Sega Naomi 1 in Astro City?

ZODIAK

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Hello!
I've seen this questions answered several times, however I would just like some updated information.

- In the past, there has been discussion of the Sega IO/Capcom IO having display issues, added lag and general washed out colors when on an Nanao MS8. Is this still true?
- How are the colors when using the TD-IO? I've seen this solution posed before however I haven't seen any follow up on if this adds any lag or if there are any display issues.
- Similar question for the Chinese IO found here https://www.ebay.com/itm/364454394508, how does this compare to the TD-IO in terms of usability/lag/color display? I am aware that the IO will need to be modded and a separate adapter is needed for the kick harness as well.
- Final question, how is power usually handled? I've seen many solutions involving desktop PSUs to handle power before, however I don't see how this can be plugged in to the cab without drilling a hole through the back or running through the coin door? is there a way to power a Naomi 1 with Netdimm using the Astro City PSU, or will something like the NVS-4000 be required?

Thanks!
 
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TDIO is the gold standard now. No reason to go with anything else. No lag and video is fine in cabs I have tried it on. 3.3V is converted from 5v rail from your existing PSU.
 
TDIO is the gold standard now. No reason to go with anything else. No lag and video is fine in cabs I have tried it on. 3.3V is converted from 5v rail from your existing PSU
Ah I see, so the power can be handled by the TD-IO as well? Will any power connections still need to be made to the Naomi board itself? I haven't seen a clear view of how the TD-IO is wired up in an Astro before, hoping its just plug and play.
 
Capcom I/O can also power the Naomi. It has around 1.5F variable input lag, but the reality is that many people have used it for many years in competitive settings and I have never heard an actual complaint. AFAIK, the Sega I/Os do not add a significant amount of lag.

I haven't heard anything regarding video quality issues, so you may be conflating this with some of the video funk related to the early revisions of the "Rev 1" Sega I/O. The "Rev 2" (in the metal box) don't have this problem, and you can find Rev 1s with an improved video circuit (look for an attached daughterboard). In general, Naomi looks like pond water in 15K so you might be splitting hairs if I'm being honest. Rev 2 can power Naomi, Rev 1 cannot. Neither of these I/Os (Capcom or Sega) can power a GD-ROM setup, you need external power.

I would not mess with any Chinesium I/O boards. Nobody really knows what the heck is going on with those.

For external power, you can use ATX, Sun PSUs, Mean Well, plenty of ways to solve the problem. You don't need it unless you're gonna use a GD-ROM, CF, WiPi etc. td-io can handle it but the IC on the power circuit can experience thermal shutdown so you probably want to put active cooling on the board to solve for this.

You can route whatever you need through the 30mm hole plug behind the cab on the plate with the power switch and the mains wiring. Some people (leonk, search for his posts) have wired in power strips to the mains wiring so you don't have to run anything extra out of the cab.
 
The MS8 in your Astro (much like the MS9 in New Astro City) is only a 24khz/15khz monitor. Sega Naomi native resolution is 480p/VGA/31khz.

There's a dip switch on the Naomi to switch it to 480i to run at 15khz, but interlaced image on such a big CRT, so close to your face has a negative effect on many people. That's where the bad image / blury image comes from. There is no added lag from using any of the I/Os. None of them have a frame buffer, just simple amplifiers and signal/noise reducers.

If you want to continue using a 31khz native arcade PCB, in a 15khz/240p arcade machine, the best solution is the UVC (Ultracade Universal Video Converter) This device cleanly converts 31khz/480p to 15khz/240p with 0 lag, giving you a crisp progressive scan image on the CRT. The only flaw with the UVC is that it hasn't been made in 20+ years and goes for $$$ today whenever one comes up for sale.
 
The MS8 in your Astro (much like the MS9 in New Astro City) is only a 24khz/15khz monitor. Sega Naomi native resolution is 480p/VGA/31khz.

There's a dip switch on the Naomi to switch it to 480i to run at 15khz, but interlaced image on such a big CRT, so close to your face has a negative effect on many people. That's where the bad image / blury image comes from. There is no added lag from using any of the I/Os. None of them have a frame buffer, just simple amplifiers and signal/noise reducers.

