Questions about building a CMVS

[famitek]

Hi everyone, I'm a Neo Geo n00b who has been lurking on the forums for a while, and I think I am ready to bite the bullet and build a CMVS. After reading many forum posts and checking out Xian Xi's fantastic tutorials, a few questions remain that I'm hoping you can help me with.

I picked up a MV-1FS board, so I think I will forgo wiring joystick ports, and I have that nice headphone output I can take advantage of too.

Anyway, here are the questions:

1) Can the board be run without +12V? My understanding is that the 12V is only used for audio amplification, and that the board and headphone connector should still work without it. I would like to use the same power supply that I got for my AES (5V) if possible.

2) Is there a connector available that I can use on the 4-pin headphone connector? I would like to keep the board "stock" in case I disconnect it at a later date.

3) I came across plans for an RGB to NTSC video adapter in Ben Heck's consolization guide ( http://www.engadget.com/2006/11/28/how-to-consolize-an-arcade-game/ ). This looks to be the cheapest option, but is the video quality OK? Or is it worth spending more for a JROK or Neobitz? Are there better DIY options?

4) Are the built-in ports wired for coin insert and start? Or only start?

Thanks in advance for your help.

 

[systmdfect]

I had XX build mine for me. About the headphone and coin insert though; why would you want to keep it stock. I mean it's not an AES, and consolizing it, if done properly, still allows it to be used in a cab. It would also raise the value of the system. You will probably want a unibios to add on as well. You can just use the select button to insert coins, Or close dip 7 for free play.

 

[Xian Xi]

Hi everyone, I'm a Neo Geo n00b who has been lurking on the forums for a while, and I think I am ready to bite the bullet and build a CMVS. After reading many forum posts and checking out Xian Xi's fantastic tutorials, a few questions remain that I'm hoping you can help me with.

I picked up a MV-1FS board, so I think I will forgo wiring joystick ports, and I have that nice headphone output I can take advantage of too.

Anyway, here are the questions:

1) Can the board be run without +12V? My understanding is that the 12V is only used for audio amplification, and that the board and headphone connector should still work without it. I would like to use the same power supply that I got for my AES (5V) if possible.

2) Is there a connector available that I can use on the 4-pin headphone connector? I would like to keep the board "stock" in case I disconnect it at a later date.

3) I came across plans for an RGB to NTSC video adapter in Ben Heck's consolization guide ( http://www.engadget.com/2006/11/28/how-to-consolize-an-arcade-game/ ). This looks to be the cheapest option, but is the video quality OK? Or is it worth spending more for a JROK or Neobitz? Are there better DIY options?

4) Are the built-in ports wired for coin insert and start? Or only start?

Thanks in advance for your help.

I'm guessing this is James?

The MV1FS has audio even without the 12v hooked up so there is no hack needed to get audio. Just simply tap 3 points (Ground,Audio Left and Audio Right) from the headphone jack. The Headphone jack is labeled 1-4 for the pins. Pin 1 is Left, 2 & 3 are ground and 4 is Right. You can solder to the under side of the board to hide the wires.

For the video encoder you have several options ranging from building your own or spending about $30-100 on a prebuilt one.

If you only plan to have S-video and Composite I would recommend getting the Neobitz-S DIY kit, very affordable. Of course if you know how to build circuits you can get the encoder chip free as a sample from the company that makes them and then you just need to follow the schematic to build the circuit yourself.

If you want VGA some people get a Wei-Ya RGBS>VGA encoder which I think is around $80 or so.

 

[famitek]

Thanks for the quick replies! I found out that the headphone pins can be connected with a Molex 70066 connector (Digikey part WM2802-ND), similar to the PC speaker or other connectors on a PC motherboard. And I am definitely planning on getting unibios for both my AES and MVS.

 

[Xian Xi]

If you plan to have audio jacks on your CMVS the molex would be pointless to have.

 

[famitek]

If you plan to have audio jacks on your CMVS the molex would be pointless to have.

