I am setting up an octa, having just replaced my APM with a pixhawk.
As the max current will be over 90A I have made up an attopilot 150A system and a 5V BEC, all wired into the power port. This is working fine.
The Receiver (taranis X8R) is plugged in the RC (s-bus in) port and is powered from this connector.
Contrary to this diagram, there is no continuity between the RC +5v and the other +5v pins in that rail but there is about 4.7V present on the RC middle pin. There is no voltage on the other +5v pins unless a ESC etc is plugged in.
Also (as documented) any 5v on the other (not RC) power pins will power the pixhawk, giving redundancy if the top power connector is also supplied. Any 5v (input) on the RC pin will NOT power the pixhawk.
Finally Im getting to the point.
I am running a small servo and other devices directly from the X8R receiver, therefore these are powered from the pixhawk. They are not drawing much current BUT they easily drag down the voltage to 3v or less.
I have plugged in another BEC to boost the RX supply but am not sure what effect this will have on the pixhawk RC pin output. I may remove the 5v wire from the S-Bus lead and just use a 5v bec for the RX (and also the pixhawk servo rail).
Any thoughts or info on the current rating of the pixhawk RC +5v output would be welcome.
Also I cant find any info on the small amber b/y led or the blue one.