CEE/FCC switch found ?

dronebandit · Jul 29, 2015

in other thread guys found out that video transmission channel /quality is customizable/fixed depending on regional/language setting in your Android/IOS phone. When I switch my phone from local language to English (US) , I can select custom channels and bitrate for FPV video. Could it be that those also influence FCC/CE TX power output ? or 2 HW versions of TX more probable ? which I do not belieive, as software dependent switch would be easier and less expensive than managing logistics and parts for assembly of 2 HW versions.
Also on P2V+ there was 1HW and (hw/sw) switch button.

correction - title should say CE, not CEE

Meta4 · Jul 29, 2015

According to DJI people there is one version and it switches based on GPS location.

robinb · Jul 29, 2015

dronebandit said:
in other thread guys found out that video transmission channel /quality is customizable/fixed depending on regional/language setting in your Android/IOS phone. When I switch my phone from local language to English (US) , I can select custom channels and bitrate for FPV video. Could it be that those also influence FCC/CE TX power output ? or 2 HW versions of TX more probable ? which I do not belieive, as software dependent switch would be easier and less expensive than managing logistics and parts for assembly of 2 HW versions.
Also on P2V+ there was 1HW and (hw/sw) switch button.

correction - title should say CE, not CEE

yes i was wondering the same.

i don't think they could store all the gps locations, eu, usa, asia, etc etc

dronebandit · Jul 29, 2015

yes, exactly, I do not believe they put somewhere inside huge database of GPS locations just in order to set CE/FCC. They got already problems to capture reliably non fly zones (i.e London Heathrow etc.)

which are far more important
Setting by regional/language setting is easy to do.
Pure speculation though, no evidence

Meta4 · Jul 29, 2015

No need for a huge database. It's a simple matter of Europe = CEE and everything else = FCC.

taroh · Jul 29, 2015

Switched by GPS location...? Doubtful.

What if one use inside house?
And (it's function of TX, not aircraft, I think) what if Pad don't have GPSr?

F6Rider · Jul 29, 2015

They don't need to specify every location, just a range of GPS coordinates covering the area intended.

F6Rider · Jul 29, 2015

taroh said:
Switched by GPS location...? Doubtful.
What if one use inside house?
And (it's function of TX, not aircraft, I think) what if Pad don't have GPSr?

We are talking about the GPS receiver in the P3, not your iPad, and if you're indoors it will default to the last registered GPS location. What? you're going to register a location then pack up and fly to London to fly indoors again?

taroh · Jul 29, 2015

F6Rider said:
We are talking about the GPS receiver in the P3, not your iPad, and if you're indoors it will default to the last registered GPS location. What? you're going to register a location then pack up and fly to London to fly indoors again?

Original topic was about TX power. I know 2.4GHz communication is bidirectional, however.
And it's natural that P3 is tested in Shenzheng, packed and sent to London, and first flight is indoor... It's very slight problem, but does CE test & certificate institute authenticates eqips with such a power control? That's my question.

edit & answer to my own question - I surveyed how to get CE mark... it's self test & declaration, not authenticated by any institute. Sorry.

If DJI has certain technical argument that the device can control the power by GPS location, they can display CE mark by themselves.

F6Rider · Jul 29, 2015

taroh said:
Original topic was about TX power. I know 2.4GHz communication is bidirectional, however.
And it's natural that P3 is tested in Shenzheng, packed and sent to London, and first flight is indoor... It's very slight problem, but does EC test & certificate institute authenticates eqips with such a power control? That's my question.

You missed my point, the Tx power is set by GPS location according to DJI. The controller talks to the P3, which has the GPS receiver, and sets the Tx power accordingly. There is no need for a huge location database as all DJI needs is to code in a range of GPS Lon/Lat (north/south/east/west) locations to set the allowed power, not hard to do at all. And, you didn't ask that question, to which I can say i don't know.

robinb · Jul 29, 2015

EU is not a square with 4 corners, to define EU would take thousands of coordinates.

rigor · Jul 29, 2015

do you think it could go on your ip address if you download the firmware in the uk it would be ce and if you download from the usa it would be fcc that wouldnt be hard to do

robinb · Jul 29, 2015

rigor said:
do you think it could go on your ip address if you download the firmware in the uk it would be ce and if you download from the usa it would be fcc that wouldnt be hard to do

no

rigor · Jul 29, 2015

why not i have always thought thats how it would work i downloaded mine with a vpn from the us and i got it out well over a mile in the uk with full signal strengh but im no expert

robinb · Jul 29, 2015

nahh

I get over a mile and i downloaded mine in EU.

rigor · Jul 29, 2015

ok so i wasted my time downloading everything from the usa ha ha

J.James · Jul 29, 2015

Switched by GPS location...? Doubtful.
What if one use inside house?

Now thats got to be one big house to worry if you are in ce of fcc power output and worried about needing more range when flying indoors.

leekiya · Jul 29, 2015

Dji do not claim they are set by GPS location, it is the forum techs who have told us this. If you email DJI they say they are factory set according to there shipping destination. The other week a company on ebay in the uk were selling the pros for £899 and i was tempted to get another one so contacted dji regarding this company and if there would be a proper warranty if i purchased one from them. They replied there would be but this company in the uk were importing them from USA, so flying the imported version would be breaking the law in the uk as it would be set to FCC and not CE which it should be for flying in the uk, so who knows.

N017RW · Jul 29, 2015

I found when researching this a while back that the U.S. FCC approval grant for the Tx submitted for testing indicates a conducted output of 16dBm (40mW).
It further indicates it is equipped with an antenna with 3.5dBi gain (only one transmits). This would bring the ERP up to about 19.5dBm or ~90mW.

It MAY be that if it is true about region specific hardware that the antenna is different for CE i.e. unity gain type.

Just a thought.

Glimo · Jul 29, 2015

I bought a P3 having it shipped here from the US. Using a signal strength meter on the Controller, before and after I homed the Quad to any UK home point, I didn't get any difference in field strength.

I haven't checked the output by changing the default language but I will now!

Edit - I just tried testing with the Ipad 2 region set back to US (and rebooted) with no change to the Signal Strength between either..

DG