FPV Model and Boris B. have developed the Betaflight F3 flight controller in collaboration with each other. The unique feature associated with the Betaflight F3 electronic printed circuit board is that it has been designed to utilize all of the functionalities associated with Betaflight.
Let’s get going then!
Table of Contents
Features
This is a spectacular board for mini quadcopters. Micro quadcopters that support 30 x 30 mountings, would love to have it on board.
- Built-in Power Distribution Board and 5V BEC
- Built-in On-Screen Display support
- A built-in current sensor that can handle up to 100A continuous and 160A burst
- SD Card slot for Blackbox recording
- 3 UARTs
- Boot button for easy firmware flashing/recovery
- Neat wiring
- USB port facing a convenient direction
- SBUS support (no PWM)
- Weight: 8.6 grams
Board Design
The original packaging of the board consists of a plastic box while the board is wrapped around in white foam. The bundle includes a servo cable that can be used for the receiver.
The board gives a solid feel and both sides of the board have to be utilized during the build. One side of the board contains pads for running ESC wires while the other side has pads for the ESC signals and holes for other components.
The main battery power wires go on the top and bottom which is a peculiar design choice. The positive wire gets soldered to the bottom and the negative wire gets soldered to the top.
Since the ESC power pads are located at the bottom of the board, so soldering can get a little tricky.
Soldering ESC Wires to Betaflight F3 Board
This can be accomplished in a couple of ways:
- Get the wires from the ESCs desoldered and have them soldered to the BetaFlight F3 flight controller at full length. Mount the board in the right direction by flipping it around and place the ESCs on the arms. In the end, trim and solder the wires to the respective ESCs.
- You can attach the BetaFlight F3 flight controller right side up and place the ESCs on the arms. Then, run the wires to where the pads are supposed to be on the underside and trim them according to the desired length. Finally, flip the board and solder. This technique is suitable for a symmetrical frame. For a non-symmetrical frame, orientations will have to be tinkered with.
To be honest, the first method is way easier.
As soon as you get the power wires soldered, the signal wires are a piece of cake. The pads are located at the edge of the board. So, by placing the board in the right orientation, simply trim the signal wires and ground wires to length and solder away.
Soldering the Board
You can view the schematic of the flight controller from the top. The solder pads at the top side are not labeled. The pads are labeled at the bottom so it becomes important for you to consult an external schematic such as this one before you actually start soldering.
Here is a bottom view schematic of the Betaflight F3 flight controller.
As can be seen, there is a little amount of soldering required here before the board can be flipped around to mount properly.
The first row of solder pads is AGND, RAM, VOUT, and VIN.
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- AGND is filtered ground which is used for the video transmitter ground. It will ensure that the video feed is clean and does not get disturbed by spikes in voltages
- RAM is positive. You can solder the jumper to either RAM 5V or RAM VBAT for raw battery power.
- VOUT is the video out to the video transmitter
- VIN is the video on the board from the camera
Most of the modern-day transmitters and FPV cameras take 2S to 6S and do not generally work with simple 5V. So, you will be required to solder the jumper to RAM/VBAT. The Runcam split only takes 5V so ensure that you jumper the pads to 5V.
GND, 5V, Soft_RX, and TX are in the next row. Soft_RX and TX is SoftSerial which is a telemetry protocol that can be used in the BetaFlight F3 flight controller if the receiver is compatible with it. FrSky receivers of the old days such as the D4R-II came with SoftSerial support but the latest SmartPort telemetry on the X4R and XSR is better.
GND, 5V, RX2 and TX2 form the next row. This is UART2 and can be used to connect any external peripheral devices such as Bluetooth or GPS.
GND, 5V, and LED are low underneath. It can be used to set up LEDs and lets the user configure the colors using Betaflight.
PPM receiver is in the next row. However, serial receivers are faster and more affordable as compared with the PPM receivers.
The last row is for connecting the serial receiver. We have GND, 5V/3V, and SBUS/DSM. This is where Spektrum and FrSky SBUS receivers will be hooked in.
If you own Spektrum receivers, the jumper will have to be soldered to 3V. Anything other than this will have to be soldered to 5V.
The jumper must be soldered for the receiver to get power. The receiver will not work if the jumper is left unsoldered.
Soldering the FPV Components Can be Cumbersome
A camera and a video transmitter form your FPV gear. Both need power while there is only pad on the whole segment of solder pads that outputs raw battery voltage.
So, we have limited options:
- If the output power of your video transmitter is 12V, then the transmitter power leads can be soldered to the board and the camera can be powered from the transmitter. It goes without saying that the VOUT and VIN need to be connected to the transmitter and camera respectively.
- If the transmitter does not output power, then the red positive wire from the camera and video transmitter are soldered to the same solder pad and the same or two different ground pads are used.
- If you are using Runcam Split or any other camera that uses 5V, there is only one 5V regulated port that can be used to power the camera. So, if your transmitter only takes 2S to 6S, then it will have to be powered from one of the ESC leads.
- If your transmitter only takes 12V and you are building a 4S or higher setup, a 12V step-down regulator will have to be connected from either the battery pads or the ESC pads and the transmitter will be powered from there.
Betaflight OSD Support
Since the board offers support for the Betaflight OSD, you can view important data such as battery voltage, current consumed, current draw, flight time and PID values. You can also tune the PIDs from the OSD menu, vary rates, PIDs, rate filters and values on filters.
Conclusion
The OSD compatibility and clean and low profile build render this board an excellent choice for your quadcopter. The board boasts a great build quality. Having said that, it is rather difficult to solder the board and soldering becomes easier on another OSD enabled board such as the Omnibus F4. The Omnibus F4 does not come with an integrated PDB.
I have used the Betaflight F3 Flight Controller in a couple of my quadcopters. In one of them, the video could not be transmitted from the quadcopter if the video terminals were hooked up to the board. If they were connected together, the video would get transmitted. I scoured the internet and found other users who had similar issues. FPVModel asked me to send it back to them and offer 50% discount on my next purchase.
If you prefer a tight and neat build, this board is the one for you. Having said that, there is still plenty of room for improvements. Once the board has been connected, it will have to be configured via the Betaflight Configurator.
