcade cabinet on craigslist. The original pcb was inside but it appears the guy had tried to convert the arcade into a mame machine and quit halfway through. He replaced the the original monitor with a de-cased television. I want to restore this machine to a street fighter 2 but I don't have the money to buy an arcade monitor.

That brings me to my point. Instead of buying a new arcade monitor, I instead bought an RGB to NTSC encoder so that I could display video from the street fighter pcb to the television. My only problem is that I have no idea how to wire it up. The encoder came with no instructions, there are no instructions on the website and no one at Jamma Nation X has responded to my numerous emails. I have tried to take enough pictures so that some of you knowledgeable people might be able to lead me in the right direction.

Oh and just FYI, the adapter comes with an s-video and an rca jack. I am planning on using the s-video jack (which is why I included that in the pictures)
 

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It probably would have been less work to find a Arcade monitor chassis that would work with the tube.

That said, I believe the owner of Jamma Nation X Xian Xi, is an active member of the Neo Geo forums, so you may have luck if you post over there.

I could have sworn he was a member here as well though I don't know his username.

I will take a wild guess here: I would imagine the wires are red green blue for their respective color signals, white should be horizontal or composite sync, brown should be vertical sync which is used by some older PCBs and black is your ground.
 
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the wires are red green blue for their respective color signals, white should be horizontal or composite sync, brown should be vertical sync which is used by some older PCBs and black is your ground

have to have +5 volts going in to power the chip(s)
 
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That PCB seems to be an implementation of Sony encoder (CXA1645 or the newer one) and it is used most commonly in the game consoles of the 80-90's (i.e. Sega Master System).

Having said that, the outputs of this circuit would probably be;

- RGB (pass thru)
- Composite video
- S-video (luma+chroma)
- etc

Your video will look like s**t unless the TV in the cabinet is a quality one or a Sony PWM monitor. If you have to, use the S-video if your TV supports it.

At this part of the world we do use TV's in our cabinets because we have SCART (Native RGB input) and the video quality is always better than a beaten up arcade monitor.

I also would recommend an arcade monitor OR try to tap into the RGB lines of the TV chasiss rather than using that encoder... All the TV's in the world somehow convert their input signal into RGB somewhere in their electronic circuitry...

Good luck
 
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