I'm not sure what you mean... If I use a jamma harness for the power and rgb and use a molex for the audio, then I wouldn't have to do any soldering on the MVS board itself, right?

 

[Xian Xi]

Are you making a CMVS or a supergun?

 

[famitek]

Right now, I'm planning on making a CMVS. If that goes well, I will probably try my hand at making a supergun at some point in the future.

 

[Xian Xi]

If you are making a CMVS with an MV1FS you wont be using a jamma connector or harness on the board. You solder to the points on the bottom of the board.

When I get my MV1FS in I'll finish the guide.

 

[Bskull]

I look forward to seeing that guide as the others have been quite fascinating. I apologize in advance if this post is way off-topic.

 

[Bay78]

I'm still trying to figure out how to turn my MV-1F into a consolized board but still able to plug into jamma

 

[duo_r]

ok if I have the Atlonga RGB to YUV box which MVS do I want to buy? It needs RGB and Composite video to properly work and will transcode to Component video.

 

[Xian Xi]

ok if I have the Atlonga RGB to YUV box which MVS do I want to buy? It needs RGB and Composite video to properly work and will transcode to Component video.

If you need RGB and Composite Video then you need an RGB to NTSC encoder like the Neobitz and JROK. I'm pretty sure it just needs the sync from the composite video so you don't need an extra encoder.

 

[Xian Xi]

I'm still trying to figure out how to turn my MV-1F into a consolized board but still able to plug into jamma

The MV-1F and FS are basically the same board except the FS is smaller length-wise and some other minor things but essentially the same board.

 

[famitek]

When I get my MV1FS in I'll finish the guide.

Great! I'll look forward to it.

 

[Drumjay]

I'm guessing this is James?

No, this is James! A coincidence that he's asking the same questions as i was through email

My CMVS is well under way now. Still looking forward to your guide. They're great!

 

[warmachine]

ok if I have the Atlonga RGB to YUV box which MVS do I want to buy? It needs RGB and Composite video to properly work and will transcode to Component video.

This should work for you.

http://www.gameland.gr/geoanas/realarcade.htm

 

[Drumjay]

Questions again! Sorry. Being in the UK can I tap RGB direct from the 8.5k resistors? Not needing an encoder. Would i then just take the ground for each off the jamma edge?

Got the sound sorted, thanks Xian.

All I need now is the power tap. Where is the best place?

Thanks in advance. I have checked all the available posts for this, but there doesn't seem to be any.

 

[Xian Xi]

Yes you can tap them from the resistors keep in mind you might need to use 82ohm resistors in line as the image may be too bright for your TV. The ground you can get from multiple points on the board, use a multimeter if you want to keep the edge clean. You can pretty much tap the +5v and ground anywhere on the board but you might want to use some place where it's bigger than a trace for it.

For the RGB resistors I have to check as I am not if it's the 8.5ks on the 1F as I remember the picture being weird.

 

[Drumjay]

Many thanks! Very helpful. I have some 1/4W –1/2W 82 ohm resistors, would they be sufficient? Would using in line pots also help the brightness problem? Would it be better way to solve the issue? Your help is very much appriciated!

 

[Xian Xi]

In line pots would be best so you can tune it to what you want. I would use 250ohm pots or at least 150ohm. But you can always go bigger if you feel 250ohm may not be enough.

 

[famitek]

Well, I have just finished testing my new CMVS (if it can even be called that yet). I would up soldering my own circuit board for the video using the AD725. Soldering to those surface mount pins just about killed me! And the stupid thing actually worked the first time around. So I've played a couple of rounds of Metal Slug 3 to celebrate. Thanks for you guys help. Next I'll be putting in the Unibios and figuring out how to put this all into a case.

 

[Xian Xi]

Just a heads up letting you guys know the tutorial is up for the MV1F/MV1FS. Link is on the main page.

 

[sackashiet]

Just a heads up letting you guys know the tutorial is up for the MV1F/MV1FS. Link is on the main page.

Nice guide in addition to your other great guides. makes me want to do a CMVS just for fun, but I already have a supergun... ah I'll just do it anyway!