Hi, I am getting to grips with the range on my new MA.  Yesterday I flew a range test in an area well away from properties and sources of interference.  Probably at least 300m to 400m from houses so the standard Wi-Fi signal from any AP's should be negligible.  I was up high on a hill, stood on a concrete bunker at the highest point and flew the MA away so that it was around the same height as me but around 50m over the ground which dropped away as it went.  So perfectly clear line of sight and antennas were positioned as per the manual for best performance.

I was disappointed to see that the video started breaking up at around 400m and the controller completely lost signal with the MA at 550m resulting in the need to RTH.  So I'm thinking what the heck, this thing is supposed to go 4km.

After getting home and researching I see that 4km is only possible with FCC transmission mode, e.g. when flying in the States.  The system detects where you are by the GPS and selects the correct transmission power.  Further I saw that the system had auto selected 5.8GHz and the manual says the range is 0.5km for CE in Europe.  So my test was pretty much spot on, 550m @ 5.8GHz CE.  However with 2.4GHz CE, the manual says I should expect 2km.

I found out how to change from 5.8GHz to 2.4GHz, in DJI Go 4 simply go into the Wi-Fi settings and select manual, then at the bottom of the screen select one of the channels 1 to 13 in the lower part of the range.  The system will then reset Wi-Fi then is fixed to that channel and will operate at 2.4 GHz with a higher transmission power as per manual spec.

So it is peculiar why the DJI auto channel select mode chose the lowest power 5.8GHz in a location where there was no interference from other Wi-Fi systems, resulting in a low 500m range.  Also it did not auto switch to 2.4GHz while flying and detecting poor signal.

At some point I will test in the same location with forcing a 2.4GHz channel pre-take off and report back.

Custom set WiFi to channel 13 under 2.4Ghz. Don't stand on concrete structures as that will probably have metal rods to support the construction and cause interference. Keep the antenna perpendicular to the drone at all times and elevate to 400' AGL the further you fly away. I reached 5,621 feet / 1.71KM / 1.06 miles with my Mavic Air in the UK on Monday and still had two signal bars remaining with no glitches or signal loss when I decided to turn around and manually return. It probably auto selected 5.8 due to the bunker you were stood on!

It will revert to the last setting you had. I wont auto select between 2.4 and 5 it will only autoselect within the band you are on. So if you set 2.4 it will stay on 2.4 everytime you power on but it will autoselct with the available frequencies on that band.
EDIT . Apparently this does jump between bands when you hit an area where 2.4 is congested and IT DOES NOT retain the last BAND setting. Why is this important to know. Well if you are using a 2.4Ghz Range Extender you dont want to be on the 5 band at launch.

Kevjones1959 Posted at 2018-5-11 02:49
It will revert to the last setting you had. I wont auto select between 2.4 and 5 it will only autoselect within the band you are on. So if you set 2.4 it will stay on 2.4 everytime you power on but it will autoselct with the available frequencies on that band.

Really? I turned the drone off at my flight location 20 miles away on 2.4. I switched the drone on in my house upon my return and it auto selected 5.8.

A CW Posted at 2018-5-11 02:56
Really? I turned the drone off at my flight location 20 miles away on 2.4. I switched the drone on in my house upon my return and it auto selected 5.8.

That is strange. MIne does not jump the band. Always stays on the band I last used. I have to manually select 5.
EDITED

Thanks for the input, interesting...  When well away from other Wi-Fi devices I will manually set ch13 and see how far I can go.  Too windy today damn it, I am eager to see it go well over a mile and back along the sea wall!

A picture is worth a thousand words, this is my range test location:

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Not sure how some metal reinforced concrete would cause a favour of one frequency over another, although RF is a bit of a black art so who knows!

Kevjones1959 Posted at 2018-5-11 02:49
It will revert to the last setting you had. I wont auto select between 2.4 and 5 it will only autoselect within the band you are on. So if you set 2.4 it will stay on 2.4 everytime you power on but it will autoselct with the available frequencies on that band.

