I will show you step by step how to build an FPV drone that uses DJI’s FPV system. I will list all the components, explain how everything is connected, and the tips and tricks that will help you in your future FPV drone builds.
Can Beginners Build an FPV Drone?
You can buy a pre-built drone, but you won’t learn anything. By building it yourself, you will learn how everything fits together and it enables you to repair it later on.
Building your first FPV drone is going to be hard and could take hours, or even days to complete. When you encounter a problem, you might take advice from experienced pilots, or ultimately end up finding your way by trial and error. Either way, the journey is going to be extremely rewarding.
Learning the Basics
The goal of this article is to teach you the steps and basic knowledge of building and setting up a mini quad from scratch.
But before we begin, please make sure to read this tutorial to get a basic understanding of FPV drones: How to get started with Drone Racing and Mini Quad
If you ever see an unfamiliar acronym, you can try looking it up here: Acronyms and technical terms in FPV.
I have other build guides using separate ESC and Frsky Receiver. I am currently working on a new build guide using 4in1 ESC and analog FPV system, which should be ready by end of April.
No 3D Printer? No Problem!
The good news is that this build doesn’t require any 3D printed parts.
But you can use 3D print parts if you want, and they can make it a lot easier to build, and it just look cooler.
Anyway I will show you all the steps how to build this FPV drone with and without 3D printed parts.
Table of Content
I will be using these parts in this tutorial.
Disclaimer: the following table contains affiliate links. It doesn’t cost you anything extra, but it gives me a small commission when you make your purchase using these links.
|Frame||1x TBS Source One HD (V4)||GetFPV | Amazon | NBD|
|FC / ESC||1x Speedybee F7 V2 + 45A ESC||Banggood | RDQ | Amazon|
|Motors||4x RCINPower Wasp 2420KV||Banggood | GetFPV | Amazon|
|Propellers||4x HQ 5.1×4.1×3||RDQ | GetFPV | Banggood|
|Receiver (RX)||1x Crossfire Nano||GetFPV | Amazon |NBD|
|FPV Setup||1x Caddx Vista + Nebula Pro||Banggood | GetFPV | RDQ|
|Misc Parts||1x XT60 Pigtail (14AWG 8cm+)||Banggood | Amazon | RDQ|
|1x Buzzer||Amazon | Banggood|
|1x Battery Strap (20x220mm)||Banggood | Amazon|
You also need the following stuff that you can easily find on eBay or from you local hardware store.
Not using 3D printed parts:
- 4x 2mm wide zip ties (15cm or longer, for Vista)
- 4x M2 1mm thick washers (for camera)
- 2x M2 5mm screws (for camera)
Using 3D printed parts:
- STL Files: https://www.thingiverse.com/thing:4844808
- 4x 25mm m2 bolts (for vista)
- 4x 10mm m2 nylon standoffs (for vista)
- 4x M2 nylon nuts
I have chosen the Source One for this build because it’s one of the cheapest frames available. Also, because it’s open source, the design has been improved considerably over the years by the community, and it’s now compatible with the latest components.
This V4 HD version is designed for the DJI Air Unit and Caddx Vista. It also comes with a spare set of arms (different width), so if you break an arm you will have spare! Not bad for $27!
The other cool thing is there are a ton of 3D printed part designs available on Thingiverse for enhancement.
FC and ESC
I like getting an “FC stack” that consists of a flight controller board and a 4in1 ESC board, because there is minimal amount of soldering, it’s plug-and-play and it just works!
I selected the Speedybee F7 V2 because it’s feature-rich, it has built-in Bluetooth so that you can configure Betaflight from your phone in the field, and it’s plug and play with DJI Air Unit.
It’s important to get an FC that has a dedicated BEC (9V output) for the DJI Air Unit and Vista. Although you can power the Vista directly from LiPo battery, it’s less likely you are going to damage it from voltage spikes when using a BEC. And the Speedybee F7 V2 has that.
