In this post we will discuss the differences in frequency bands for FPV. You may want to choose one over the others due to factors such as range, cost, antenna size and regulations. There is no “best” frequency, only the one that works for your particular case.
To fly FPV, we need two wireless signal links, one signal is to control the aircraft, and the other is the video link coming from the aircraft back to the pilot. These two signals have to be on different frequency bands so they wouldn’t interference with each other.
The most common frequency combo is using 2.4GHz for radio control, and 5.8Ghz for video. But did you know that there are other frequency bands that are used for FPV as well? In this article we will take a look at the frequencies used specifically for FPV.
How Many FPV Frequency Bands?
Usually people decide on what frequency they want to use before picking FPV system equipment such as video transmitters (VTX), video receivers (VRX), and antennas. These are the common frequencies used in FPV.
- 900 MHz
- 1.2 GHz / 1.3 GHz
- 2.4 GHz
- 3.3 GHz
- 5.8 GHz
I don’t really know the exact figure, but if I have to guess, I’d say at least 80%-90% of the people flying FPV are using 5.8GHz. I will explain why in the following chapter.
Differences in FPV Frequency
Generally, lower FPV frequency allows for longer range and can penetrate obstacles more effectively. However, the higher frequency allows more information to be transmitted in the same amount of time, and therefore the image looks better.
Unfortunately, not all frequency bands are legal for hobbyists, and there are also restrictions on how much power is allowed to be transmitted.
The laws can be different in every country, so find out about your local regulations before getting into FPV. In this article, I will use the United Kingdom as an example.
Despite being the highest frequency in the list, I want to talk about 5.8 GHz first because it’s confidently the most widely used frequency in FPV. It’s so popular for a number of reasons:
- Lots of options when it comes to gear, these are available in many different sizes, power level, and features
- Antennas are very compact and light weight
- Decent (enough) range for multirotors
- Legal to use in many countries (under certain power)
- Compatible with 900MHz and 2.4GHz control signals
The antennas for 5.8GHz FPV system can be made extremely compact and light weight, because of the higher frequency.
5.8GHz also has the widest product range – I am collecting specs of all new VTX in this spreadsheet, it’s an ever growing list. Some VTX have up to 72 channels in 5.8GHz as explained in this article, that allows you to fly with more people at the same time thanks to the possibility of having wider frequency separations.
It doesn’t affect 2.4GHz or 900MHz radio control links much, making it a great companion frequency.
5.8GHz has a decent range to power ratio, but because of the high frequency, penetration property is very poor. Therefore, flying is mostly restricted within line of sight, and it’s only ideal for short range flying mostly, maybe medium range if you can manage to stay line of sight.
Further Reading; Tips on Flying Long Range FPV
If you want to have really good range with 5.8GHz, using decent FPV Antennas is extremely important.
Perhaps not the most noticeable benefit, but 5.8Ghz does have slightly better video and audio quality than lower frequency bands due to the higher data rate.
The lower the frequency, the greater the range and signal penetration, so in theory, 900MHz should be the best in the list in that regard. However it’s the least used frequency band for FPV because of the huge the antennas, and the lack of equipment availability.
1.2 GHz / 1.3GHz
1.2GHz and 1.3GHz provide great range and signal penetration ability. However the antenna is also pretty big, and you could also run into trouble pairing this next to your 2.4Ghz radios, as they sometimes interfere with each other. Low pass filters are often used to solve this problem.
But beware that it is illegal to use for FPV in many countries, including the UK. People in the US are allowed to use 1.3GHz for transmitting video/audio only if they have a HAM license.
You can get decent range out of 2.4GHz, and it has a very good range to power ratio. It was much more popular back in the days with 27MHz, 72MHz and 433MHz radios, because they wouldn’t interfere with each other. Less so now as we FPV hobbyists mostly use 2.4GHz for radio control.
The penetration ability is not as good as 900MHz/1.2GHz frequency bands, but still much better than 5.8Ghz.
However, given the fact that it is the most used band in many different devices and equipment, such as WiFi, Bluetooth, RC transmitters/receivers, and even Microwaves, you could run into some serious interference issues. So usually if you decide to go with this band for FPV, you need to choose a different frequency for your RC transmitter other than 2.4GHz, such as Crossfire and R9M.
3.3GHz is a relatively new frequency for FPV. It’s potentially a good alternative to 1.2GHz and 5.8Ghz, as it’s a “happy middle ground”. It also doesn’t interfere with 2.4Ghz radio control links, nor the 900MHz. However, 3.3GHz is illegal to use in many countries for FPV.
Legal FPV Frequency and Power Level In The UK
Not only are there certain frequencies that are illegal for FPV flying, but also constraints on the video transmission power level as well. For more detail check out this PDF.
2.4Ghz and 5.8Ghz frequency bands are okay to use for FPV in the UK, but there are power limits: for 2.4Ghz, the max power is 10mW. For 5.8Ghz the max power allowed is 25mW. (information from here)
It’s worth knowing that even in 5.8Ghz, some channels are outside of the legal frequency range. So make sure you know which ones are allowed in your country.
Conclusion – What Frequency to Use for FPV?
At the end of the day, it depends on what kind of flying you are planning to do – longer range, lower frequency.
If you want to do it legally, then you don’t really have much choice. Most decent FPV equipment is basically illegal to run due to restrictions on transmission power and frequency.
That’s why you see most people are using 2.4 GHz for Radio control and 5.8 GHz for FPV, for reasons of being legal and the cheapest options.
It’s not uncommon to see people flying FPV using an illegal frequency and transmission power without getting caught (such as 5.8Ghz 600mW). Let’s face it, regulations regarding RF transmission is hard to police. Anyway, you should always follow the law, and don’t do anything unsafe or stupid.
- Jan 2014 – article created
- May 2017 – article revised
- Jan 2019 – Updated info about 5.8Ghz