I have several P3's (don't ask). Some have been 'grey imports' , one has been a UK sourced machine and one shipped by DJI directly to the UK. There is no difference in output when measured at the Tx output connector when the transmitter is on the bench with the aircraft powered on and off. So I am really puzzled at how the regulation of the Tx power occurs. Clearly there must be a difference in output between FCC /EEA as it would be inaccurate to claim differences and ship the same unit worldwide - how this happens in practice is a real mystery. Not sure if the aircraft has anything to do with it when in flight? I wonder if the Tx power increases as signal strength from aircraft drops off. I have also tested x2 Inspire Tx which were sourced from Hong Kong and they are pretty much the same. The theory that your Tablet device may dictate the Tx power may have some merit - proving it is a lot harder.
CEE/FCC switch found ?
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only evidence is that DJI already made similar approach when you want to customize video stream channel & quality selection - available only for US, based on regional selection in tablet/phone.
If the GPS way to set FCC/CE mode would be easy to do, why they choose different approach for video FPV transmission ? I think they do that to obey same rules, there are some channels forbiden in EU
anyway, this whole thread is speculation, as I want to increase my range of FPV, I need custom setting for video TX, so I fly my phone set to English US setting
If the GPS way to set FCC/CE mode would be easy to do, why they choose different approach for video FPV transmission ? I think they do that to obey same rules, there are some channels forbiden in EU
anyway, this whole thread is speculation, as I want to increase my range of FPV, I need custom setting for video TX, so I fly my phone set to English US setting
As a former SE for Verizon, I used to sell Fleet Management software to the military and thought I'd share that creating a geofence around anything (a city block, an airport, a state or a continent) is as simple as drawing a polygon on a map. The software takes care of all the lat/long coordinates. It takes literally 90 seconds to create a new geofence and define rules around it.
I have absolutely no idea if DJI uses them to manage settings, but thought I'd share how simple it would be if they chose to do so.
I have absolutely no idea if DJI uses them to manage settings, but thought I'd share how simple it would be if they chose to do so.
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Very odd as I have a US import and the transmitter clearly states on the back it has CE certification....
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Everybody will have Japanese certification also (like "T" mark, or 〒 in circle). That's very strict to take...
mine has fcc all so. I would love to know the truth on this setting i really would. All the old school members will remember how i delved into this subject a long time ago. LOL
Hi mohan your test results are interesting and like you say the tablet device may play a part like said in the start of this thread. Just curious now more than anything. I was worried about range for my pre ordered CE model when this subject first came about and dji had not even started shipping them out the factory when this subject hit the forum. Since then tho we all know even the CE models are good for distance with only battery really being the problem, that said im sure many would like a little more punch through the trees ect ect if they could.
Hi mohan your test results are interesting and like you say the tablet device may play a part like said in the start of this thread. Just curious now more than anything. I was worried about range for my pre ordered CE model when this subject first came about and dji had not even started shipping them out the factory when this subject hit the forum. Since then tho we all know even the CE models are good for distance with only battery really being the problem, that said im sure many would like a little more punch through the trees ect ect if they could.
Lee
I tried to change my location on the ipad but it didn't seem to make any difference...
Going to keep on trying..
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Sorry if my reply was not clear - I was able to change the localisation and then the custom channels but the output didn't jump upto 100mw. Need to test more to ascertain.
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Thanks for testing that! BTW could you happen to fly to the US and bring that signal meter to see if updated GPS coordinates switch output? Thanks....
ok, how are you measuring the OP power ?
I did the mod on tx for external antennas and plugged the output into a ImmersionRC RF meter
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I would love to..
This was the device I used..
http://modelradioworkshop.co.uk/shop/specialised-items/deluxe-2-4g-r-f-output-checker/
DG
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N017RW
Premium Pilot
The device linked is not a power meter. It's a field strength meter.
The FCC dB limits are measured as conducted power into a 50ohm load.
Thus the measurement device must be connected to the antenna port to perform this.
The radio's output is ERP which is the conducted power + antenna gain.
According to the P3 controller's FCC Authorization Grant the Tx submitted for test has a conducted power of 16dBm and an antenna gain of 3.5dB.
Thus the ERP of the U.S. (FCC) P3 Tx is 19.5dB. Not quite 100mW.
The FCC dB limits are measured as conducted power into a 50ohm load.
Thus the measurement device must be connected to the antenna port to perform this.
The radio's output is ERP which is the conducted power + antenna gain.
According to the P3 controller's FCC Authorization Grant the Tx submitted for test has a conducted power of 16dBm and an antenna gain of 3.5dB.
Thus the ERP of the U.S. (FCC) P3 Tx is 19.5dB. Not quite 100mW.
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The question was to mohan who indicated in an earlier reply he had a power meter attached to his controller. .
DG