Motors these days perform very similarly, the main difference is usually the build quality. For a 5″ build, motor sizes such as 2306, 2207, 2208 are all good options here. The other consideration is motor KV, we are using 2400KV in this build because we are planning to use 4S LiPo battery. For 4S, 2300KV to 2600KV are commonly used, the higher KV is more aggressive and power-hungry.
6S FPV drones are also popular (using 6S LiPo battery), and you’d probably want lower KV motors such as 1800KV. But the higher voltage makes the drone harder to tune and it can sometimes cause more issues, I really don’t think it’s beginner friendly. Therefore I’d recommend 4S as your first build.
There are two VTX options when it comes to DJI FPV System: the full size DJI Air Unit, and the Caddx Vista. However, DJI announced in March 2021 that they are discontinuing the Air Unit, so the Vista will be the only option remaining.
As for cameras, there are a few more options, but the latest Nebula Pro from Caddx is the best in my opinion. It has the same image quality as the original DJI camera, and yet a couple of grams lighter.
You can buy the Nebula Pro and Vista as a combo, and it includes the VTX antenna too, so that saves us a lot of trouble.
Your choice of radio transmitter will determine what receiver (RX) you can use. If you follow my radio recommendation, then your radio should support TBS Crossfire.
Right now, I recommend TBS Crossfire because of its top notch performance, reliability and ease of use. I exclusively use their Crossfire Nano receivers in almost all my FPV drones, because they are very compact, and gives me more than enough range.
To use Crossfire nano receiver, you will also need to get a Crossfire TX module that plugs into the module bay on your radio.
Other FPV Equipment
You will also need the following accessories to fly a quadcopter in FPV. You can take a look at what gear I use everyday for some ideas. But here I will summarize what you will need.
A Radio Transmitter (Buyer’s Guide) is used for controlling the drone, right now (April 2021) I recommend getting the Radiomaster TX16S (see my review). It’s affordable and versatile. It does basically everything you need in FPV.
To use DJI FPV System, you will need a pair of DJI FPV Goggles (see review), V1 and V2 will work equally well for custom built FPV drones.
As for LiPo batteries, some 4S 1500mAh would be perfect, see this post for my LiPo Recommendations. Make sure to spend time learning about LiPo in this Battery Buyer’s Guide, because if you don’t handle them carefully they can be dangerous.
If you want to see other mini quad parts that I have tested and recommend, check here: https://oscarliang.com/tag/recommend/
Tools and Supplies for Building FPV Drone
Here is a basic list of tools that are essential for building FPV drones.
- Soldering Iron and solder
- Hex drivers set (Buy from Amazon)
- A small Phillips head screwdriver (Buy from Amazon)
- A pair of scissors for stripping and cutting wires
- Electrical tape (Buy from Amazon)
- 3M double sided foam tape (Buy from Amazon)
- Multi-meter (Buy from Amazon | Banggood)
- Zip ties
If you want to get serious, here’s a complete list of tools that you might find useful.
Steps of Building FPV Drone
Click the link will take you to the section in this article:
- Frame Preparation and Assembly
- Installing Motors
- Wiring Diagram
- Installing ESC
- Installing FC
- Testing Motors and ESC Setup
- Setup Receiver
- Connecting FPV Setup
- Finishing off
- Using 3D Printed Parts
- Setting up Betaflight
- How to Tune Mini Quad
- Learning How to Fly a Racing Drone
1. Frame Preparation and Assembly
It’s optional but a good practice to “prepare” the frame:
- First, sand down sharp edges on carbon fibre pieces, especially the outer side of the arms, and plates, sharp edges could cut your wires and battery strap in a crash. The chamferred edges can also prevents carbon sheet from delamination
- After sanding, wash all carbon fibre parts in soap water to remove any carbon dust that remains (note that carbon fibre is conductive), then dry with towel
Assemble the frame by installing the 8 aluminium standoffs.
Then the arms and bottom plates.
2. Installing Motors
You can now mount the four motors to the arms.
It’s recommended to use loctite (thread locker) on motor screws. That’s because motors make vibrations and there is a chance those screws can wiggle free over time. Make sure to use the blue liquid one, the red liquid is intended for permanent use and you will have a hard time undoing those screws!
