Connect JAMMA RGBS to RGB sync-on-green for Morph 4K scaler (or PVM)

brandogg

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Hello! I want to be able to hook up a JAMMA PCB (namely Mortal Kombat 4 at the moment) to either a scaler (I have a pre-built GBS-C and a Morph 4K with RGB analog bridge) or to a Sony PVM. Either way SOG would be preferable since it would work for either setup (the analog bridge doesn't support ext sync). Does anyone know what I would need, hardware-wise to adapt the RGB signal to something that any of these setups would support? I can likely buy any of the needed components locally (cables, resistors, pots if needed). The end goal is to be able to capture crisp clear footage from the PCB (I have a capture device) so it can be used to compare the original hardware against the MK4 MiSTer core to help out the developer of said core. I do already have an HD VC-9900 so technically I can get footage, but that thing is basically trash and does a horrible job scaling. Thanks for any help! Also I have the power supply and all that good stuff, the only thing I need to do is fet the video signal properly formatted/attenuated/sync converted so I can use a scaler.
 
Actually I just realized this is probably better suited for using RGBHV so these are probably the correct instructions (both of my scalers have DB-15 inputs that can support RGBS)...does this seem legit?
 

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So, that worked. I guess I'm not exactly reinventing the wheel here, but this is what I built. I can now feed my JAMMA PCBs directly to my Pixel Morph 4K and then play on any TV or record footage with OBS (which is what my goal was). Oddly I do have to choose RGB (HB/S) TTL sync levels on the morph, even though I put a 470ohm resistor on red, blue, green, sync (pin 13), I would have thought RGB(S) 75 ohm sync levels option would work...maybe I'm just misunderstanding how the analog bridge works.
 

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