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RGB (VGA, JAMMA, etc...) Splitter Board

DragonMinded

DragonMinded

Professional
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Location
Chelsea, VT, USA
I've been hard at work adding VGA-level RGB outputs to the back of my cabinets in order to stream them to friends with no fuss. Most of my cabinets that I want to stream are non-JAMMA so the existing JAMMA-based splitters such as the NAC Splitfire weren't an option for me. Besides, I hadn't built a PCB in awhile and was feeling the itch :rolleyes::thumbsup:. So, I've spent the last few months (and four PCB revisions) hammering out the details on a VGA form factor RGB splitter board. I've already got several installed in my games but when I get the energy I add a VGA and 1/8" audio jack to the back of another cabinet and wire in a splitter board. These are perfect for splitting VGA signals commonly found in cabinets like older Vewlix and NNC cabinets.

Here's a copy-paste of the features from the manual I put together. If you want to read the whole thing and see pictures, you can look at the manual here: https://dragonminded.com/arcade/partsales/streaming-manual.pdf

• Zero lag splitter which does not affect the source signal in any way.
• VGA-compatible RGBHV splitting which can feed a secondary VGA monitor or a VGA-compatible capture device.
• OSSC-compatible RGBHV and RGBS splitting which can attenuate arcade video signals to safe levels for plugging into the AV3 input of an OSSC.
• SCART-compatible RGBS splitting which can be used with SCART-to-VGA cables for plugging into the AV1 input of an OSSC.
• Unity contrast knob for adjusting video attenuation in situations with non-standard voltage levels such as JAMMA.
• Individual gain pots for fine-tuning color adjustments to account for variations in source signals in the case of JAMMA capture.
• Can be powered from a USB cable, external 5V power such as a 5V JAMMA wire or even from pin 9 on VGA when it is present.
• User-selectable sync buffering which allows for TTL-level horizontal/vertical and composite sync, as well as 75Ohm terminated composite sync.
• User-selectable low-pass filter on RGB lines when interfacing with RGB-modded consoles.
• Passthrough VGA port which includes EDID pass-through for VGA signals.
• Solder points for attaching spliced RGBS or RGBHV signals and power for custom installations.

I did a small run for myself and I have boards up for on-demand sale on my web site. Is there any interest to doing a larger batch order for here? I'm asking $80 shipped in the US (covering all fees) and can offer discounts for multiples since the shipping is a fixed cost. I think I can get these shipped overseas this time around if I send them as first class postage. Last time I tried shipping to a friend in Australia and a small flat rate box was $55 and it took them almost a month to deliver it so I won't be using that anymore. If I can figure out a reasonable way to ship these I will ask $10 shipping surcharge for each package that I send out and if it turns out to be impossible or stupid expensive I'll give you an option to refund or pay the extra (whatever shipping costs minus $10 which I'm good for and the $10 you already paid as surcharge, so minus $20 altogether).

If there's sufficient interest I'll send in an order for a batch of PCBs and send in an order for the parts. When they're all assembled and tested I'll contact everyone to take payment and start shipping out. I'm not going to ask for money until they're ready to go out. Please don't sign up for one and then ghost me when it comes time to get payment. I had that happen on my run of Monkey Ball PCBs and barely broke even on them making it incredibly not worth it for me to even bother. If you're interested, reply to the thread with how many you want and your approximate location (IE, US, Canada, Australia, etc...) and I'll update the thread so you know I got you accounted for. If you are curious about feedback, check out my NNC remote board thread and ask one of the people that got one from me there: https://www.arcade-projects.com/threads/for-sale-new-net-city-extended-remote-boards.16560/
 
Id be interested in this... Im eyeballing a handful of jamma video splitters... To find the cheapest solution that works for me. Ill check your website though if theres no interest here
 
Hmm... how did I miss this?