There is no need to use washers.
Finally, make sure motor screws are not touching motor winding – here is how to check if your motor screws are too long.
3. Wiring Diagram
Plan on how to connect all the components, draw the connection on a piece of paper. If you are using the components I recommended, here is a wiring diagram you can follow.
You can try to “dry fit” all the components – install them in the frame without actually connecting and soldering the wires. This allows you to see how long the wires need to be, and it allows you to spot any potential issues with spacing.
4. Installing ESC
With the Speedybee F7 V2 FC I am using, it comes with these long bolts for the FC stack, to replace the four original screws in the frame.
Insert the o-rings (comes with the FC) in the long bolts.
Install the 4in1 ESC, but watch out for orientation. To identify which side of the frame is the front, just look for the cut-outs for the camera mounting plates. The 4in1 ESC should have the positive/negative pads facing to the back of the frame.
Check the bottom of the ESC, and make sure it’s is not touching anything.
You are about to do some soldering. If you are new to it, please see my tutorial, How to Solder for Beginners.
Check how long the motor wires need to be, and cut to length (it’s a good idea to leave some slack).
Then strip the wires (around 2mm) and tin the ends.
Tin all the solder pads on the 4in1 ESC. It’s good practice to cover area of the board where you are not soldering with tape. This will prevent solder accidentally dropping from your soldering iron onto components and causing electrical shorts.
Solder the motor wires to the ESC. Don’t worry about wire order and motor direction for now, we can change it later in the software.
Solder the XT60 power lead and capacitor to the power pads on the ESC. Watch out for polarity (positive and negative). The FC already comes with an XT60 power lead, unfortunately it’s not long enough, so I had to get a longer one, ideally 8cm or longer.
You may wonder, “why solder a capacitor to the power?” Well, it’s for soaking up voltage spikes and reducing electrical noise generated from the motors and ESC. Even if your mini quad is “super clean”, when you have a bent prop, you will begin to get more noise from the motors, and a capacitor can have you covered in situations like this.
See this post to learn more about why adding capacitors to mini quad.
- Use a good amount of solder and solder flux (solder paste) for the large pads, and make sure the solder joints are shiny and full; if you can see the wire strands, it’s a sign that you haven’t applied enough solder
- If the solder “sticks” to the tip when you remove it from the joint, then you should apply more flux
- It’s okay to use high temperature when soldering large solder pads like these, the important thing is to make it quick and avoid heating the pads for too long (I personally use 450°C (840°F) for motor wires and XT60, and 360°C for signal wires)
This is what it looks like when the motors and battery plug are all soldered to the ESC.
5. Installing FC
Solder the RX to the FC.
I will be mounting the RX at the rear of the quad, so make sure the wires are long enough. Of course you can mount it anywhere you see fit, there’s a lot of free space in this frame.
Install the flight controller on top of the 4in1 ESC, make sure the arrow on the board is pointing forward. Connect the 4in1 ESC to the FC with the ribbon cable provided.
Solder the buzzer to the FC.
To mount the buzzer and capacitor, I simply use some double sided foam tape and just stick it onto the bottom plate.
Don’t block the hole in the buzzer with the tape.
With the capacitor, you can also use a zip tie to strap it to a standoff.
Put nylon nuts on the FC. Don’t over-tighten it, just touching the rubber grommet is fine. Compressed grommets = reduced vibration damping.
Use zip ties to strap the XT60 leads and RX to the frame.
Mount the RX antenna to one of the arms with a couple of zip ties. Don’t forget to strap the antenna wire to the bottom plate for stress relief too.
6. Motor Test and Setup ESC
Time to test the ESC and motors, which means we will be plugging in a LiPo battery for the first time!
For safety, you should always check continuity first to ensure there is no electrical short. You can do this with a multimeter: put it on continuity mode and use the probes to test the positive and negative terminals of the XT60.
Here is a quick tutorial on what multimeter you should get, and how to test your drone with it.
If there is a short circuit, the multimeter will be beeping continuously. If this happens, you need to find out what is causing the short and fix it. One common cause is excessive amount of solder used on one solder pad and spill over to or touching neighboring pads.
