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Spark locked in US mode while I'm in EU
4480 23 2017-8-25
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Matioupi
First Officer
Flight distance : 922569 ft
France
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Hello,

following this thread http://forum.dji.com/thread-110106-1-1.html where I was wondering why I'm overshooting the advertised ranges, I've been doing a few experiments and low level checks of WiFi things.

From those investigations, it seems that my Spark is locked in FCC / US mode (while I'm in EU).

In order to check what is going on, I've been using a custom Android box (cf. http://forum.dji.com/thread-108556-1-1.html) based on an Odroid XU4, together with a dual band wifi adapter (this model to be exact : https://www.alfa.com.tw/products_show.php?pc=67&ps=230)

I've build a modified version of android kernel which is correctly implementing all the regdomain stuff.
I've been validating this point with my home Synology RT2600ac router.
This router allow to set the regdomain to whichever country the user likes to, with a warning about possible legal implications.
This way, I've been able to check that the command "iw reg get" executed on the android box correctly reflects the regulatory domains which is set on the router and broacasted by him.

That done, I connected to the Spark RC and saw that it is broadcasting "US" regulatory domain.
I've been checking that this does not change when the Spark is turned on first and wait until it has GPS position : even when turning RC on after Spark gets a lot of GPS, it still broadcast "US" regdom.

After finding, I've been double checking  (with the same iw reg get command) from a linux laptop (dual band Wifi) with an up to date Ubuntu 16.04 distro (unmodified) and results are the same : RC is always using "US" regdom.

If from those experiments, other users could test the regdom their system goes to, that would be nice !

At least, this explains why I'm having better ranges than advertised...

2017-8-25
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Spaners
lvl.3
Flight distance : 1542 ft
United Kingdom
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You lucky sod, wish mine was on fcc setup
you obviously know a thing or two about these things
Do you know if it is possible to change the region on a nexus 7 (2nd gen) DJI recommend these as being compatible, the problem is the EU version can not see the required 5G8 channels where as a US version can.
I also understand that the Spark hack involves a change to the software that makes the spark iggnor the location data from your mobile device hence defaulting to the higher output power allowed under fcc rules. Prehapps your mobile device region code is set to USA (or another region that dose not require output to be attenuated) and thus the spark will transmit at full power ?
2017-8-25
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Matioupi
First Officer
Flight distance : 922569 ft
France
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Spaners Posted at 2017-8-25 10:35
You lucky sod, wish mine was on fcc setup
you obviously know a thing or two about these things
Do you know if it is possible to change the region on a nexus 7 (2nd gen) DJI recommend these as being compatible, the problem is the EU version can not see the required 5G8 channels where as a US version can.

Hello,

first I did not knew that much before buying the Spark, I'm in the learning curve (I admint I have quite good tech background that makes it easier)

second, I did not hack anything on my Spark system at any level. It is a real question to DJI mods why I'm locked in US mode... Even without OTG. The only exotic setup is at the "phone" device level were I've been trying a custom android device, but running the full official DJI GO 4 app.

Last thing about your questino : as far as I understand it from what I can see on my devices, the regulatory domain for a WifI link seems to be driven by the access point (AP which in our case is RC for those with RC and it must be Spark when no RC is at play). At least is what my tests shows.

The router / access point broadcasts its regulatory domain and once the client (phone, bird) is connected, The client sticks to those rules according to its internal regulatory database.

My guess (only hypothesis) is that some Android phones / OS versions / kernels get confused when they were first connected to some kind of regdom (e.g. FR or EU) and then told to  go to US. It could even be that the cellular layer is sayong something else wich must end in a big mess...
Maybe some phone are using a too old database too (e.g. in Europe, the 5 GHz channels used by DJI where allowed only since 2014 and many kernel stacks are 3.10.xxx and those layers may not have been fully updated by developpers. They may even have purposely disabled those channels for compatibility when the phone is used as an access point)

As far as I can say, I had better results with starting the device with WifI OFF and everything else in Airplane mode, no other network recorded to prevent auto connect vefore connecting to RC or Spark, and turning Wifi On after device booted up.