I've been looking for a solution like this in to install in all of my cabinets for awhile now. Right now I have been manually wiring in Tim Worthington's AV driver PCB for a handful of my cabinets and it works decently...but it's a pain to install since it's all manual wiring. He recently released a new device called the SUPATT (https://etim.net.au/shop/shop.php?crn=219&rn=579&action=show_detail) that looks to be a much cleaner solution. I was planning on biting the bullet and buying a bunch of his devices for installation in all of my cabinets, but I was hoping there might be a cheaper/better device. Yours looks like it would be the better, lower cost option, but then I saw your asking price...

Tim's device is $60 (and yeah I know he's in Australia so shipping prices...) and your device is $80. I think your device would be a lot more tempting if it was priced accordingly. Just saying. Of course you put in the work to engineer and build your device and you have the absolute right to set your own prices. But to put into perspective, I would love to buy 10, or even more, of these things to install in every cabinet I have. You say you would offer a volume discount, but is it enough to be enticing to your audience?
 
I just looked through your manual... you only have 1 VGA cable connected for the Jamma Video sources image... Does the RGB passthrough work for this usage as well? or does it only convert to VGA to safe levels and I need to split the signal before it reaches the board?
 
This might be useful for my Sega Driving cab conversion and getting an clean way to stream from it.

count me in for 1 (USA).
 
Unessential said:
I just looked through your manual... you only have 1 VGA cable connected for the Jamma Video sources image... Does the RGB passthrough work for this usage as well? or does it only convert to VGA to safe levels and I need to split the signal before it reaches the board?
Click to expand...
The inputs/passthroughs are all hardwired together on the board and offer no conversion whatsoever. They're basically there for convenience. In VGA splitting applications its a lot nicer to be able to just plug the existing VGA cable into one port, and plug a second one into the other port to go to the original monitor. The RGBHV wires connect to the same inputs as the VGA input and passthrough. In theory, if you were to attach to a JAMMA source and then plug a VGA cable into the passthrough you would get JAMMA level RGBS video on it but that's pretty useless unless you were trying to send it to an arcade-compatible monitor that could take such levels.

If you're asking whether you could use the input/passthrough for JAMMA to wire to the original monitor, then yes. Any signal going to any of the inputs will be unmodified, and available in its identical form on the passthrough. I only show one set of wires in the JAMMA situation because for the JAMMA games I own where I've installed one of these, I've used T-taps to wire into the JAMMA signals and as such don't need a passthrough since I'm just tapping the wires.

andynumbers said:
Hmm... how did I miss this?

I've been looking for a solution like this in to install in all of my cabinets for awhile now. Right now I have been manually wiring in Tim Worthington's AV driver PCB for a handful of my cabinets and it works decently...but it's a pain to install since it's all manual wiring. He recently released a new device called the SUPATT (https://etim.net.au/shop/shop.php?crn=219&rn=579&action=show_detail) that looks to be a much cleaner solution. I was planning on biting the bullet and buying a bunch of his devices for installation in all of my cabinets, but I was hoping there might be a cheaper/better device. Yours looks like it would be the better, lower cost option, but then I saw your asking price...

Tim's device is $60 (and yeah I know he's in Australia so shipping prices...) and your device is $80. I think your device would be a lot more tempting if it was priced accordingly. Just saying. Of course you put in the work to engineer and build your device and you have the absolute right to set your own prices. But to put into perspective, I would love to buy 10, or even more, of these things to install in every cabinet I have. You say you would offer a volume discount, but is it enough to be enticing to your audience?
Click to expand...
I hear where you're coming from but it isn't really worth my while to drop the cost much further. Not only do I have to contend with PCB manufacturing and sourcing the parts, I'm also hand assembling them and have to factor in the R&D costs that I ate to create them. This is board revision 4 and I spent a decent amount of time testing and verifying and such. And then there's wiggle room for loss in the form of potential paypal chargebacks, lost packages and damaged goods that I would be replacing. I considered originally listing them for $75 a pop instead of $80 a pop because it had a better ring to it and looked like a nicer number, but given the lack of interest if I want to make this happen as a group order I might have to drop the price anyway. That said, I'm not sure what five bux will do for any sort of interest. If there was high demand for something like this I could definitely see getting volume discounts and having it manufactured for me and just handling distribution which would bring the cost down fairly significantly, but there's a lot of risk and up-front costs for that and it appears that there just isn't a market for a higher-end VGA splitter board since most people can get the el-cheapo active splitters off Amazon for $15bux shipped and don't notice a quality difference.

