My second question. New here so need all the advise I can get.
What is the best frequency to use. I was flying in my usual area the other day and a few times thw display told me I had lost connection, I move the transmitter slightly and it came back. I have just found out how to change to 2.4 MHz as I was on 5.8 MHz so haven’t flown on the 2.4 MHz yet, would it have given me better range.?
2.4 but with the FCC mode enabled. I’ve never had an issue
1 Like
Would rather not enable American mode if I don’t have too
I use 2.4 and haven’t had an issue despite it being a more crowded band width.
What’s the general view of enabling FCC mode ?
It literally doubles the signal strength. For me it’s a no brainer. There are no disadvantages that I’ve encountered.
1 Like
I am using iOS and after some research it doesn’t look that easy to convert to FCC.
1 Like
If you are flying within the UK the maximum distance your UAV should be from you is 500m
2.4 GHz is more than enough power. Yes it is true this band can get very busy, however the digital coding of your signal between your controller and UAV will cope easily
GI think that is he answer I was after. I don’t fancy flying out of sight . Thanks for the advise.
Copied and pasted from Netgear.
The 2.4 GHz band provides coverage at a longer range but transmits data at slower speeds. The 5 GHz band provides less coverage but transmits data at faster speeds. … However, higher frequencies allow data to be transmitted faster than lower frequencies, so the 5 GHz band allows you to upload and download files faster.
For control range 2.4 is better…
1 Like
A brief history.
At one time most hobby RC control was on 35MHz and 74MHz. The frequencies were allocated as to what you were using, i.e. 35MHz was generally used for flying things and 74MHz for wheelie and floaty things. On these frequencies there were set analog channels which meant that a limited number of people could fly, roll, or float together at anyone time in the same area.
As digital electronics and UHF RF devices got smaller, and more importantly cheaper, manufacturers started producing digital 2.4GHz equipment. These systems provided a high degree of immunity from co-located interference allowing for more users to do their thing. As these systems matured so did the modulation methods and protocols thus increasing the robustness.
Up until the introduction of the Phantom 2 Vision and Phantom FC40, 99.9% of RC control was on 2.4GHz, though the long range guys used 433MHz and 459MHz. Both the P2Vision and the FC40 used 5.8GHz for control as the fitted cameras used 2.4GHz WiFi to stream the video. The reason for this was that at this time there were very few, if any, mobile devices capable of using 5.8GHz WiFi.
Today it is generally the norm for WiFi controlled drones to be able to switch between 2.4GHz and 5.8GHz. The WiFi devices used are cheap and generally both frequencies are supported in the same package, also the manufacturer doesn’t have to re-invent the wheel as they can just fit prebuilt off the shelf WiFi devices into their drones.
Both frequency allocations have their own strengths and weaknesses. These are dictated both by the laws of physics and by the regions they are used in.
In Europe the CE standard is that 2.4GHz is limited to 100milliwatts to the antenna, and 5.8GHz is limited to 25milliwatts. Where as in the USA 2.4GHz is allowed 400milliwatts and 5.8GHz up to 600milliwatts, to the antenna. The 2.4GHz, power for power, offers greater range than 5.8GHz due to the greater absorption effect as you go higher in frequency. But the 2.4GHz band is only 80MHz wide and has many users. This means that the bandwidth available to each user is small. In realistic terms this means that the received live video will be lower resolution and have increased latency due to the lower data rate. On 5.8GHz the amount of spectrum available is in the 100’s of megahertz. This means that the amount of data a user can send is much greater, generally resulting in a higher resolution of the received image and less latency. However in Europe the range is significantly less than than that of 2.4GHz because of the piddling candle power limits allowed on this allocation.
Now I could wax lyrically about the inverse square law and how to calculate path loss, but only if you start to piss me off. 
Nidge.
4 Likes
Thanks Nidge for the information. Seems that here in Europe we have drawn the short straw (range).
2 Likes
I don’t believe there’s anything specific to video but the power limits for any unlicensed radio device on 2.4GHz, whether that’s WiFi, RC, etc, is 100milliwatt, 20dBm, -10dBW, for OFDM systems and 18dBm (60milliwatts) for continuous code keying systems, to the input of the antenna. Some European countries, e.g. France, did have a limit of 10milliwatt on 2.4GHz but I think they may have revised this.
Nidge.
Copy and paste from FPV-U.K.
VTx – Video Transmitter – Your transmitter forms half of your video downlink to the ground. 10mW is the UK legal limit for licence free 2.4GHz video transmission and a good quality system can give 450 meters range, up to 1km with high gain antennas and a very well setup system and a favourable RF environment.
Copy and paste from E.T.S.I. (European Telecommunications Standards)
“There exists two EIRP power limits for the 2.4 GHz band, one for 802.11b rates with CCK modulation (1, 2, 5.5 and 11 Mbps) and one for 802.11g/n rates with OFDM modulation. The limit is set to 20 dBm (100 mW) for OFDM and 18 dBm (63 mW) for CCK.“
WiFi drones use the OFDM WiFi Standards where as the majority of Hobby Grade RC systems use frequency hopping and/or spread spectrum which would be classed as Continuous Code Keyed modulation.
I think the confusion arises as the specification also references power levels as “10milliwatts per Megahertz” which is not the same as EIRP (Effective Isotropic Radiated Power).
Nidge.
I’ve been fiddling around with FPV (going to try FPV on an Inspire with my mate as camera operator tonight). The 5.6GHz limit is 25mw.
So why have all the TX I’ve looked at been variable power - up to 1200mw in one instance. What licence would I need for one of those. And how likely are Ofcom to prosecute if I run illegally?
In layman’s terms…
Transmitting video from the air to the ground is 10mW on 2.4G the RC control link is 100mW, transmitting on 5.8G video from the air to the ground is 25mW.
It’s all to do with licensing, unless there has been a change in the air to ground video transmission regulations…
When I started flying FPV 10-12 years ago we were using security cameras with their transmitters which were set to 10mW. I believe the wireless security cameras are still on 10mW…
FCC which is U.S.A is higher power levels and illegal in the U.K…