Want to learn how to build an FPV rig? This guide will walk you through your first FPV freestyle build. These parts were hand-picked to balance cost and maximize performance. The TBS Source One is a popular frame for it's low cost, high quality carbon fiber. It's easy to work with and provides more than enough space for your electronics. We've got a 32bit 4-in-1 ESC to bring you the smoothest flights and fewer solders as well as the popular TBS Unify video transmitter (VTX).

Tools

This build requires some soldering experience, but could also be a great way to practice. I highly recommend a flux pen, good 63/37 leaded solder and a quality soldering iron. Here are the tools and supplies you'll need. I've included direct links below in the part list.

Soldering iron

2.0mm hex driver

Industrial Tweezers

Wire cutter/stripper

Scissors

Heat gun or lighter

Ruler and cutting mat

Multimeter

Additional Supplies

A variety of heat shrink tube sizes

Blue Loctite

Zip ties (small)

63/37 leaded solder

Liquid soldering flux pen

Hardware

The frame kit and motors come with all the hardware you need, so you don't need to buy any additional hardware. I used blue countersunk washers and screws to add a little color, but those are entirely optional. What's great about a frame like this is you can embellish a little.

Frame Assembly

We're using the TBS Source One V3 which offers a couple new features over the V2, but most notably the arms mount below the base plate. This provides more space for the stack, but in our case we've got more than enough space. At least the battery strap won't rub against the components! The main thing to keep in mind is to orient the silver press nuts upward. Sandwich the arms with the small plate at the very bottom. Insert the screws upward and use the 4 tallest screws in the middle for the stack.

Motors



Mounting the motors is pretty straightforward. Use the "For 4mm arms" screws and some blue Loctite to ensure they won't vibrate loose. I used some 1/4" Para-Max to sleeve the motor wires, but you can also secure the wires to the arms with electrical tape. If you do want to take that route you'll want to use some 14mm shrink tube to cover the ends of the sleeving.

Before you start soldering you should remove the flight controller from the 4-in-1 ESC to make it a little easier. Now I rotated the ESC board so the motor wires solder to the side and the battery tab points toward the back. This isn't the intended orientation, but I prefer to have my motor pads accessible. Plus you can add a capacitor and it'll be protected inside the frame. You'll need to paste some commands later during the Betaflight configuration to address the orientation change, but it's very easy to do and the commands are available below.

Remove the nylon standoffs from the side you're soldering so you don't accidentally melt them. Flux and tin each motor pad ensuring each is completely coated with a bubble of solder. These are pretty long pads so you'll want to push the solder back so it looks more like a loaf than a ball. If you're right-handed start from the rightmost motor pad and solder all 6 wires from right to left. If you're left handed start from the left.

Cut each wire to length as you go, not all at once.

Take your time and press the wire into the solder slowly to avoid bridging the pads. If you used sleeving be sure to melt the shrink tube over the ends.

Power Connector



Now it's time to solder the power lead. Unfortunately this stack doesn't come with an XT60 or wire, so you'll need to buy those separately. I took the opportunity to use all black. There's just something attractive about two black wires and a black XT60. Just make sure you've got the polarity correct!

Solder the wires to the XT60 connector first and add shrink tube to cover the joints. Flux and add solder to the battery pads on the 4-in-1 ESC and solder the wires to the pads. I soldered the wires to the pads horizontally, ignoring the vertical grooves.

Try to solder them so the battery lead points out toward the side of the quad. This will require cutting one wire slightly shorter than the other. Solder the capacitor on top of the battery leads. The striped side of the capacitor is negative.

Make sure the capacitor angles upward so you've got room to mount the VTX behind the stack.

Binding the Receiver

Now that you've got power you can add the receiver and bind it. I used the FrSky XM+, but you'll need to choose a receiver that matches your radio.

Solder 3 wires to the 5v, GND and SBUS pads on the receiver. I borrowed some wire from the camera. It's got enough to spare. Solder these wires to the 5v, GND and R3 pads on the flight controller (FC). Refer to the photo for wire placement. Add your flight controller to the stack and re-connect it to the 4-in-1 ESC with the included wire harness. Make sure the arrow on the FC points forward. Bind your receiver Be sure to double check that you don't have continuity between your main battery leads and use a smoke stopper if you have one.

Hold the bind button on the receiver while you plug the main battery in. (It's helpful to clamp this button down with tweezers to free your hand)

Put your radio into bind mode and make sure you're bound. Now that you're bound you can add some shrink tube to your receiver and put it in front of your flight controller. Attach small zip-ties to your front arms and shrink tube the antennas to the zip ties. Secure the flight controller with the included nylon nuts.





Camera

Next we can add the camera. First you'll want to screw the side plates to the camera and mount it onto the frame to measure the wire. Remove the purple wire and connect the wire harness to the back of the camera. Cut the wire giving yourself a little slack to adjust the camera angle. Refer to the photo for wire placement. "VI" stands for video input.

