I will start by confessing that I know next to nothing about R/C systems, so I am looking for validation from those who are better informed that what I think will work actually will work.
I am the designer of the cam-do controller board for GoPro cameras and am often asked about using the board in R/C planes, helicopters, robots, etc. [Actually, they usually ask if we can provide a long range transmitter for our remote control product, which seems redundant when they already have a working R/C system.]
While searching for data on what the R/C receiver outputs look like, I came across the Pololu RC Switch Pololu RC Switch with Digital Output, which appears to do exactly what my customers need.
If I have understood correctly, the Pololu switch will output the needed signal to trigger the cam-do board. The needed signal is 2.0 - 20 V - into a simple opto-isolator input. The signal needs to last at least 250 mSec. In other words, the same as lighting one LED.
Feeling overconfident, I have even written it up in the Application Notes for the controller board.
Please, if I have misunderstood something about R/C or the Pololu switch, tell me now, before I make a fool of myself.
Thank you, Pololu, for providing a simple, low-cost solution to this problem.