Video TX/RX fiddling

I think I've got just about everything needed for putting together the video Tx/Rx.  I've got both 1280 and 5.8 and will give them both a try.

I'll try all the various combinations of hooking things up, including direct connections from the cameras to the screen.  I imagine there will be much connectoring involved.

The diagram has all 8 possible connections among all the components.  I'll update as I get each one going.