If you want to continue using a 31khz native arcade PCB, in a 15khz/240p arcade machine, the best solution is the UVC (Ultracade Universal Video Converter) This device cleanly converts 31khz/480p to 15khz/240p with 0 lag, giving you a crisp progressive scan image on the CRT. The only flaw with the UVC is that it hasn't been made in 20+ years and goes for $$$ today whenever one comes up for sale.
Interesting, this UVC converter, is it this? https://www.ebay.com/itm/376635812493 I see it has a molex connector for power and a vga input, I'm assuming this particular listing is missing the jamma connection but this would be the best way to convert a 31khz signal into a 15khz monitor? Theoretically, this could also work with other boards like the Ringedge 1, is that my understanding? Since its a line doubler and outputs at 240p.

Also another question, if this UVC is used, how would inputs from the Jamma connection be handled? I don't see a section of this for JVS controls like I do on other IOs, going to assume that an IO will still need to be used to handle input, then this will handle video?
 
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Capcom I/O can also power the Naomi. It has around 1.5F variable input lag, but the reality is that many people have used it for many years in competitive settings and I have never heard an actual complaint. AFAIK, the Sega I/Os do not add a significant amount of lag.

I haven't heard anything regarding video quality issues, so you may be conflating this with some of the video funk related to the early revisions of the "Rev 1" Sega I/O. The "Rev 2" (in the metal box) don't have this problem, and you can find Rev 1s with an improved video circuit (look for an attached daughterboard). In general, Naomi looks like pond water in 15K so you might be splitting hairs if I'm being honest. Rev 2 can power Naomi, Rev 1 cannot. Neither of these I/Os (Capcom or Sega) can power a GD-ROM setup, you need external power.

I would not mess with any Chinesium I/O boards. Nobody really knows what the heck is going on with those.

For external power, you can use ATX, Sun PSUs, Mean Well, plenty of ways to solve the problem. You don't need it unless you're gonna use a GD-ROM, CF, WiPi etc. td-io can handle it but the IC on the power circuit can experience thermal shutdown so you probably want to put active cooling on the board to solve for this.

You can route whatever you need through the 30mm hole plug behind the cab on the plate with the power switch and the mains wiring. Some people (leonk, search for his posts) have wired in power strips to the mains wiring so you don't have to run anything extra out of the cab.
This is all great information, Thanks! I'm particularly interested in this solution @leonk suggested, but in the long term I may just get a New Net City for all my JVS needs.
 
Interesting, this UVC converter, is it this? https://www.ebay.com/itm/376635812493 I see it has a molex connector for power and a vga input, I'm assuming this particular listing is missing the jamma connection but this would be the best way to convert a 31khz signal into a 15khz monitor? Theoretically, this could also work with other boards like the Ringedge 1, is that my understanding? Since its a line doubler and outputs at 240p.

Also another question, if this UVC is used, how would inputs from the Jamma connection be handled? I don't see a section of this for JVS controls like I do on other IOs, going to assume that an IO will still need to be used to handle input, then this will handle video?
Give this a read: https://www.emphatic.se/ultracade.html

Emphatic wrote this a long while ago but it has all the info you need. He’s is one of the earliest guys to really put the UVC through its paces.
There’s many applications for the UVC. You can wire it into a Jamma adapter like shown on his site to get the signal fed to the video pins on the Jamma connector.

I mainly use it for Naomi downscaling like mentioned above. I built mine into a Sega IO Jamma stack.
IMG_7227.jpeg
IMG_7229.jpeg

I use the Jamma IO and connected a JNX Atlas adapter which allows me to easily tap power for the UVC, and get the kick buttons from the IO on a CPS2 kick connector.

IMG_7212.jpeg


IMG_7223.jpeg

RGB from the UVC is plugged into the IO so it goes out of the Jamma edge.
IMG_7224.jpeg


makes it easier to plug into and have sitting organized in the cab.

Naomi games look amazing in 24khz on a Nanao.
IMG_4681.jpeg
 
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Figured I would update this thread, this issue has been solved! I actually ended up getting a Capcom Mini Cute instead of an Astro, but I went with the TD-IO route. The result was very easy to setup and pretty much plug and play. In the future I hope to get an Astro but for now this works well for my space. Thanks for all the help!

minicutemahvel.jpg
 
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