FPV frequency tips for flying with friends.
One of my favorite things about racing FPV drones in NZ is the community. Flying and racing with others is some of the best fun you can have in this growing sport, but once you add other pilots into the mix, some problems can arise. Having a good FPV video feed to your goggles is one of the most important things you need in order to stay in the air, and this can sometimes be compromised with more pilots around. But don't worry! These issues are easy to fix, and I'm going to tell you how!
The first step is knowing how to change channels on your VTX (Video Transmitter). Most times when you arrive at a spot with new people, you figure out what channels everybody is on, and from there you can change channels so that there is no interference when you're flying. So knowing how to change channels is important. Your video transmitter will generally come with a manual on how to change channels.
The next step is knowing, at least roughly, how the channels work. Pretty much all FPV video transmitters and receivers have the same channels on them and all the individual video frequencies are sorted into "Bands". There are 6 Bands nowadays, and each band is basically an assortment of 8 video frequencies.
The bands are:
F (Sometimes called "Airwave")
C (Usually called "Raceband")
L (A lower frequency Raceband, but it's basically illegal so don't even bother!)
The most common bands are E, F and Raceband (C), so chances are you'll be using channels from those bands.
Now, each band has an assortment of frequencies that it uses, but they're slotted in there from channel 1 to 8, so for example, you might be on F4, which means you're on the F band, using the 4th frequency in that list.
I could explain how to figure out what frequencies work best together, BUT luckily, other people have done that for me already! So I have a set of channels for you to use when you fly with other people. As long as everyone is using one of these channels, video feed issues shouldn't exist.
For 5 people, you should use:
5685 E 2
5760 F 2
5800 F 4
5860 F 7
5905 E 6
And for 6 people, you can try adding:
5645 E 4
This set of channels is called IMD 5 frequency set (Or IMD6 if you add the 6th channel), and it's been tested to cause the least interference between video channels.
The bigger numbers next to the channels are the actual frequencies in mHz. If you have a look, you can see that there is at least 40mHz difference between each channel, which is one of the reasons why they work so well together.
Another important thing to look out for is your vTx antennas. Some antennas are prone to "bleeding" their signal onto other frequencies. Antennas like the linear dipole antennas are classic examples, the way they're constructed makes them super prone to bleeding video.
A really badly damaged antenna can be an issue too, so just check your antennas and make sure they're in good condition!
Good antennas to use are the TBS Triumph antennas, or Pagoda style antennas. The Triumph antennas are super durable, but also a little more expensive. Pagoda style antennas are cheaper, but also a little less durable.
Finally, we have something called "output power". Video transmitters come in different varieties of output power. It's basically just how hard the video transmitter pushes out the signal.
Commonly, you'll get a 200mw (mw, or milliwatt, is the output power) VTX, but a lot, if not most, of popular VTXs have a feature where you can switch the power output from 25mw, up to 200mw or even 800mw.
It's important for everyone to be on the same output power, because if someone is running a higher power output (say, 200mw), that will bleed over anyone who is on lower power (25mw). Or the other way around. If someone is using 25mw, while everyone else is using 200mw, Mister 25mw will get too much interference!
In conclusion, if you want to avoid video feed issues while flying with others, you need to:
- Get to know your VTX; how to use it and change channels.
- Use channels that work well with each other; IMD5 or IMD6 are your best bets
- Use the right antennas; Pagodas are good and they're cheap, but there are other good antennas like the TBS Triumph, and antennas from bigger brands that work great too!
- Make sure everyone uses the the same power output!
These tips should help you have an interference free day!
Bonus! Try to avoid powering up your drone close to other people who are flying. If your frequency is physically too close to someone who is already flying, it can overpower their frequency and cause them to lose video, which isn't fun! You should also warn people that you're powering up, so they can brace for the possibility of a little interference.
Thanks for reading, and I hope this helps you with any video difficulties in the future!