The following piece was written by Jack Brown, is the Chief Pilot at MyDroneLab.com.
How far can a drone go without losing the video signal when flying FPV?
When it comes to the ideal frequency for mini-quads — that’s the famous 5.8 GHz — the best you can expect is 500 meters. But, that means you’re flying in ideal conditions where nothing stands between you and your drone. The moment your drone goes behind a tree, a hill or building, the range will drop significantly and you even might lose your signal completely.
The bottom line is, if you want to do some long range FPV flying, the 5.8 GHz frequency should be avoided. But what if you want to fly beyond 500 meters?
Change the System
For long range FPV flying, you need more than yourself and the drone — you’re going to need a ground station that works on a different frequency. (And bring a spotter with a pair of binoculars.)
The most popular frequencies for long range flying are 1.2 GHz and 2.4 GHz. Personally, I prefer using the first one because it offers you 10km of range. It’s worth noting that 1.2 GHz is generally not recommended because in case the drone goes down and you don’t have a beacon, you’ll easily lose your drone. It is also much more effective when it comes to flying through abandoned buildings as this signal easily penetrates the walls.
However, due to the legality issues and having tough luck with finding the transmitters and receivers that work on that frequency, the 2.4 might be an easier choice.
If you want to achieve long range FPV flights, use a good directional antenna array. This means changing the antenna scheme. If you choose to fly in FPV on 2.4 GHz, I recommend getting the TBS ground station, and combine it with the Yagi antenna (2.4 GHz – 11 dB). It might not be ideal for everyone’s budget, but you will get a really great gadget that is nicely placed in a rugged, metal case, comes with a screen for the video feed, a built-in receiver (2.4 GHz), holes for mounting a tripod, areas for mounting the antennas, all the necessary things you need to connect your FPV goggles, and a USB port for charging your batteries.
The unit is reliable and allows you to focus on your FPV flying while your spotter has something to do — and they can even look at your flight if they gets tired of looking through the binoculars.
You can also fly in FPV using the 1.2 GHz frequency for the video signal, but you will need a separate receiver, transmitter, filter and antenna to be able to “Hide” the video in the 5.8 GHz frequency.
The best way is to use 1.2 GHz omnidirectional antennas, or a cloverleaf on the drone and helical on the ground. This is one of the best frequencies for long range and for getting the signal through walls and trees, but it is not as reliable as 2.4 GHz and is not legal in most states since planes tend to use these lower frequencies as well.
Getting the longest FPV range: don’t forget about the RC transmitter?
If you use 2.4 GHz for your video signal, you will not be able to use this frequency for the control of your drone since you can’t have both video and control signals running on the same “Path”. Essentially, the two will interfere with each other, resulting in a loss of control over the drone and ultimately a crash.
But, fear not as this frequency is not the only one good for drone control. Old school transmitters that work on 433 MHz, or even lower, on 72 MHz, offer a much longer control range. These are known as the Long Range Radio Systems and are the best choice for long range FPV flights.
My recommendation would be the use of openLRSng equipment, allowing you to get an open source system that can be configured easily, through Baseflight similar app for Chrome. Furthermore, in case of a crash, it will act as a beacon and help you locate your drone.
For those who use Frsky Tarantis transmitter, I recommend trying the DTF UHF Hawkeye XJT module. It turns your transmitter into a 433 MHz, 1W radio, and you will have telemetry. It easily drops into the back of your transmitter.
On the other hand, if you are more of a Turnigy 9x fan, then I recommend the same manufacturer only the Deluxe model.
Even if you do manage to make the perfect drone control and FPV system setup, the range can still vary. Your enemies will always be a bad radio environment, bad atmospheric conditions, the angles of the antennas, and so much more.
To make the most out of your flights, beside the mentioned systems and gear, never leave home without the following extra replacement parts and tools:
- Video transmitters
- Batteries for goggles and the ground station (With a battery tester)
- Radio for tracking down the beacon
- Extra cameras if you can afford them (there are many cheap Gopro alternatives that deliver really good video quality)
- Props (A box of them)
- SD cards (As many as you have)
For the toolbox:
- Soldering iron that runs on butane and solder
- Vice grips
- Silicone tape
- Any kind of Super-glue (Locktite would be the best choice)
- Wire strippers
- A whole bunch of zip ties
- Multifunctional screwdriver
- FTDI board
- Laptop with as many USB cables you can get
- Scissors and a knife
- Packing tape
The author of this piece, Jack Brown, is the Chief Pilot at MyDroneLab.com. He is a graduate of the Drone/UAV Pilot Training Certificate program and a member of the Association for Unmanned Vehicle Systems International. Besides having all the necessary technical knowledge when it comes to drones, Jack and his team love to spend the time outside by the ocean, working on new features and teaching others how to pilot these amazing and exciting new robots.