Supergun PCB - Laptop Brick PSU, Video Encoder, Kick harness port

[becker]

Howdy Folks!

This is my first post. I have been interested in making and selling Superguns a few years now.
My first and only supergun was in a shoebox. That was all I had a budget for at the time. The wiring and arcade power supply were inside the shoebox and was an accident waiting to happen.
I started taking jobs that I thought would lead to me learning how to make a nice supergun and get access to equipment. Now I have been doing PCB layouts full time for a over a year. I work at a place with an SMT line. I think it is time to revisit the idea of making a pcb supergun.

The pcb supergun is not a new idea. However, I haven't seen one that I would purchase. There is always something missing. I have seen some nice ones from the Euro guys; but they have SCART connectors and no video encoders for NTSC folks.
Video encoders for arcades are not a new idea either. Neobitz and JROK have been around for years. But, I haven't seen one put on a supergun pcb to make an all-in-one unit.
The pcb superguns I have seen also don't want to deal with the power supply. You will either have an arcade PSU which is scary because of the AC terminals exposed. Or they have a ATX power supply on the carpet with fans spinning.

Here is my vision for my supergun pcb -
1) No harnesses. I do not want wire harnesses. They are expensive and time consuming to construct. I want a JAMMA connect on the pcb that connects directly to the game board.
2) Power is supplied by a laptop brick. The 3.5mm barrel seems somewhat standard. I want between 12 to 24V. The pcb will have regulators onboard; 5V 3A regulator and a 12V 1A regulator. Feedback welcome. Information like is 65W enough? What is a common size connector so the power bricks would be easiest to source. I am trying to make things easier for the user by having a laptop brick but I need to know what is easy to get a hold of that works.
3) Video encoded on the pcb so there doesn't need to be a separate encoder. The encoders I have been looking at are the AD725 which I believe is on JROK. I also considered the ADV7604 which might be more complicated to implement. I would be getting the pcbs from an actual fab house so I am fine with fine pitch leads. My concern is compatibility and programming. Feedback from the community is welcome.
4) ESD protection. I am not sure if game boards have ESD protection or if it is even a concern. Based on the community feedback it can be added or left out.
5) I would like the pcb to have multiple boards butt-soldered or screwed together so it can create its own enclosure out of FR4 if possible. Its just an idea instead of cutting acrylic.
6) DB15 controller ports so Neo-Geo sticks work. Also I need a kick harness input to connect to extra buttons like CPSII.
Using a video encoder has me worried since it adds lag. I am not an electrical engineer or a programmer. I just design pcb layouts. Any advise on encoders is welcome. I have had a heck of a time finding ones that look like they would work for RGB at 15KHz.
I also have not come up with a good way to deal with the amplified sound. I read conflicting information about how complicated a circuit needs to be to send arcade board sound to a TV without blowing speakers.

Feedback is welcome. I am trying to sell the pcbs to you guys so let me know what you look for in a supergun. I feel like the pcb supergun would be the most wallet friendly way to play arcades at home.

 

[SmokeMonster]

HAS offers almost all of this already and is extremely affordable. I don't think that serious users would want a built-in budget encoder, nor would they want to rely on laptop power supplies for any power hungry boards like like CPS2 kit setups.

Here are a few issues that I notice right away with your plan:
- Chinese laptop PSUs are never as powerful as stated, and those that I've tried all introduced video noise, even the famous SC200 which is considered to be at the top of the line for laptop/switching type PSUs.
- If you went with a barrel plug, how would you safely feed both 5V and 12V?
- If you go with a laptop PSU, all -5V boards will be unplayable.
- Budget video encoders are sub-optimal, and pure RGB is going to be preferred by most people.

Basically, by the time you've added the correct power inputs, ditched a bundled PSU, and switched to proper RGB output (with optional audio attenuation, etc), you have just built your own HAS. The HAS is going to have an edge with most buyers though because of the myriad of other features it has (programmable auto-fire, lots of sync options, etc, etc). Also, the fact that you've never built a supergun yourself will probably lead to issues that you have overlooked.

 

[becker]

HAS offers almost all of this already and is extremely affordable. I don't think that serious users would want a built-in budget encoder, nor would they want to rely on laptop power supplies for any power hungry boards like like CPS2 kit setups.

Here are a few issues that I notice right away with your plan:
- Chinese laptop PSUs are never as powerful as stated, and those that I've tried all introduced video noise, even the famous SC200 which is considered to be at the top of the line for laptop/switching type PSUs.
- If you went with a barrel plug, how would you safely feed both 5V and 12V?
- If you go with a laptop PSU, all -5V boards will be unplayable.
- Budget video encoders are sub-optimal, and pure RGB is going to be preferred by most people.

Basically, by the time you've added the correct power inputs, ditched a bundled PSU, and switched to proper RGB output (with optional audio attenuation, etc), you have just built your own HAS. The HAS is going to have an edge with most buyers though because of the myriad of other features it has (programmable auto-fire, lots of sync options, etc, etc). Also, the fact that you've never built a supergun yourself will probably lead to issues that you have overlooked.

Thank you for the quick and detailed response, SmokeMonster. I will address your assumptions and concerns.

I came to the forums to try out ideas before spending time and money making them happen. I have been curious why superguns have remained more modular instead of more integrated. I personally do not like having exposed power supplies and separate video encoders. It makes for a jungle of wires which look good for a console experience I want in my living room.