Pro-Tip: sometimes the meter might beep for a split second then stop. That happens because of the capacitors. When you touch the positive and negative pads with your probes, it charges the caps so there will be a flow of current, and the meter thinks there is a short, but when the caps are charged, the beep will stop. If you get a short beep, that’s normal and nothing to worry about, it should be fine if the meter doesn’t continue to beep.
For the first time plugging in a battery, use a smoke stopper (review). This is a great and simple device to avoid magic smoke! Smoke stopper is optional, but it’s a worthy investment that I can’t recommend enough.
Now it’s time to test the motors, but DO NOT install propellers yet!
Plug in a battery, then go to the Motor tab in Betaflight Configurator, and try to spin up the motors one by one (just move the slider to 10-20%), and verify if the motors are spinning in the right direction (instructions).
If a motor is spinning the wrong direction, then you have to reverse it.
There are two ways to reverse motor direction.
You can swap around two of the motor wires.
Or more simply, you can reverse the motor in BLHeliSuite32. That’s why I said earlier it doesn’t matter how you connect the motor wires :)
Here are instructions on how to connect your BLHeli_32 ESC’s to BLHeliSuite.
While we are at it, you can also change ESC settings to optimize performance. The two settings i always change are PWM frequency (to 48KHz), and Motor timing (to Auto). See this post to learn about these BLHeli_32 ESC Settings.
Something went wrong? Here are some troubleshooting tips.
Motors are not spinning at all? Did you connect the battery? If so, did you hear the ESC beeps when you plug in the battery? Did you connect the ESC to the FC?
If all motors are spinning except one, it’s possible that the ESC or that motor is faulty. You can try swapping that motor with a working one on the same quad, this will help rule out whether it’s the faulty ESC or motor.
If you need further assistance, just ask in our forum: https://intofpv.com
7. Receiver Setup
First of all, you need to bind the receiver to the radio (TX module), I have a whole guide explaining how to setup Crossfire, so I won’t repeat it here. Then in Betaflight configurator, you need to do the following:
- Go to Ports tab, find UART1, and enable “Serial RX“
- In the Configuration tab, under “Receiver” section, select “Serial-based receiver“, and choose “CRSF” as the provider
Once that’s done, you want to confirm the receiver is fully working in the Receiver tab. When you move the sticks on the radio, the bars (channels) should move as well.
If the wrong channels are responding, try a different Channel Map, it’s normally either “default (AETR)”, or TAER.
You will need to setup at least two switches on the radio (instructions), one for arming, and the other for buzzer. You might also want a 3rd switch for flight mode. Again, confirm it’s working in the receiver tab, the two switches should show up in channels AUX1 and AUX2.
If you have any questions, post in our forum: intoFPV.com
8. Connect FPV Setup
Let’s move on to setting up the DJI FPV system.
Take the DJI Air Unit cable that comes with the FC, and cut the end and solder it to the Vista.
Here’s the pinout of the Vista:
We won’t connect the SBUS and GND pads in the Vista, so we can cut those two wires off in the cable.
To connect the Vista to the FC, you can follow the wiring diagram.
To install the Vista in the frame, I simply use some 2mm zip ties (ideally 15mm or longer).
And strap the VTX antenna to the frame like this.
The camera cage of the Source One HD frame has a width of about 24mm, which is an unusual design. It doesn’t fit either DJI FPV camera (20mm), or the Caddx Nebula Pro (19mm), and you will need to use some spacers and longer screws.
For the Nebula Pro, I use 2x 1mm washers and a 5mm M2 screw on each side. For the DJI FPV camera, you will probably just need 1x 1mm washer. It will be a tight fit for the top plate later, but you just need to squeeze the two camera plates while pushing down the top plate.
In order to have OSD for displaying battery level and other flight information on screen, you need to configure Betaflight. This page explains how to do it in detail.
