If you like to keep up with the Jones’ you’ll know that F4 flight controllers are where it’s at and there’s simply no better option than the BrainFPV RE1. It’s got an awesome spec sheet and stats, all of which can be found on their website www.brainfpv.com
To keep to brief, here are the features we’re most interested in:
- STM32F4 180MHz processor
- Shiny Bosch Gyro (secret sauce)
- Twin programmable iLaps transponder LEDs
- Custom vector based OSD
- Stackable with dedicated PDB
- Current and Voltage sensors
- Smartaudio VTX support
For this build we’re using an arm set for the X210 that’s currently in development. Our pilots have been testing these 7mm thick beasts on the track and so far they’ve taken everything we’ve thrown at them. Look out for the new X210 arm sets available soon.
Our build kit:
- X210 frame kit, 30mm standoffs, 3mm Micro plate
- 7mm Atto Duo arms
- BrainFPV RE1 F4 FC
- BrainFPV mBPV2 PDB
- Gemfan Maverick 24A 32Bit ESCS
- Gemfan 2205 2450kv motors
- Runcam Swift mini camera
- Machine ET25R 25mw VTX w dipole whip
- Spektrum satellite receiver
- Gemfan Flash 5152 props
Build weight 320g
We’ll also need:
- A temperature controlled soldering iron
- Fine solder (1 or 2mm)
- Small cable ties
- Heat shrink of various widths
- Helping hands or similar clamp (useful)
- Circuit/continuity tester
Prepping the RE1
Before you start assembling your new quad, there’s a couple of steps to take to prepare your RE1 flight controller. First is to plug it in and flash betaflight. The board has it’s own boot loader and custom .hex file. The .hex file can be found here. Once you have that, bridge the boot pins on the back of the FC and plug in into your PC. Flash betaflight as normal using the file you downloaded from the BrainFPV Github. DO NOT CLICK FULL CHIP ERASE as this will mean some reprogramming must be done. There’s full details of what to do on the BrainFPV site under support should you need it but I say again. DO NOT CLICK FULL CHIP ERASE and you’ll be fine.
The second thing to so is to choose your receiver pin voltage. On the underneath of the FC are two sets of pads you can bridge. One for 5V and one for 3.3V. If you use a satellite receiver like in this build you must bridge the 3.3V with a blob of solder. Do this now or you’ll have battery voltage over your receiver pins.
Now to install the pins that will plug the FC into the PDB. Using the nylon standoffs as a guide, keep the included pins in place with the silver contacts on the board and the gold contacts together. Once held in place, secure the pins with solder making two sets of plugs to connect the two boards.
Next connect your IR LED’s to the board. Cut the legs of the LED’s to size and solder direct to each side of the board with the LED’s facing outwards. The flat side of the LED indicates the negative pin and should be on the bottom side of the board.
Prepping motors and ESC’s
With the board ready to go on the frame, tape your ESC’s into place to measure your motor wires. We’re using Gemfan Maverick’s which come as a bare board which makes a very clean build. Once you’ve soldered your power and signal wires, leave them long for now and measure, cut and trim your motor wires. Solder them to your ESC’s and heat shrink the whole lot for protection. Repeat for the other corners.
With the ESC’s now fully wrapped tape them to the arms and install the mPBV2 in place. Solder the main battery leads then trim and solder your individual ESC leads to the pads on the PDB. Be aware, the mPBV2 is a serious bit of kit. it uses heavy duty copper and soaks up heat. Use a hot iron with a large surface are to try and get the job done quickly without overheating the other components.
The last connection on the PDB is for your FPV power. The mPBV2 provides LC filtered full voltage, 10v and 5v options. We’re using the ‘F’ or ‘filtered’ pin for the VTX power and the 10V for camera power. The video connection on each will go through the OSD pins on the RE1. It’s great having so many options with a filtered power supply. Adding chunky LC filters or capacitors is awkward and having a clean FPV power supply built in is a real bonus. Well done BrainFPV.
Once that’s done, carefully push your FC into place connecting the pins you soldered earlier. With the FC in place, connect your VTX video to video out and camera video to video in.
Next solder the ESC signal cables to input 1, 2, 3 and 4 and your chosen receiver (in our case a de-cased spectrum satellite) onto the receiver pins.
Barometer – Optional
You don’t need the RE-1 Baro add on to run betaflight. It enables the FC to use air pressure to measure altitude. We put it on this build because we had one. It’s interesting to see just how far up you can legally fly in the UK. It’s a lot higher than we think.
To fit it, just place the open cell foam in the right spot (check BrainFPV support) and click the Barometer into place. In our build it doubles as a handy shelf for the RX and looks pretty sweet too.
This may seem like a short build log because it is. Building with this FC is incredibly easy and compact. There’s loads of room for a swift mini even with short standoffs and the 7mm build looks killer. Once the camera is fitted the receiver and VTX fit in nicely and are secured with adhesive foam.