Advanced GPS P3 Advanced HELP PLEASE!!

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Am completely confused.
Basically DJI app says I have full satellites and when I go higher than optical sensors can locate the ground I get atti mode on screen and GPS lock failure despite having 11 plus satellites on the app. See above link and screen shot attached.
This drone has never had a crash and is basically new as I've only flown it once or twice before to test it.
Recalibration of imu controller compass gimbal and latest firmware...

HELP PLEASE.
what I don't get is why I'm losing GPS lock with full satellite cover in p mode?
Totally confused.



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Am completely confused.
Basically DJI app says I have full satellites and when I go higher than optical sensors can locate the ground I get atti mode on screen and GPS lock failure despite having 11 plus satellites on the app. See above link and screen shot attached.
This drone has never had a crash and is basically new as I've only flown it once or twice before to test it.
To have GPS mysteriously drop when your Phantom climbs doesn't make any sense.
As the warning says ... Abnormal compass etc etc....
The compass is the most likely suspect and one you need to eliminate first because GPS errors are very rare.

You need to look at where you've calibrated the compass.
When you recalibrated the compass was there any steel or electric cables nearby?
A car, structural steel, power cables or (most commonly) reinforced concrete?

If you calibrate your compass where the earth's normal magnetic field is distorted by these, when you fly away from their magnetic influence the compass now detects an abnormal magnetic field.
That is ... one that it has not been calibrated for.
And when the Phantom has conflicting data because the compass data doesn't match the GPS data, it stops reading GPS and switches your Phantom to atti mode.
 
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I had a the same problem in three locations. My folks back yard where I've flown a lot and my own backyard plus an empty field near my house. All places I've flown before and calibrated before. I even took my pocket charge out!
I'm totally confused. The compass calibration was ok every time I tried. I did the calibration before each attempt.
Thanks for the reply. I have hooked up to my PC and found no hardware problem. I used my iPhone my s7 and my iPad mini 2. Always the same results. No metal for a hundred yards including underground wires. ?????
Thanks for replying.


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Maybe I'll switch out the compass ?


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yep
easy 10 to 20 dollar fix

clearly the gps is receiving signal
that points to compass being the suspect.

and we hear for more bad compass reports than bad gps
so the odds are for the compass being bad

good luck and have fun flying!
 
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Cheers for that. I'll post on how it works out. I'm going to drop it into my local DJI dealer for repair. It's only a few months old with no flying time so hopefully it'll be warranty work.


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The bird thinks she has covered 5,945 km in 26 seconds..... I'm gonna say you have bigger issues than a dodgy compass.
 
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Never spotted that... Maybe GPS is not working? I will find out soon, leaving it into DJI dealer here in Dublin, Ireland, they are really good guys.
 
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Never spotted that... Maybe GPS is not working? I will find out soon, leaving it into DJI dealer here in Dublin, Ireland, they are really good guys.
gps and compass work together to compile the flight data in the FC.
if compass is bad then all else can reflect incorrect data and readings.
thus the chance of flyway-- it got no idea where it or where it going
 
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Definitely bad compass. This is why its on ATTI mode.
Whats the MOD compass reading on the Sensors page in the GO APP??
 
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The compass reading is actually normal and I don't get a calibrate compass warning before take off. It calibrated normally too, but if you are asking if there's wild variations the answer is no. I think is not a compass either. I spoke to Copter Shop this AM in Dublin Ireland and Damien there thinks it's a faulty firmware issue. Apparently it can upload firmware and be corrupt but tell you it was a success. Am going to reload old firmware and try. It'll be a few days before I have a chance as I'm abroad for a while but I will keep you posted. Thanks so much for the help!!
Mukesh


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I downgraded the firmware then reinstalled the latest firmware again. Have still got weird readings on the DJI app but not in litchi !!
Anyway full gps lock and can't see any problems on healthy drones. Not trusting DJI app very much to be honest. Was windy and took it to 57 feet with no issues. Am in a crowded neighbourhood so I didn't have the chance to stretch its legs.
Will now be able to give it to my brother who's a novice but wants it to film his dogs. I'm happy he won't crash unless he's being an idiot I think.....


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HealthyDrones.com - Innovative flight data analysis that matters
I downgraded the firmware then reinstalled the latest firmware again. Have still got weird readings on the DJI app but not in litchi !!
Anyway full gps lock and can't see any problems on healthy drones. Not trusting DJI app very much to be honest. Was windy and took it to 57 feet with no issues. Am in a crowded neighbourhood so I didn't have the chance to stretch its legs.
Will now be able to give it to my brother who's a novice but wants it to film his dogs. I'm happy he won't crash unless he's being an idiot I think.....


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The reason you don't see these errors in the Litchi app is that the Litchi doesn't report these types of errors. The DJI Go App is the most comprehensive of all the tablet apps. If you attached the .txt from the flight we cold take a look. It has to be the .txt from the flight you referenced in the first post. As far as I can tell the HealthDrones links you have provided are from other flights.
 
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The reason you don't see these errors in the Litchi app is that the Litchi doesn't report these types of errors. The DJI Go App is the most comprehensive of all the tablet apps. If you attached the .txt from the flight we cold take a look. It has to be the .txt from the flight you referenced in the first post. As far as I can tell the HealthDrones links you have provided are from other flights.
Thanks for the advice. I'll try and upload the text files later. I appreciate the expertise as I don't want to give my brother a dud. Thanks


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The reason you don't see these errors in the Litchi app is that the Litchi doesn't report these types of errors. The DJI Go App is the most comprehensive of all the tablet apps. If you attached the .txt from the flight we cold take a look. It has to be the .txt from the flight you referenced in the first post. As far as I can tell the HealthDrones links you have provided are from other flights.
Here's a flight log before I did the firmware again. I hope I've done it right?
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