When you calculated the cost of that other board versus this one, were you factoring in that the $80 includes all paypal fees and shipping so its the final value? I couldn't see a shipping price on the site you linked but coming from Australia I would assume it probably adds 10-15bux on top of the 60, bringing it basically in line cost-wise. To be quite frank, if you're looking to do 10 of these and want a steep discount you might need to do it yourself like I did. I couldn't find a splitting solution that I could afford for the amount of cabs I have so I paid the cost in my own research and labor instead of in dollars. If you value your own time and labor at $0 and weren't interested in the flexibility of a passthrough, contrast and individual RGB adjustments or multiple sync buffering styles you could potentially bang out boards for 1/2 to 1/3 the cost. But while I enjoy this hobby and enjoy building PCBs and designing and laying out circuits, I'm not in it to give away all my spare time. That's reserved for all the software I publish for free ;P
 
DragonMinded said:
The inputs/passthroughs are all hardwired together on the board and offer no conversion whatsoever. They're basically there for convenience. In VGA splitting applications its a lot nicer to be able to just plug the existing VGA cable into one port, and plug a second one into the other port to go to the original monitor. The RGBHV wires connect to the same inputs as the VGA input and passthrough. In theory, if you were to attach to a JAMMA source and then plug a VGA cable into the passthrough you would get JAMMA level RGBS video on it but that's pretty useless unless you were trying to send it to an arcade-compatible monitor that could take such levels.

If you're asking whether you could use the input/passthrough for JAMMA to wire to the original monitor, then yes. Any signal going to any of the inputs will be unmodified, and available in its identical form on the passthrough. I only show one set of wires in the JAMMA situation because for the JAMMA games I own where I've installed one of these, I've used T-taps to wire into the JAMMA signals and as such don't need a passthrough since I'm just tapping the wires.
Click to expand...
Hmm Doesn't that cause the video to dim? That's the issue with a lot of splitters, and turning up the video levels ot compensate is not always an option or not a convenient option... Or is the dimming caused by a lot of splitters caused by something else. That's my main worry, otherwise i'd grab one of these. Even if I don't end up using it, I got a friend that I know would make good use of it too...
 
In theory any sort of tapping of the input signals in a passive manner will cause it to dim. The trick is to sample the values without driving anything. Essentially, if you do not directly couple the input to the amplifier chip which drives the output then you are fine. I calculated the maximum theoretical drop in signal from my boards and worst case comes in at just over half a percent. So, you would lose a half a single percent of your brightness. This is the same principle that the Splitfire uses, for instance. The alternative would be to terminate the input, amplify it for the output as well as the passthrough, and then pass the separately amplified passthrough back to the original monitor. If you did this, then you need to get the termination on the input right (many arcade boards assume a 1-2k termination, not 75ohm) and there is a large chance that you blow out the highs (this is, for instance, exactly what happens on the official active splitter board that comes installed in some NNC cabinets for head-to-head setups) making the top part of the gradient identical no matter what you set your contrast to. Any time you reamplify a signal you have to deal with crushing the highs, terminating correctly, etc. So with this board the only time signal is processed is for the output, which is terminated at 75ohms assuming you will want to drive a VGA monitor or a capture card which assumes 75Ohm. The contrast knob is for the output signal only as well, and allows you to bring down an over-bright signal to acceptable VGA range so you don't get blown out/washed out colors.
 
At this point I am withdrawing these and all other boards from the market. I no longer sell these, my repro Monkey Ball or the repro NNC boards.
 
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