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Small Jamma AV-splitting board for capturing video of cab

These 4 x resistor/capacitor arrays are real cute...
Should hopefully not be worse to solder than the TSSOP
0TX1aPs.jpg
 
Did some testing with new board. Works well, video looks awesome.

Audio has high frequency noise though which I _think_ v0.0 did not. I'm going to do some more testing to see what's up.

Did the testing with a real noisy PSU, so might be related to that? Will hook it up to my cab as well to see if it still happens.
 
Did some testing with new board. Works well, video looks awesome.

Audio has high frequency noise though which I _think_ v0.0 did not. I'm going to do some more testing to see what's up.

Did the testing with a real noisy PSU, so might be related to that? Will hook it up to my cab as well to see if it still happens.
Less noisy there, but I guess this means that I have a ground loop in my other setup... I´ve been using common ground for video and audio so far, which is maybe not a great idea.

I guess I need a new version which just uses the audio jack ground as ground for the transformer. Should probably have thought of that before, but oh well...

At least the video looks great! I can probably hack something together to verify that the high frequency noise goes away when not using a shared ground, but it will rely on an ugly hack with the transformer and audio connector off-board with wires...

Then its another 10 days or so waiting for the next revision pcb i suppose.
 
Did a ugly hack where I route the video to a separate board which has isolated audio ground. Removed the annoying noise I was having previously.

I think I'm pretty happy with the current configuration, so I'll change the design to work like this, and then this is more or less done.

Here's a capture I did today to try it out:
https://www.youtube.com/watch?v=uihHkYRbM4E

Image of what my hacky setup looks like now:
xZKL5Fa.jpg

Final board will look as pictured above:
Small Jamma AV-splitting board for capturing video of cab

BOM is about $20, including taxes, see below:
https://docs.google.com/spreadsheets/d/1b9EG2nF_7fvYWe0XPSzKwB71s6kuO3IKsdXIHNT_xPA/edit?usp=sharing
 
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