I'm only using devices without cellular so far (dedicated to the Spark)
2017-8-25
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Spaners
lvl.3
Flight distance : 1542 ft
United Kingdom
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I wasn't suggesting that you had tried to hack the dji software, only that the hack I read about told the spark it was in an fcc region no mater what the mobile device told it
I think the reason will be in your mobile device rather than in the spark
Take it firmware updates have not made a difference which would sugest the spark is getting its regional position from the mobile device and not from the GPS ?
Definatly an interesting post
2017-8-25
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Spaners
lvl.3
Flight distance : 1542 ft
United Kingdom
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PS your comment about access points makes a lot of sence as to why so many EU android devices are not able to connect on the SRD channels
2017-8-25
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Matioupi
First Officer
Flight distance : 922569 ft
France
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Spaners Posted at 2017-8-25 11:06
I wasn't suggesting that you had tried to hack the dji software, only that the hack I read about told the spark it was in an fcc region no mater what the mobile device told it
I think the reason will be in your mobile device rather than in the spark
Take it firmware updates have not made a difference which would sugest the spark is getting its regional position from the mobile device and not from the GPS ?

At least in cases where :

- the phone/tablet do not have cellular
and
- the phone/tablet do not have GPS / position
and
- the phone/tablet do not have internet access upon DJI GO 4 start

then it seems that RC sticks to "FCC / US" mode and is not using the Spark bird GPS info if it has some.

I have not tested device - Spark connexions (no RC)
2017-8-25
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Montfrooij
Captain
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Netherlands
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This is a strange case indeed as the Spark does have GPS, so it should know where it is.
Maybe this setting is mobile driven since that is what's different in your case.
2017-8-25
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Spaners
lvl.3
Flight distance : 1542 ft
United Kingdom
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mabe doing a reset on the spark, then connecting with a mobile device with wifi off and no gsm connection and no gps (indoors) would result in it defaulting to an fcc regional setting
don't know how you would test that, I'm not that techie
2017-8-25
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realstreetuk
Second Officer
Flight distance : 7966 ft
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United Kingdom
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i seem to get really good range over expected, how do i check if mine is also locked to fcc?
2017-8-25
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lafoto
Second Officer
Flight distance : 1402680 ft
Portugal
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I WOULD LOVE TO HAVE MY SPARK LOCKED IN US mode!...
2017-8-25
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Matioupi
First Officer
Flight distance : 922569 ft
France
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realstreetuk Posted at 2017-8-25 12:31
i seem to get really good range over expected, how do i check if mine is also locked to fcc?

Easiest way I can think is to take a PC machine with a dual band wifi adapter and run it under a mainstream Linux distribution. I suggest to use Ubuntu Mate 16.04

There are tons of tutorial around to explain how you can download and prepare a USB boot stick or external HD boot drive. That way, you'll boot off the Linux without installing it over you Windows install if you just want to try.

After doing so and booted under linux, start you Spark RC. Go to the wireless network widget on Linux desktop and connect to it (password 123412434) as if it was a regular router network.

Once done, open a terminal windows and type command "iw reg get"

that will display the 2 letter code of the country regulation mode it had stick to.

edit :
don't do that from a virtual machine as it will only reflect a simulated wifi layer if it even works. You need to actually do a real boot on a linux kernel that drives the wifi adapter.
2017-8-25
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Jvenaas
lvl.1
Flight distance : 381309 ft
Norway
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I can confirm i also got US country code, even while connected to my iphone and mobile data enabled.
2017-8-26
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Matioupi
First Officer
Flight distance : 922569 ft
France
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Jvenaas Posted at 2017-8-26 01:04
I can confirm i also got US country code, even while connected to my iphone and mobile data enabled.

Good to know I'm not alone :-)
I guess you don't have range/disconnection issues with your Spark ? (I'm really not complaining with respect to this : OTG is rock solid and I'be been flying 3 batteries in full WiFi mode this morning and had no issue at all)
2017-8-26
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Jvenaas
lvl.1
Flight distance : 381309 ft
Norway
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my biggest issue is lag, but had a flight at 1700m in 2.4 yesterday with wifi
2017-8-26
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Matioupi
First Officer
Flight distance : 922569 ft
France
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Jvenaas Posted at 2017-8-26 07:34
my biggest issue is lag, but had a flight at 1700m in 2.4 yesterday with wifi

This is quite similar here, I've not reached 1700 m. This morning I reached 1200 m in full Wifi (no OTG) and 2.4GHz but lag was quite high.

