Powering your flight controller is an important aspect when it comes to building your own drone, if you get this wrong you might experience some release sparky the blue smoke monster.. Or worse you could end up having a power failure mid flight, damaging more than just your flight controller. In this guide I will discuss some things to think about when it comes to powering your flight controller.
This is a companion discussion topic for the original entry at http://blog.dronetrest.com/tips-for-powering-your-flight-controller/
I was using a 5v hobbywing ubec- just the positive lead connected in place of the esc supply. All was working fine. I tried switching to a diatone 5v micro bec same setup. My servos went insane (fixed wing fc with inav).
I’m wondering if the ubec ground needs to be connected…the 1st case no gnd wire and functions, 2nd case no gnd goes berserk.
Now I have a migraine over my head never great at electrical theory
I often feel the same 
Usualy when connecting various parts to the same circuit they all need to be connected to a common ground.