Hi Jim, yes, i got it all set up and it works flawlessly. I am using a cheap second flight controller to switch recording on/off on my Runcam Hybrid, and to switch between 3 different power levels on my vtx via smart audio.
I am running iNav on the second flight controller, the f/c is just a Omnibus F4 Nano V6, but i would imagine any iNav suitable f/c with a smart audio input will work. I am simply splitting the sbus signal from my rx so that it goes to both my main flight controller, and the secondary f/c. Sbus being a one way signal means that both f/c’s are happy together on the same rx - they don’t know each other is there.
I followed the advice on one of Painless360’s video’s to set up my iNav f/c so that it let me switch my vtx power levels. I must give him a big shout out because i would never have worked it out for myself! It was a little bit more involved than say just setting the f/c up to operate your Runcam. Here is the video - hope it helps, some very good info. And if you wanted to go one step further and have iNav automatically switch vtx power levels, dependent on how far away your craft is from you, he shows how to do that in a following video. That is not something i have tried yet, i am more than happy just using a 3 position switch to do the job.
The only other thing i did was add a 3 way camera switcher to my onboard set up, that way i can switch to the iNav f/c’s osd if i need to - to be honest the only thing i set up on that osd was the vtx power setting level, just so that i could confirm it had switched when i commanded it. It always works, so i don’t use the switcher at all now, the vtx power levels switch every time.
But without the added camera switcher it is very simple to do - just one small extra f/c that weighs next to nothing, just run your vtx smart audio cable to it, along with your Runcam control tx/rx wires.
If i can be of further help, let me know, will do my best.