Jamma Video Signal Splitter, Interest? - Now Available!

WIP Rev 2

Hello All,

Been working on REV 2 of the A/V Splitter. Notice I call it AV Splitter because I also believe I have audio figured out.

I worked with some very experienced friends of mine that work mostly with RF. The ghosting we saw on the old design in some cases was because of improper impedance matching causing signal reflections. The new design terminates the video signal at the board and makes two copies vs a passthrough and a copy. This is the only way to properly terminate the signal and get a clean signal on the board. Each opamp input has a series resistor from the video signal so that reflections are immediately impeded causing less noise between the opamps and the overall signal. I am expecting this design to be much better.

Audio:
The plan is to have audio work on games that use a Differential Single Ended amplifying circuits with should be most if not all games. Unless the game creates its own negative supply which is unlikely. Some games, like x-men, have sound on a external header, this will not support that. Only the mono jamma speaker audio signal.
I was happy to get input on this as well and am quite pleased with the theoretical design.

Right now the schematics is finalized and I am finishing layout. I hope to have some boards to test soon, end of September / start of October and i'll update you of results.
 

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Hello All,

Been working on REV 2 of the A/V Splitter. Notice I call it AV Splitter because I also believe I have audio figured out.

I worked with some very experienced friends of mine that work mostly with RF. The ghosting we saw on the old design in some cases was because of improper impedance matching causing signal reflections. The new design terminates the video signal at the board and makes two copies vs a passthrough and a copy. This is the only way to properly terminate the signal and get a clean signal on the board. Each opamp input has a series resistor from the video signal so that reflections are immediately impeded causing less noise between the opamps and the overall signal. I am expecting this design to be much better.

Audio:
The plan is to have audio work on games that use a Differential Single Ended amplifying circuits with should be most if not all games. Unless the game creates its own negative supply which is unlikely. Some games, like x-men, have sound on a external header, this will not support that. Only the mono jamma speaker audio signal.
I was happy to get input on this as well and am quite pleased with the theoretical design.

Right now the schematics is finalized and I am finishing layout. I hope to have some boards to test soon, end of September / start of October and i'll update you of results.

This sounds like a great improvement on both fronts. Looking forward to rev2!
 
Soon!

I worked for a few hours on this last night. I am really happy with the layout so far. If there a no issues with the design/pcb I think I can ship starting november.

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Looking forward to seeing this up for sale. I take my machines to conventions and usually put the Naomi's on projectors. It'll be nice to put other machines up too!
 
Bumping this old thread to see if this was ever finished or plans to finish it?
 
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