Basically in Betaflight configurator, you need to:
- In Ports tab, find UART2, and enable “Configuration/MSP“
- In Configuration tab, under Other Features, enable Telemetry and OSD
- Inside your DJI Goggles, go to Settings, Display and turn on Custom OSD
9. Finishing Off
It’s good to cover/protect the motor wires with plastic sheets. You can cut up a water bottle, or blades from old propellers. This will prevent “prop strike” in a crash, where spinning propellers could get bent and cut the wires on the arm.
Wrap the plastic piece over the wires with electrical tape or zip-tie.
We are almost done! Here is how the quad looks like so far.
Install the top plate and put a battery strap under and through. The Source One comes with battery pad, they sort of work, but if you want something of quality, check out Ummagrip battery pad, it’s very sticky, washable, and the thickness keeps your battery safely away from the bolts.
The finished drone build weighs:
- Drone = 360g
- Drone + 4S 1500mAh LiPo = 550g
- Drone + 4S 1500mAh + GoPro 7 = 670g
When mounting battery, make sure the COG (centre of gravity) is as close to the centre of the drone as possible. To check if you have placed the battery at the right spot, simply grab the middle of the top plate with 2 fingers, and see if the quad stays level.
It’s important to make sure COG is right at the centre of four motors. For example, if the quad is front heavy, the front motors will have to work harder than the rear motors in order to maintain level, and this will impact flight performance.
When installing propellers, be aware of the different CW and CCW props and install them in the correct motors. Otherwise your quad is going to flip over when trying to take off.
5″ FPV drones use M5 nylon lock nuts to hold the propeller on the motor. It can take some effort to tighten down, but you don’t want it too tight, or the prop hub can shutter when you crash. Just tight enough that the prop can’t move is enough.
Using a proper prop nut tool like this can speed things up too.
And we are ready for a test flight!
10. Using 3D Printed Parts
If you want a cleaner and slicker build, you should use 3D printed parts.
I designed most of these parts myself and I will share the STL files in the parts list if you choose to print them, or you can ask someone to print them for you, like using East Sussex 3D Printing Service, you can contact them on Facebook or email: 3dprintsfpv AT gmail DOT com
In this variation, I will be mounting the Vista slightly differently as well, using some 25mm M2 screws and 10mm standoffs.
Mounting the XT60 pigtail and receiver in exactly the same way as before.
Both the Vista antenna and Crossfire Nano RX antenna will be mounted in this 3D printed holder that slides into the rear standoffs. The antenna placement is more optimal for performance.
And another 3D printed part goes on top of the antenna mount, which is for holding the XT60 connector securely in place.
Mounting of the FPV camera becomes much easier with the TPU mounts, no need for washers. There are holders for both buzzer and capacitor too.
It looks much cleaner.
I also printed a GoPro mount (not my design) to get some 4K HD footage.
11. Setting up Betaflight
To setup Betaflight for your first flight, follow the instructions in this guide “how to setup Betaflight for the first time“.
12. How to Tune Mini Quad
Tuning your quad is basically making it to fly and behave exactly the way you want. Betaflight has come a long way, you don’t have to tune your quad and it will probably fly just fine with stock settings. But if you are serious about performance, then you have a few more things to learn! :D
For me, tuning a mini quad is basically going through these settings and get them dialed in:
- RC Rates and Expo
- Other Betaflight settings (min throttle, antigravity, feedforward, throttle boost etc….)
Betaflight has a pretty nice tuning guide, which is a good starting point: https://github.com/betaflight/betaflight/wiki/4.2-Tuning-Notes
My PID Tune
I will share my PID, Rates and Filter so you can give it a try if you want.
My Filter Settings
You should enable RPM filter first, it’s easy to do and almost always improves flight performance instantly.
When changing filter settings, always make incremental changes, try flying it for 20-30 seconds, then land to check motor temperature. If it’s noticeably warm, then you should probably revert back to the previous value. You don’t want to burn your motors :)
13. Learning How to Fly an FPV Drone
If you have little to no experience in flying a mini quad, you should definitely check out these tutorials to get started:
- Practice with FPV simulators
- Tips and Exercises to learn FPV flying
- Finding FPV flying difficult? Here are some advice from different pilots
First ever flight of this quad:
Some of my older FPV videos: