My constant pursuit of finding the best antenna for the drone got me to buy a bunch of these antennas. Initially I did not understand why the drone would lose its signal even before 300 metres.
Well I have decided to disassemble the antenna and the reason why is staring you in the face. Its made from tin foil and a bunch of wires
Bear in mind that I paid around £15 for each. If I remember correctly the antenna is rated as 8 dbi for 2.4ghz and 11 for 5.4ghz.
Stay clear of this junk
Today I have received an antenna under the brand name – “Cool Making”. I have purchased it from eBay a few weeks ago for £38, which is nothing compared to Fpvlr which sell a comparative antenna for £117 with lower Dbi rating (which in reality means nothing) .
On eBay, they sell several variants of the antenna in either black or white and for DJI Mavic, Phantom 3 Adv/Pro, Inspire 1 and for Phantom 4 Pro.
The build quality looks quite good and according to my measurements, it should fit perfectly to my modified GL300A controller.
They promise the range of over 7km range unboosted. My previous best distance was 2.6 km using Alpha directional antennas (could have gone more but I chickened out having never flown that far. PS: I’m flying in the UK so the CE limitations apply in my case
I will wake up very early tomorrow to perform the same test I did for alpha patch antennas. I will fly the same route and altitude as I did before. If I get close to 4km I will be very happy and I will stop searching for new antennas. I never fly that far, always within VLOS, but I hope that the video quality will improve
On paper, these offer 16 Dbi so they should take my drone much farther and I hope the battery will be the limiting factor.
Finally, I had some time yesterday to perform the mod. Together with all the recording, it took me around one hour and it’s actually quite easy. You just have to take your time when removing the glue around the existing connectors and it’s a bit tricky to connect the new wires.
Here is how the controller looks when open
When hooking up new connectors you have to make sure that they are absolutely parallel to the board, then apply pressure and you would hear a click. I have also used a glue gun, which I picked up for around £7 and I think it’s a must.
I have also removed the old 2.4 GHz antennas, which are actually very small. No surprises here, in my case the video feed would cut out after 100 metres.
The kit comes with two directional 2.4 GHz 7dBi antennas for the video feed and one 10 dBi 5.4 GHz antenna for controlling the drone.
The mod promises significantly longer range – up to x4 times! I’m hoping to have the video feed up to 0.5km and control range of around 1km.
The best thing about the mod is that it allows using any standard WiFi antennas and further extend the range by using WiFi amplifiers.
Here is the recording of the job, compressed into 5 mins
Return to Home
If you are finished flying and want the drone to land itself from where it took off, you need to activate the return to home function (RTH).
To activate the RTH, quickly toggle the S2 switch back and forth. The controller would then start beeping and the return to home procedure will be initiated.
To cancel RTH toggle the S1 switch back and forth and move the S2 switch to the uppermost position. The controller should then stop beeping and the drone will simply hover until you take over.
On DJI drones the GPS location is used by the aircraft/remote control to adjust the power output of the signal transmission to meet the local regulations. In the US, the governing body is FCC (Federal Communications Commission) in Europe it’s CE (Conformité Européenne). Doing that allows DJI to sell the same device in both markets.
In case of Phantom 3 Standard, when I say “power output” I mean both the 2.4GHz link – the bi-directional communication between the aircraft through the remote control, and the 5.8GHz control signal – one-way link to the aircraft.
FCC seem to be far more generous and allow for higher levels of power output by consumer devices. CE, on the other hand, are more strict in that regard. What this means is that, if a DJI drone detects that it’s outside of the US, it automatically applies the CE standards, even though you might not be in Europe. It either goes by FCC or by CE regulations. How and when exactly this limitation is applied is somewhat of a mystery to me (I’m still researching this topic, so please do let me know in the comments if you know the specifics). This lowers the power output of the transmission on both, the aircraft and the the remote control from 27 dBm to 17 dBm – almost by 40%! Inevitably that results in reduced range for those of us operating our drones outside of the US.
If you are looking to buy a new Phantom 3 Standard you probably wouldn’t find it for anything cheaper than £450 – 500. Yes, there is always eBay, but then you are buying a used and most probably abused product without any warranty.
I got mine from scan.co.uk for £328. OK it’s not technically brand new but refurbished. What it means is that it might have been returned, the box has already been opened, hence the price reduction. First of all it’s a reputable company, they give you a warranty and their customer support is brilliant.
For example my box came without a charger. I gave them a call and they sent me one the very same day, no questions asked. I could have claimed the £124 battery is missing and I guess they would have sent me one (I don’t suggest you do that, karma will get you!).
Apart from that minor issue, the drone came in the original box with all the standard accessories (propellers, stickers etc) and it looked absolutely brand new.
I have no affiliation with them whatsoever, just telling you how I got my drone.