I'm not certain this is the correct place for this question but here goes..
After a crash and identified ESC fault All ESC have been replaced on the Octo.
The replacement ESC are Opto so the pixhawk is being powered purely by the pixhawk power module.
My RX is a futaba Sbus - It's plugged in the RC port.
When I connect USB everything powers up as expected including the RX and it works and calibrates however when I remove USB the RX power is lost - Everything else is fine.
Is there a software parameter to power the RX that needs to be turned on ?
Why is there no power to the RC in port when powered from the power module ?