I really hope it does this, that would be very useful i.e. locked to the highest power band and auto selects the best signal within it.  Easy to keep an eye on, if 5.8 appears on the signal strength indicator I'll know it's switched back to lame mode.

You’re quite close to that residential area too by the look of it - that will impact on the signal. Fly out over the sea if you dare for a better reception. Looks like a great location to fly but perhaps not ideal for a range test.

A CW Posted at 2018-5-11 02:56
Really? I turned the drone off at my flight location 20 miles away on 2.4. I switched the drone on in my house upon my return and it auto selected 5.8.

I believe that IF there is no interference during the auto selection it will stay in the 2.4G if it was previously selected otherwise it will switch to the more clear 5.8G band

That is what I thought as that is exactly what my MA did

Also take off iwatch (apple or android) and put your phone in airplane mode.

The bunker is going to have no effect on WiFi signals. You have direct line of site with the aircraft from there, if should be good.

A CW Posted at 2018-5-11 03:37
That is what I thought as that is exactly what my MA did

Thanks guys. Then I am going to check mine.

Datadogie Posted at 2018-5-11 03:38
Also take off iwatch (apple or android) and put your phone in airplane mode.

Good tips didn't think of that.  At least turn off phone Wi-Fi and Bluetooth as they are on the same frequencies as the MA.  Cell network and data should be fine though?  I wondered if the GPS ephemeris data might be downloaded from the net via the app to the MA in order to speed up acquisition.  If not, other than live streaming there is no need for mobile network data and that would stop annoying facebook / WhatsApp messages interfering with my concentration!

AndrewUK Posted at 2018-5-11 03:43
Good tips didn't think of that.  At least turn off phone Wi-Fi and Bluetooth as they are on the same frequencies as the MA.  Cell network and data should be fine though?  I wondered if the GPS ephemeris data might be downloaded from the net via the app to the MA in order to speed up acquisition.  If not, other than live streaming there is no need for mobile network data and that would stop annoying facebook / WhatsApp messages interfering with my concentration!

It downloads when you connect. Once you ready to go you can swipe your menu and enter Airplane mode. Would be cool if DJI Go had an Airplane mode setting.

Kevjones1959 Posted at 2018-5-11 03:42
The bunker is going to have no effect on WiFi signals. You have direct line of site with the aircraft from there, if should be good.

Metal is a conductor. That means it absorbs electricity. As radio waves are electromagnetic, metal also absorbs those. It is the conductive capacity of copper wire that makes the receiving antenna capture the incoming radio signal. The same is true for other metal objects, although those other objects are not connected to any mechanism to interpret the radio waves into data or sound, and so the waves just stop there. Stand on top of a bunker with reinforced metal concrete and it WILL affect the signal. That is why DJI themselves and every credible pilot on this forum advise never to take off near metal structures - which will also impact on the performance of the compass. It may also explain why I can fly over a mile with my MA not near any metal objects yet the OP can't get further than 550 metres...

AndrewUK Posted at 2018-5-11 03:43
Good tips didn't think of that.  At least turn off phone Wi-Fi and Bluetooth as they are on the same frequencies as the MA.  Cell network and data should be fine though?  I wondered if the GPS ephemeris data might be downloaded from the net via the app to the MA in order to speed up acquisition.  If not, other than live streaming there is no need for mobile network data and that would stop annoying facebook / WhatsApp messages interfering with my concentration!

I always leave cellular data on to cache my maps in hybrid during flight - it causes no interference so leave airplane mode on or it will turn of the cellular.
Ensure WiFi and Bluetooth are off and that you have no other apps running in the background.

A CW Posted at 2018-5-11 04:35
Metal is a conductor. That means it absorbs electricity. As radio waves are electromagnetic, metal also absorbs those. It is the conductive capacity of copper wire that makes the receiving antenna capture the incoming radio signal. The same is true for other metal objects, although those other objects are not connected to any mechanism to interpret the radio waves into data or sound, and so the waves just stop there. Stand on top of a bunker with reinforced metal concrete and it WILL affect the signal. That is why DJI themselves and every credible pilot on this forum advise never to take off near metal structures - which will also impact on the performance of the compass. It may also explain why I can fly over a mile with my MA not near any metal objects yet the OP can't get further than 550 metres...

