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Radar direction off

Discussion in 'Phantom 2 Vision + Discussion' started by rrmccabe, Sep 18, 2014.

  1. rrmccabe

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    Just replaced my Galaxy S4 today with a warranty replacement and took off and noticed the aircraft was heading towards 3:00 on the radar instead of 12:00.

    I ran it out and initiated RTH and it came back right direction so that was OK. Power Cycled everything and same issue.

    I can only assume I need to something to calibrate the compass on the phone?
     
  2. Fplvert

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  3. rrmccabe

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    Thanks. I downloaded GPS status app and looked at compass and it was "about" 90 degrees off similar to my radar. The app had a calibration function so I did that and it appeared to fix it.

    I have not flow the Phantom again to check but I think that was it.

    Little windy here. My test short trip I hit 51mph on the return so I think I will keep it in the hanger for now.
     
  4. itchybeard

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    The compass on my Galaxy Note 3 goes out of whack quite often, but I can calibrate it in seconds using the "figure of eight wave" (I go round the figure of eight about four times).

    http://www.youtube.com/watch?v=sP3d00Hr14o

    I do it before every flight these days.
     
  5. npalen

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    I have the incorrect heading reading on my Samsung TAB4 also. I'm not sure it even has a compass so that is maybe the problem. On the other hand, would the compass reading come from the P2V+ app rather than the device compass? Someone please enlighten my.
    I had the same issue with a Kindle Fire HDX.
     
  6. itchybeard

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    The DJI app uses both the compass on the bird and the compass on your display device, so that it can show the heading of the aircraft and the direction that the pilot is facing as well. I think you are right. Apparently the only sensor on the Galaxy Tab 4 is an accelerometer. So, yes, I would say that is the problem.

    http://www.samsung.com/uk/consumer/mobi ... 18223935:s
     
  7. UKFlyer

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  8. rrmccabe

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    Thanks for link. The calibration last night did fix the radar. I flew it this morning and it was right on.

    Nice to have radar when you are doing this.
     

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  9. denofr

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    "It's a technical toim" ...My Cousin Vinny
     
  10. npalen

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    This is a far fetched question, but wondering if an external compass could be plugged into a tablet that doesn't have an internal compass? I doubt that anything like this exists but I envision a mini-usb device with compass and App.
    It's frustrating as I bought the Samsung Galaxy Tab4 based on feedback that it works great for the P2V+ App and even asked about the radar compass to make sure. I had been using my Kindle Fire HDX with the FC40 because it has great WIFI capability but didn't work so good with my P2V+.
     
  11. rrmccabe

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    In my eyes its not overly critical. You can visually see if thing is off. It basically just aligns your phone with the TX controller. The arrow pointing back always works correctly. Just might not be exactly 12:00 position. Easy to calibrate on the fly.
     
  12. mede8er

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    Last night when I was re-installing my vision app it asked me to do the calibration dance for the app....don't remember ever doing that when I got the bird...but that was some time ago....and yes, my radar is off about 45 degrees....
     
  13. npalen

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    I lost you on this. Can you elaborate? Thanks.
     
  14. tizzl10

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    I have found that if you point your transmitter at the bird then turn it away to say, 3 or 4 o'clock, then back at the bird, then away again, the compass corrects itself..atleast with mine it does. try that.
     
  15. rrmccabe

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    Yes. I guess my feeling is its not overly critical. You could be off a few degrees and its not going to really show up on the radar. How you have your phone clamped in and parallel to the TX could make it off as far.

    I could be wrong but it appears the compass setting in phone only controls the indicator on the tiny little radar. Of course you would not want to +20 degrees off but a small amount probably isn't noticeable.

    Mine worked perfectly when it was 90 degrees off and I could fly it back home. It just wasnt showing from the 12:00 location it really was.

    If there is more to it I am sure someone will elaborate.