From a very subjective point of view, I would say that OTG + 5.8GHz do give the better result but still quite high. Maybe they reduced the CPU load of some video straming functions in last firmware to prevent overheat and this lead to high lags as I believe it was a bit better before 1.00.600.
2017-8-26
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Matioupi
First Officer
Flight distance : 922569 ft
France
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Jvenaas Posted at 2017-8-26 07:34
my biggest issue is lag, but had a flight at 1700m in 2.4 yesterday with wifi

I just flew at over 1500m in OTG 2.4GHz (changing the frequency in non OTG mode first).
2017-8-27
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Matioupi
First Officer
Flight distance : 922569 ft
France
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RE: Spark locked in US mode while i'm in EU ?

just modiifyed the thread title in case it can lead to some mod reaction...

2017-8-27
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Lian82
Second Officer
Flight distance : 796775 ft
Italy
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The FCC mode is noted by the 2.4ghz wifi channels

FCC 11 channels
CE 13 channels ..

Check .. on my ipad air 2 no 3g, i'm always in FCC.

In my areas arriving at 240mt 2.4ghz and 150mt in 5.8ghz(CE MODE), I now (FCC MODE) both come to +1.6km (still to be tested in very open spaces)

My friend arrived at 2.3km 2.4ghz
2017-8-27
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Matioupi
First Officer
Flight distance : 922569 ft
France
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How did you changed from CE to FCC mode ?
2017-8-27
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ToyCarCollector
lvl.3
Flight distance : 202126 ft
United States
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So if I go to France and Germany can I fly my USA spark?  
2017-8-27
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Matioupi
First Officer
Flight distance : 922569 ft
France
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Most probably you can. If your RC + Spark has the CE label on it, then you are Ok to bring the device here.

Maybe you'll be outlaw about regdomain if the system stays in FCC mode (like mine, without doing any hacking of any kind if you don't consider OTG hacking), but after digging a little into this technico-administrative hell, my guess is that I don't see how any kind of law enforcment could happen about this...
Last year I call field police because I found an old bomb shell (was empty in the end) in my backyard after doing some light earthwork. They came as a first stage to check it was not a piece of tube and trigger escalated intervention. They had a paper file to fill where they had to measure length and diameter + take a picture. Their camera battery was out and they did not took a tape... I provided one and they did measured circonference... (which I let them do because that would lead to a pi time bigger shell and hopped it would trigger a faster intervention.
How could they check the regdom of some WiFi stuff ?
Of course they are probably specialized RF team in the police or other national agencies, but hopefully they are busy tracking illegal high power emitters or GPS jammers around airports...
2017-8-27
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Matioupi
First Officer
Flight distance : 922569 ft
France
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A good tech source (quicly turns very technical...)  of information about wireless is :

https://wireless.wiki.kernel.org/

you'll maybe like :

https://wireless.wiki.kernel.org/en/users/documentation/faq

on of the last questions of the faq is about regdoms and it seems that some Wifi cared have regdom burned in while other are more configurable...

There is also a link to the latest version of regdom database :

https://git.kernel.org/pub/scm/l ... tree/db.txt?id=HEAD

Where you can check what Linux guys have understood about rules for you country...

My Synology router for example features a "European union" setting but the db.txt file above do not have such an EU code, as EU dictates rules that must then be translated into national regulations (I told you... hell)
2017-8-27
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DJI Susan
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I have replied you in this post: http://forum.dji.com/thread-110106-1-1.html
2017-9-3
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Matioupi
First Officer
Flight distance : 922569 ft
France
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I saw your reply, but I'm not flying with OTG anymore... and i'm making the same observations as before so your reply does not help that much.
I'm not using OTG and RC still broadcast "US" model regulatory domain (checked with several different Wifi analysis tools)

By the way, do you have updates on the "EU" wifi bug status ? Its been acknowledge several times by some DJI support members but nothing has been addressed yet as far as I know.
2017-9-6
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