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Need some help with Ninja Assault

Franco23444

Franco23444

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Hello everyone! I finally got my first Sega Naomi arcade system! The first game I got with the system is Ninja Assault. Now, I want to know if there’s a way or work around to be able to play this 31khz game on a 15khz crt? I don’t own any 31khz CRT computer monitors or have a CRT tv with 480p support and I don’t plan on getting any (low on space and prices can be a bit ridiculous). Is there a way I could play this game in 15khz, say downscale it to 480i or 240p? I tried the dip switch to put it in 15khz and it does nothing. I need a bit of advice and/or help!

Edit: it does play in 15khz but it uses HV sync instead of C sync. Is there a device or a way to combine the sync to probably play on a 15khz crt?
 

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I use an extron 109xi to play TC3 on a pvm, which had the same issue outputting hv but needing c sync. It works as long as all the sync processing options that the box offers are off
 
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ekorz said:
I use an extron 109xi to play TC3 on a pvm, which had the same issue outputting hv but needing c sync. It works as long as all the sync processing options that the box offers
Click to expand...
I might look into that, the Namco System 246 uses C sync in 15khz, which is how I’m able to play all of my light gun games on my 32” 15khz consumer CRT tv. Ninja assault is kinda weird as it still uses HV sync. I still don’t have the extra HVBUFF pcb and I’m not sure if it’s an essential part to be able to play this cool looking game.
 
I've got the HVBUFF pcb, and to me it just looks like it splits the sync signals out to the IO board.

If you've got a different gun board that works (maybe a rays PCB or a TC2/3 crt style one) then you won't need that.
 
Franco23444 said:
I might look into that, the Namco System 246 uses C sync in 15khz, which is how I’m able to play all of my light gun games on my 32” 15khz consumer CRT tv. Ninja assault is kinda weird as it still uses HV sync. I still don’t have the extra HVBUFF pcb and I’m not sure if it’s an essential part to be able to play this cool looking game.
Click to expand...
Well that extron unit is cheap and it works.

And from what I recall even though the 246 docs say it outputs RGBS, TC3 in particular was sending HV regardless of the dips or anything. I think namco sold a sync combiner board but I didn’t have that (this?). I could also send video through a namco jvs io to get it to work, but that dimmed the picture too much, so I figured it was also reducing the video voltages.

https://www.arcade-projects.com/threads/time-crisis-3-contrast-sync-solved.8270/#post-137241
 
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bobbydilley said:
If you've got a different gun board that works (maybe a rays PCB or a TC2/3 crt style one) then you won't need that.
Click to expand...
I might try using the Time Crisis 3 I/O board and see what happens, the Naomi, specifically with this game doesn’t seem to recognize the Rays pcb. I guess that it’s incompatible with this game.
Looking in the manual, I think the HVBUFF PCB looks like it connects to the JYU pcb and taps into the sync signal so the guns can register. Time Crisis 1’s GUN DRIVE pcb has the same sync chip on the board, but that games uses C sync and the Gun Drive board is optional.
ekorz said:
Well that extron unit is cheap and it works.

And from what I recall even though the 246 docs say it outputs RGBS, TC3 in particular was sending HV regardless of the dips or anything. I think namco sold a sync combiner board but I didn’t have that (this?). I could also send video through a namco jvs io to get it to work, but that dimmed the picture too much, so I figured it was also reducing the video voltages.

https://www.arcade-projects.com/threads/time-crisis-3-contrast-sync-solved.8270/#post-137241
Click to expand...
well, I will give the extron a try. My Time Crisis 3 pcb works fine with my Namco converter. My ninja assault on the other hand produces a scrolling black and white picture when I try to use my converter and I suspect that it’s because of the HV sync issue. Hopefully combining the sync to C sync will solve that issue.
 
If you get the extron, try taking the namco jvs io out of your chain and using it there too. I bet you the video looks way better…
 
I tried using the time crisis 3 I/O board, it also doesn’t boot with it. The system throws an I/O pcb Error. I bought an Extron 109xi and I’ll see what happens.
 
Well, I finally got around to testing the Extron unit and it doesn’t seem to work with 15khz output, I get a black screen. 31khz output works great and actually does combine HV sync to C sync. Got to find another solution. Kinda disappointed but I will keep on searching.
 
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I actually tested my other arcade systems and 480i and 240p work flawlessly with the Namco system 246,256,11 and 12. For some reason, the Extron doesn’t like my Naomi in 15khz mode. I’m not sure if it’s due to the sync or what. The Namco hardware output C sync from the start. Weird.
 
Can’t say I tried it for Naomi but I’ll check when I have the gear back. you’re sending the signal straight from the Naomi to the extron, and all the sync processing is off?
 
ekorz said:
Can’t say I tried it for Naomi but I’ll check when I have the gear back. you’re sending the signal straight from the Naomi to the extron, and all the sync processing is off?
Click to expand...
I tried with RGBHV, RGBS and RGsB with DDSP on and off. Nothing shows up through the output side. The front “bypass”vga shows the video signal in both 15khz and 31khz HV sync but nothing on the BNC outputs. Every other system is ok.
 
Update: 08/23/2021. I was finally able to play this game using a new converter that I have found. I’m able to use component video inputs instead of S-Video or composite and the image quality is near perfect to a real RGB arcade monitor. I was able to play the game in 15khz mode on my 32” JVC CRT tv. The converter I found for around $50 is pretty awesome and converts both VGA(RGBHV) and RGBS to YPBPR. If you would like more information on the converter I used, let me know!

View: https://youtu.be/xH_JxQe7Pzk
 
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