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GPS tracker dangerous interference; caused mini crash

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After I lost my first P4 , and no chance to find it (long story..), I decided to use a gps tracker all the time.
I bought a new P4 and attached a TK102 tracker, set it to send sms every 30 seconds. I attached it by adhesive tape to the landing gear.
On the first flight (waypoint programmed flight by Litchi) after manual take off, noticed some drift in the position (about one meter); just ignored it.
Then on the programmed flight between point 2 and 3, the aircraft slowed down and started going up; this was not programmed. The horizontal speed remained at 0-1 m/s and the craft was going up (some 100 meters above the set altitude). I pressed RTH and it came back home, with 3-4 meters error.
I restarted everything and double checked the set altitude for each waypoint, everything was OK.
On the 2nd try, the exact senario was repeated. I canceled the program, lowered the aircraft to the set altitude, and continued the flight by manual control; everything seemed to be ok.
At the end, when I pressed RTH, the aircraft showed a bizarre behavior: it started to land at several meters away from the home point and worst, it was descending too fast!
I realized that it will crash, so I gave a full throttle but it was late. It hit the land so that the landing gear and the gimbal protective cover broke.
Sorry for the long story.....
After repairing everything, I installed the GPS tracker again but this time, I attached it to just one leg of the landing gear so that it wont block the sonar and visual sensors. A test manual flight, and at altitude of about 10 meters DJI Go app alarmed: "maximum altitude has reached" !!!
I was sure that its the tracker signals that interfere with something inside the aircraft causing these errors.
I never used the tracker again. BUT I see here many people are using it without problem.
Can anybody please help about the cause? Had similar experience?
Maybe its because I set the tracker to send message every 30 seconds?
This is important to me because I frequently do programmed mission flights without connection and its likely to fly away again.
 
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Sorry that happened to you. That's actually a reason I am reluctant from getting a detatcable GPS tracker, I'm afraid of radio interference.
 
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Interesting situation...curious to others findings.. have not got a tracker but have been seriously considering it .

Sent from my SM-G935V using PhantomPilots mobile app
 
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GPS trackers can interfere with the operation's of the drone, you would probably be better getting a marco polo tracking system which is not active while the bird is flying and does not work on a gps signal.
When your bird is within a certain distance of the home point and you activate RTH it will simply land where it is so you must make sure there is nothing for it to crash into and that it will not be landing on water
 
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Could it be the area you are flying in? Have you attached it to a different point on your aircraft? Maybe something to do with latest firmware updates
 
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I also got the same TK102 tracker and no issues at all. Could it be a GPS issue?

Neon Euc
 
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I was sure that its the tracker signals that interfere with something inside the aircraft causing these errors.
So you've never flown the craft without the tracker on? Therefore You can't say for certain that the tracker is to blame, you could have had a defective craft from the get go?

Also you say you taped the tracker to the legs. It's possible that the circuit board of the tracker may well have blocked signals to the craft or interfered with the compass sensors by being in such close contact. From what I see these are normally mounted between the legs, not on them.

GPS trackers can interfere with the operation's of the drone
Can you elaborate on this? I can't see how the tracker would interfere with the craft GPS unless it was blocking the antenna. And if it was the text message transmissions at fault then I'd imagine that cell towers (which are pretty strong signal sources) would be bringing down phantoms all over the world.
 
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So you've never flown the craft without the tracker on?
No. I regularly fly without tracker and no issues at all. But the only two times I used it, I saw the problems.
I found that there are two magnets at the back of the tracker (to be attached to something). Maybe these magnets interfere with the compass.
Also i think we should set the tracker not to send sms automatically. If the drone was lost, we call the tracker and if -hopefully- it is somewhere with cellular coverage, it will respond.
I'll check and post the results here ;)
 
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Do you set it to send location automatically at certain intervals? Or what?
I don't let it send me any signals to the phone. It updates every 20 seconds on the map. But I think the problem def would have been the magnet backs. I made that mistake. Didn't take it for a flight but I took the magnet back off and used the plastic. The magnet will interfere with the compass

Neon Euc
 
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But the only two times I used it, I saw the problems.
Got it - wasn't clear from your initial post. I suspect it could be the way you've mounted it on the craft rather than any RF interference - the cellular band is way beyond the transmitter frequency .
 
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Thank you all for the comments.
I am seriously thinking about testing again after weather is fine.
I removed the magnetic back, set the tracker to go in sleep mode untill it is called, and also i have made a nice basket for it by 3d printer.
Will update after test.
 
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been using the tk102 for a while now. Not on all flights, just on dangerous areas. I use a 3d printed holder which position in between the landing gear on the side.

Never experienced any trouble, it works just fine.

Of course if you use the magnet, the compass being in the ''leg'' of the drone it will cause problems. It is very strange that with this configuration you did not get a message telling you to calibrate the compass.
 
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People using trackimo and other tk102 type units will need to upgrade soon. GSM cellular is being retired in the US. ATT just shut theirs down so tmobile is the only major gsm provider left. So the gsm coverage area has really shrunk and rumor has it T-Mobile is looking to shutdown gsm within a year.
 
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Good news :)
Today I tested two flights with GPS tracker, without any problem.
Took off the magnetic back, set the tracker to go in sleep mode (scheduled to wake up after 30 min).
Fixed the tracker by a 3d-printed carriage to the legs on the left side.

The extra weight (58+15 grm) did not noticeably affect the flight time:
(20minutes flight time, 4500 meters distance, more than 9000 meters flight path).
 
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