Video Transmitter

Now for the last component, the VTX. Remove the 5V output and GND wires from the harness. We don't need those. We're using the FC to power the camera instead. This leaves just 4 wires. You'll want to use the B+ pad to power the VTX as well as the adjacent GND pad. Use "VO" for video output and use TX6 for the data wire. This allows you to control the VTX via your On-Screen-Display (OSD). Refer to the wiring diagram included with the TBS Unify transmitter.

Camera Configuration

Now that you've wired the camera and VTX you can adjust your camera settings. Plug your quad in and check that you've got a video feed in your goggles. Then, plug the included camera joystick onto the connector behind your camera. Mainly all you want to do is disable the camera OSD. We'll be using the Betaflight OSD instead. Press and hold the up button to access the OSD menu. Disable each option and save.

Finishing Up

Now it's time to wrap it up! Screw the aluminum standoffs to the bottom plate and mount the top plate. Since I used countersunk washers I had to cut deeper grooves into the battery pad. Just make sure it lines up with the holes on the top plate. It's also a good idea to zip-tie the battery lead to the an aluminum standoff to reduce stress on your stack in the event of a battery ejection. Add your antenna and zip-tie it to the top plate, and finally you should zip-tie the motor wires to the arms to avoid snags.

Betaflight Configuration

If you don't already have them, you'll need to download Betaflight Configurator [Download] and the BLHeli_32 Configurator [Download].

First go to the Firmware Flasher and choose "KAKUTEF4V2" as well as the latest stable release of Betaflight. Click "Load Firmware [Online]" and then "Flash Firmware" to update your flight controller. Once complete, click "Connect" On the Ports tab On UART3 click Serial RX for your receiver.

On UART5 set the sensor input to "ESC".

Set the UART6 Peripherals to "VTX (SmartAudio)".

Click Save and Reboot On the Configuration tab Under ESC/Motor Features select DSHOT600

If want to fly "props out" with reversed motors, select "Motor direction is reversed" below the illustration. (This is optional)

Under System configuration set PID loop frequency to 8 kHz.

Under Receiver choose your receiver mode. For the XM+ choose "Serial-based receiver" and "SBUS"

Under Arming set the Max arm angle to 180 (Only if you keep the accelerometer turned on)

Under Other Features enable: Airmode, OSD, ESC Sensor, Anti Gravity and Dynamic Filter

Under DSHOT Beacon Configuration enable RX set

Click Save and Reboot On the Power & Battery tab Set the Current Meter Source to ESC Sensor

Set the Voltage Meter Battery Scale to 112. Go to the CLI tab and paste the following commands to map the motors:

resource MOTOR 1 A03 resource MOTOR 2 B00 resource MOTOR 3 A02 resource MOTOR 4 B01 save

To complete the remaining steps you'll need to apply lipo power to your build:

On the Receiver tab ensure your pitch, roll, throttle and yaw are being applied correctly. Adjust your transmitter and Channel Map as needed. I like to add about 4 or 5 to both deadbands to smooth out gimbal jitter. On the Modes tab Assign an Aux switch to arm and disarm your quad.

Assign another Aux switch to enable Horizon or Angle mode if you need them.

Assign the Beeper and "Flip over after crash" to a 3rd and/or 4th switch. I like to assign them both to a single 3 point toggle switch with the beeper on the last position. Otherwise it'll beep when you don't have your radio on. On the Motors tab enable the motor test and apply a small amount power to check the rotation of each motor. Take note of any that need to be reversed. Disconnect from Betaflight Configurator and open BLHeli_32 Configurator Connect and Read Settings

Reverse each ESC that needs to be reversed. This is done by un-selecting the other ESCs at the bottom and saving them one at a time.

Set the PWM Frequency to 48kHz of each ESC.

As an added bonus you can change the ESC startup music.

Reconnect to Betaflight Configurator to test the motor directions. On the OSD tab Check all of the features you want and arrange your OSD as desired.

And that's it! The default Failsafe settings are generally fine, but make sure they work by arming your quad, applying a small amount of throttle and turning off your transmitter. It should shut down after a short moment.

Challenges

This was a really straightforward build. The soldering can be a slight challenge as the pads are pretty close together. Just take your time and apply flux when the solder starts to stick to your iron. To solder to the flight controller add a small ball of solder to the pad then push the wire straight down through the ball into the hole below. Lightly tug at each one to make sure you've got a solid connection. Other than that I had a hard time getting a nice clean ball of solder around the battery leads. I prefer square battery tabs, but these get the job done.

Maiden Flight

When installing your props make sure to pay attention to the rotation direction illustrated on the Configuration tab in Betaflight. If you're flying "props in" then the leading edges of each prop needs to rotate toward the front and rear of the quad. If you are flying "props out" then the leading edge need to rotate toward the sides of the quad. Make sure the lock nuts are tight but not extremely tight. Conduct your first hover test in a safe place where you won't damage anything or hurt yourself and then you should be ready to enjoy some FPV!

Don't want to build?

Rotorbuilds has partnered with GetFPV to offer an RTF version of this quad. Get it pre-built and ready to bind to your FrSky radio here: TBS Source One Quadcopter 6S RTF.