I understand not taking off near metal structures because of compass interference but I find it hard to believe that somehow that bunker under his feet is transmitting on the 2.4ghz band and radiating signals that are interfering with his comms. I fly my Mavic in a quarry that only has metal machines going round and a few 1000 kva sub stations and the metal has never interfered with comms, compass yes, comms no.

You also failed to mention that you can "pre download" your flight area before you go out and safely enable Airplane mode without it interfering with you offline map download.

Kevjones1959 Posted at 2018-5-11 04:55
I understand not taking off near metal structures because of compass interference but I find it hard to believe that somehow that bunker under his feet is transmitting on the 2.4ghz band and radiating signals that are interfering with his comms. I fly my Mavic in a quarry that only has metal machines going round and a few 1000 kva sub stations and the metal has never interfered with comms, compass yes, comms no.

You also failed to mention that you can "pre download" your flight area before you go out and safely enable Airplane mode without it interfering with you offline map download.

I didn't fail to mention it as it is not required if you are using a device with cellular data. You do not need to turn off airplane mode at all. Just WiFi and Bluetooth. I have reached maximum range with all seven of my DJI drones over the years and ALWAYS fly with cellular data on to save me the hassle of caching maps.

Metal objects will primarily impact on the compass and GPS. If they are also electromagnetic they will impact on the radio signal - who knows what it in that bunker. The fact is that the OP is getting 25% of what his drone is capable of. So it is important that he understands how to establish optimal environmental conditions to maximise the performance of his drone which is what this thread is about. Not standing on top of a reinforced bunker should be his first step don't you think? For you to advise that it makes no difference is a little worrying TBH.

Actually I'm getting 110% of the range it's spec'd to in 5.8GHz CE mode, the manual says 500m range.  I have doubts about the auto 2.4/5.8GHz channel switching and I doubt any reinforced concrete metal would impact that.  I will try the exact thing again with it forced to 2.4GHz.  This place is a 5 minute cycle from where I live so easy to carry out some controlled tests there.

Thanks for the suggestions.  First thing is to reproduce what I did but with 2.4GHz.  Then to make another flight taking off away from the bunker if I can find some short grass.

AndrewUK Posted at 2018-5-11 06:03
Actually I'm getting 110% of the range it's spec'd to in 5.8GHz CE mode, the manual says 500m range.  I have doubts about the auto 2.4/5.8GHz channel switching and I doubt any reinforced concrete metal would impact that.  I will try the exact thing again with it forced to 2.4GHz.  This place is a 5 minute cycle from where I live so easy to carry out some controlled tests there.

Thanks for the suggestions.  First thing is to reproduce what I did but with 2.4GHz.  Then to make another flight taking off away from the bunker if I can find some short grass.

Well good luck, think you have enough info now to work with. Hope you get the same distances I am soon enough.

AndrewUK Posted at 2018-5-11 03:43
Good tips didn't think of that.  At least turn off phone Wi-Fi and Bluetooth as they are on the same frequencies as the MA.  Cell network and data should be fine though?  I wondered if the GPS ephemeris data might be downloaded from the net via the app to the MA in order to speed up acquisition.  If not, other than live streaming there is no need for mobile network data and that would stop annoying facebook / WhatsApp messages interfering with my concentration!

I use a dedicated phone for my mavic air which doesn't even contain a sim card, so no issues with airplane mode.  I have downloaded google maps "offline maps" for most of the UK, so no issue with maps either.  I even cached satellite images in maps before leaving home over wifi to see if that worked too, and it does if you prefer those.

It does not auto switch between 2.4ghz and 5.8ghz for me you have to manually select to change it,mine is always on 2.4ghz.

For now the longest distance i have flown is 700 meters but it can go futher on 2.4ghz, In the video below i had already used up most of my battery but had to head back, This is on the new firmware.