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grendelrt

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I like to hook up my Naomi to my Blast City via UVC when playing MvC, CvSNK, etc for 15khz vs the built in interlaced 15khz. Been testing\searching for a solution and haven't found one but found some similar issues. The UVC connection looks like, Naomi VGA set to 31khz -> UVC via VGA, UVC -> Capcom IO by dummy jamma fingerboard connect to UVC video via wires. Here's what I know so far:

Naomi 31khz -> Blast City via VGA bright vibrant picture
CPS2 Jamma 15khz, MVS Jamma 15khz, GroovyMame PC VGA 15khz/31khz-> bright vibrant picture
Naomi VGA 31khz-> UVC set to 15khz or 24khz out via jamma fingerboard-> Blast City -> very DIM, max out brightness on monitor still dim vs others
Tried masking off with kapton the video signal jamma connections on the capcom IO to make sure the fingerboard that i use as passthrough doesn't bleed off to the IO

UVC was made for arcade monitors so I am assuming it outputs the correct TTL? Is it something to do with the TTL on the jamma connection vs the VGA connection, maybe VGA takes multiple TTL but jamma only takes one value and UVC is incorrect?
 
What UVC firmware version do you have? what are your dip switches currently set to? Are you able to show pictures of the connection between the UVC and Capcom I/O board?

I have a UVC in my NAC, but it's feeding to a Sega JVS to JAMMA PCB and I don't have the issues you describe. I have the wires from the UVC soldered right to the JAMMA edge connector on the JVS adapter and no other video feeds into it. It does have the JVS pluged into it for controls. Worst case, can you take the capcom out and just connect video only? I know you won't have controls, but at least a test to make sure the capcom I/O isn't sinking your video signal.
 
What UVC firmware version do you have? what are your dip switches currently set to? Are you able to show pictures of the connection between the UVC and Capcom I/O board?

I have a UVC in my NAC, but it's feeding to a Sega JVS to JAMMA PCB and I don't have the issues you describe. I have the wires from the UVC soldered right to the JAMMA edge connector on the JVS adapter and no other video feeds into it. It does have the JVS pluged into it for controls. Worst case, can you take the capcom out and just connect video only? I know you won't have controls, but at least a test to make sure the capcom I/O isn't sinking your video signal.
Its PCB-03, connection is to a fingerboard with a female back\male front that sits between the capcom io jamma and the blast city jamma. I tried putting kapton tape over the capcom io contacts that are in the same spot as the video out on uvc to try and prevent the sinking, but I will try it with the IO completely out of the equation as you suggested, that's a good idea just to rule out the IO connection in general.
 
PCB-03 means nothing. If you disconnect the video input into the UVC, you should see the UVC intro menu; it will tell you the firmware version there. Can you share the dip switches on the UVC? I can compare to mine.
 
PCB-03 means nothing. If you disconnect the video input into the UVC, you should see the UVC intro menu; it will tell you the firmware version there. Can you share the dip switches on the UVC? I can compare to mine.
PCB 03 means its one of the last 2 iterations,
· Version 03A. PCB version 03. Firmware version 2.04: 07/01/2004, DT. PCB allows multiple clock footprints. Firmware has increased functionality.
· Version 03B. PCB version 03. Firmware version 2.1: 05/11/2005, DT. Fix intermittent sync problems from some consoles and DIP switch

Ill check which one next time i turn it on on the splash. I have all the dips in stock, which is all on except the last dip.
 
Progress! I confirmed by removing the Capcom IO and only hooking the UVC up to the jamma m\f adapter the picture looks bright and normal. I tried re doing the kapton tape on the capcom IO connectors and the best I could get was the picture dimmed only on red, but it still dimmed. I think that fingerboard is just making connection regardless of the tape. Guess my next step is to redo the fingerboard and try cut away the connection from the male side to the female side and see if that helps.
 
Glad you figured out the issue is the capcom I/O. Another option is to buy a Sega JVS to JAMMA converter (should be much cheaper than than a Capcom I/O and you can sell the Capcom) The only downside is you'll need an external PSU, but I was never a fan of the Capcom PSU. I have a Naomi 2 setup, and the Capcom I/O can't generate enough juice - Using a SUN PSU (which is basically a PC PSU - you can modify a new PC PSU to power everything) can generate a lot more current to keep all the connected devices happy.
 
Fully rebuilt the jamma adapter for the UVC and cut all video connections that would go to the IO, fully fixed now :) It looks glorious.
 

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