Hi guys,first of all sorry for my english but it's not my first and either second languange . I'm new in the "fpv" and i'm trying to build my first quad altough i'm having some trouble concerning the flight controller/rx/pdb connections.The main issue is that i don't know how i could power the x racer f3 through the matek pdb.The receiver as you can see is powered by the 5v bec from the pdb(I'm following the diagram that i've found in the matek pdb).Moreover i'm wondering if someone know what voltage can handle this F.C. Hope someone will help me because i can't wait to fly this little beast.  Peace.

I just did a build with an X-Racer F303 and Matex PDB as well. I did the following:

Matek PDB's 5V BEC output => any unused F303 ESC output (+ and - pins only)
F303 Sbus output => FrSky X4R

Because the ESCs on a mini quad are normally "opto" (no BEC), you only connect signal and - of each ESC to the FC. You still have 4 more (so you can have an octocopter), so use one of the leftover ones to supply the FC with power. Unlike #1-#4, which use only signal and - pins, you will use only + and - pins for #5.

Now your FC is powered. When you connect it via PPM or Sbus to your Rx, you will use a 3-pin servo cable, which will supply power to the Rx.

If you don't want to switch the PDB=>Rx connection you already have, you can probably power the FC from the Rx instead. The voltage will simply flow the other way over your Sbus/PPM servo cable. However, your failsafe will be a little less safe because if your Rx loses power, your FC also will, so it cannot do any failsafe operations.

This is something that annoyed me when I started too: neither Rx or FC have any obvious "power in" connector! Hope that makes things more clear!

Yea Receiver should be powered from FC.. You can power the board with one of the spare motor pins... This FC can only take 5V

(24-Feb-2016, 05:16 PM)Oscar Wrote: Yea Receiver should be powered from FC.. You can power the board with one of the spare motor pins... This FC can only take 5V

Thank you both guys.I finally use one channel input to power the fc(through the rx) and yesterday this beast has her first fly and first crash,these motors are insane!!!!