Betsu Betsu: Open source Arcade Audio/Video splitter for capture/streaming

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    • Betsu Betsu: Open source Arcade Audio/Video splitter for capture/streaming

      Betsu Betsu is an Open Source Audio+Video splitter, which can be hooked up to cabinets jamma harness to produce output suitable for Streaming/Capture through OSSC + a capture card.

      The schematic, board and gerbers are open source (Github here), so you are free to build it yourself, but I’m also planning to make some of these and sell them for about $70 + shipping if there's interest.

      The current prototype board looks like this. The final board will be pretty much the same, but with different trim-pots (cross slot) and a few minor adjustments. Soldering will also looks a bit nicer, since I'll probably do heat gun reflow instead of just hand soldering.


      High level features:
      • Power, video and audio input through terminal block. Easy to wire up to cabinet Jamma harness, or a jamma adapter.
      • “Standard” Mini DIN 8 video pinout, for hooking it up to OSSC.
      • Mono audio output through audio jack.
      • Adjustable RGB video levels.


      More detailed features:
      • Line level audio conversion with galvanic isolation (TY-250P).
      • Buffering and unbiasing of Video and Sync signals to safe levels (THS7374). Input is AC-coupled, output is DC-coupled. Safe to drive 75ohm loads / OSSC.
      • Audio completely isolated from video (no common ground) to avoid ground loop noise.
      • Very small footprint (65x40mm).
      • 2.5mm mounting holes
      • Power LED
      Schematic (v0.2): i.imgur.com/4mxQ95j.png
      Board: i.imgur.com/C43zLZX.png
      BOM: docs.google.com/spreadsheets/d…IHNT_xPA/edit?usp=sharing

      Sample captures:
      Both of these are Betsu Betsu into OSSC with 4x linedoubling, then captured with USB3HDCAP in OBS, and scaled to 1080p. Audio is wired from Betsu Betsu to PC Line in directly.


      Action shot of prototype board being used to capture Demon Front above.

      I was previously tracking this in this idea thread, as I was constructing it, but since this is pretty final now, and no longer just an idea, moving it here.

      Let me know if this seems interesting, and if there's any feedback!
    • Apologies for butchering the audio circuit. I think I will use this along-side a jamma extender to easily 'patch into' the rgbs lines from the jamma wires.

      Changed the audio to line-in and audio goes directly to 8 pin mini din output eg ossc or syncbooster or capture card.

      Fun and easy to build, I have 8 spares (all components shown) if anyone is interested in building their own or buying a pre made one. (I'm in the southern hemisphere)

      Thankyou @buffi !! , I'll let you know when it gets used in a public event.
      Images
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    • Awesome!
      Glad you like it :)

      I would however not recommend moving audio to mini din when using OSSC.

      I believe I have gotten weird ground loop noises when doing this since it will share GND with video.

      Imo its better to have it completely separated from the video circuit.

      The post was edited 1 time, last by buffi ().

    • hey @buffi ive been messing around in a video editing app so I will put a video on youtube of me playing various games on a shitty MAME based arcade board, using the betsu betsu as second output into OSSC -> datapath capture card. credits to you in the video too of course :)

      coming soon!

      youtube.com/watch?v=z6k8rclMwLM
      Images
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      The post was edited 2 times, last by evilsim ().

    • FYI there is a world record attempt happening at 1989 bar in Newtown in a few days and they will be using one of the BetsuBetsu's I've made to record the action from the cabinet to an OSSC.

      there will probably be a video made eventually by Ben, I'll link it if that happens.

      thanks again!

      p.s. ive made some more and using just a simple goldfinger along with a jamma socket instead of an extension cable (neater, smaller)


      EDIT: unfortunately the recording didnt happen with Betsu Betsu this time (they just did it oldfashioned way with a decent SLR camera on a tripod), but I am making some of these items and will be selling them soon. This is a really great device, the picture is just fantastic.

      The post was edited 1 time, last by evilsim ().

    • Dropshock wrote:

      Just stumbled across this project and had to make an account to express my interest. Very cool stuff, @buffi!
      Hey, glad people like it.

      Mostly built this so I could capture stuff I'm playing, but might as well make the design open.

      There's some more sample captures at my youtube (all pcb videos there)
      youtube.com/channel/UC1mA-MUD2n0FlYIYrH4PpRg
    • Experimenting a bit with something that just plugs into Jamma between the cab and the game (similar to Splitfire and devices like that).

      Also want to go back to doing AC coupled video outputs since I think I get cleaner signals with that after some more experimentation. This ups the components a bit, but probably worth it.
      Changed all caps to surface mounted to simplify routing.

      Tried to route something today, looks like this.
      I don't really know much about what I'm doing though since I'm more of a software than an EE guy, but I think this should work alright.

      Gonna clean it up a líttle bit, fix the silkscreen and then order some prototypes. Will be at least a few weeks until I have the boards, but think this could be a fun project.



      About 11cm x 8cm.
    • Cleaned up a bit.

      Ordered some prototype PCBs based on this.
      I'm sure I'll go through at least a few more revisions before I like what I have, but should be fun to have something to play around with.

      Edit: Please bash my routing. I don't really know what I'm doing.

      The post was edited 1 time, last by buffi ().

    • New

      The Jamma ones? No , i don't even have one for myself yet (need to locate parts + solder it up first).
      Not sure I'll be selling these at all, but I'll make the design open at some point, so others can do that if they want to.

      Need to get them working first though, so may be a while.

      The non-jamma ones, I think I might have a spare one assembled somewhere, but dunno how interested you are in that.

      edit: And yes, I know the spacing of the fingerboards (especially the "key" part) is shit. This is just a prototype revision :)