I agree HAS is a wonderful product. I read the whole thread before making my first post. I am not trying to compete with the HAS. For people that have SCART or native RGB, the HAS is wonderful. I am taking a different path with my supergun pcb that is unexplored, kinda. All the pieces exist but have not been put into one unit.

I have made a supergun before using the normal jamma wire looms. I briefly mentioned it in the first post. It took up a lot of room and a lot of time. My experience making a wired supergun is my inspiration to not do it again. Which is why I want to go the pcb route. I am not a total noob at this stuff. I have been reading about arcades for several years. I have also made many pcbs and do it every day or work. Hopefully that calms fears of me being too amateur.

For power supplies I am going for a brick because it is enclosed and widely available. The idea is to use a 19V 65W brick into the supergun with a barrel plug. On the supergun pcb there will be regulators that convert the 19V down to 12V and 5V. I can do a third regulator for -5V for the Midway boards. The ATX plug from a PC PSU does not have -5V so people normally do not have sound on boards that need it. The alternative is an arcade PSU which are not safe to be outside a cabinet.

My need for a video encoder is to make the supergun usable by a much wider audience. Old Sony TVs, arcade monitors, and Fraimiester are great for people that can afford and find them. Native RGB is the ideal but it is out of reach for a lot of people. I personally can not justify spending the significant amount of money required to display native RGB. (I live in the USA). The video encoder is a compromise so more people can use it. I will put pass-through connectors on the supergun for people that can use straight RGB. The encoder I had in mind would be like having a JROK built onto the board.

My vision for a supergun is to have an all-in-one box. Down the road I also want to make joysticks so I can sell a "console" and controllers together. Step one is to see if there is interest for such product.

 

[jassin000]

The encoder I had in mind would be like having a JROK built onto the board

Then only people with 15khz complaint component/s-video devices will benefit from this device.
That's a handful of LCD's/Plasma's, but mostly just old tube (Sony) TV's.

I think today, if you wanted to do something really unique, from a all-in-one perspective...
You would include a scaler/31khz solution (like the new OSSC design) on board.

Think about it for a moment, a single board Supergun with a single HDMI output!
More people have a HDMI complaint display (over 15khz) in the modern home, its just a fact.

If we are dreaming big, might as well include a USB decoder for Xbox360/PS3 joystick support too.

Yup, 4 USB ports (players1/2/3/4) one HDMI output and a JAMMA edge.

 

[becker]

The encoder I had in mind would be like having a JROK built onto the board

Then only people with 15khz complaint component/s-video devices will benefit from this device.That's a handful of LCD's/Plasma's, but mostly just old tube (Sony) TV's.

I think today, if you wanted to do something really unique, from a all-in-one perspective...
You would include a scaler/31khz solution (like the new OSSC design) on board.

Think about it for a moment, a single board Supergun with a single HDMI output!
More people have a HDMI complaint display (over 15khz) in the modern home, its just a fact.

If we are dreaming big, might as well include a USB decoder for Xbox360/PS3 joystick support too.

Yup, 4 USB ports (players1/2/3/4) one HDMI output and a JAMMA edge.

HDMI would be really cool. I actually looked into HDMI first because, like you said, everyone has it. It was more complicated than I expected and I was discouraged. I recall it needing multiple chips because I couldn't find one that could start with RGB at 15Khz. So it would need to be converted twice. I thought by that point the frames of lag would be unplayable. At my work, I mostly deal with embedded systems that do not have displays. I have not dealt with video encoders or HDMI before. I was playing it safe with the AD725 because it didn't need programming and I knew it had been used for arcade video in other projects.
USB and wireless controllers are also really cool. I shy away from them because of my lack of programming knowledge. Maybe its not too difficult if I use a Cypress PSOC4BLE.

I feel like I am going after an in-between subsection of arcade lovers that may or may-not exist. The enthusiast already have proper arcade cabinets and monitors; so they would not want this supergun. The people I intended to make the supergun for might own 1 or 2 games and just bring them out for special occasions. Like its Friday night pizza with friends so bust out Street Fighter II to play tournaments. These guys would use a supergun for convenience and ease of storage.
However, I wonder if this subsection of players even exists. With all the effort it takes to play real arcade hardware on modern TVs; people probably just skip the trouble and plug a PC with MAME into the TV. Then they have HDMI and wireless controllers that already work.
Thank you for reminding me about OSSC. I had forgotten about that project.

 

[emphatic]

If I were to design an all-in-one supergun, I would make:

1. A flat, low profile PCB design in a size that will fit in readily available project boxes with optional acrylic enclosure sold separately
2. Onboard, switchable 110/230 power supply with a standard PC power cord connector supplying +5v, +12v and -5v straight to the PCB without any extra wiring. The voltage is of course adjustable with potentiometer just like in #3 below
3. Has connectors for inputs and outputs in a modular fashion on the edge of the PCB - customer can choose between having the ports on the PCB or connect them with wires for nice mounting in an enclosure of choice (you sell the connector types too as accessories, like RGB D-SUB or RGB Scart) just plug the connector you want onto the board
4. Input wiring with popular controller sold separately, NEO-GEO style ports ships with the supergun as standard
5. Have a nice scaler in stock for customers who doesn't already own one (OSCC is a great choice)