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Best of the best site for compass calibration

Discussion in 'Pro/Adv Discussion' started by phantomi, May 14, 2016.

  1. phantomi

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    Only wondering what are the best place to do a compass calibration. Over earth, sand, concrete, inside or outside, high or low, open or close? Just wondering.
     
  2. msinger

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    It's best to do it outside away from anything metallic.
     
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  3. phantomi

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    I'm going to do a new one in a sandlot near my house. I'm flying with one done over concrete and had to move several times until get it. There is always iron under that don't let you do a cc.
     
  4. phantomi

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    It's best to rotate the bird in it's own axis or do a circumference with it?
     
  5. msinger

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    I hold the bird steady and turn my body. While both methods will accomplish the same thing, you most likely won't accidentally drop your bird when turning your body.
     
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  6. Meta4

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    Concrete is a no-no.
    It's usually full of steel reinforcing
     
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  7. RedHotPoker

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    Just stay away from any ferrous metal and electrical interference.
    That's often accomplished best outdoors and in an open clearing.
    Once you do a good compass calibration, you shouldn't have to worry about it, unless you move a couple hundred kilometers away from the original spot. Even then, it may not be necessary.
    I hold the drone in front-me and turn on my heels, for both sides.
    Yeah, most concrete has steel rebar reinforcing rods.

    RedHotPoker
     
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  8. vipercubic

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    I had compass error in both my last flights (midflight). I think it's because I calibrated with my mobile and watch really close. When this error pops up it's better to switch to atti or wait for a good signal?

    Sent from my Nexus 7 using Tapatalk
     
  9. Mark The Droner

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    Last fall I thought I was pretty smart calibrating my P2V in the dead center middle of a big open playing field at the nearby rec center. Nope. It was a bad calibration. Apparently the field has a steel underlayer of some sort? I don't know.

    IMO, the best of the best site for compass calibration is the last site you used successfully. In my case, it's my back property.
     
  10. p3pflyer

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    Are there any specs on how far away from your vehicle you should be to avoid it's effect?
     
  11. msinger

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    No. But, about 10 feet away should be plenty.
     
  12. ghostpeak

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    Having operated the P2V Plus for quite a while, I got into the habit of only calibrating the compass in the following circumstances:
    - I had travelled more than 100 miles.
    - After a FW update.
    - If the app/craft told me too and I had ruled out interference from an external source, i.e.; fences, concrete, wiring, cars, watches, phones, metal of the ferrous kind, volcanoes and zombies!

    In the 1.5 years i have operated her, never had a compass related issue, even took off from a speedboat!

    My mantra, probably stolen from someone on here is 'If it aint broke, don't fix it'!

    When I originally started out I did it before every flight, but when you consider the risk you introduce into the system when you are constantly recalibrating it, it makes sense to do it once and only redo it when something significant changes!

    I appreciate that this is a controversial topic, this is just an anecdote of my experiences.
     
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  13. FrequentFlyer

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    Everyone listen close...
    It's the voice of reason and sensibility.
    Thanks Ghost.


    Sent from my iPhone using PhantomPilots mobile app
     
  14. N017RW

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    Good advice and in my case I have calibrated my P2 3 times since May '14 and not once in the last 1-1.5 years.
    Since the last cal I have traveled 600 miles without a cal upon arrival or return.
     
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  15. kenjancef

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    Maybe irrigation lines in the field? I have a filed right across the street from my house, and they just recently installed irrigation, but I have no clue if the lines are PVC or metal, no clue about that sort of thing. But it'd make sense, right? I calibrated mine in that field and it was fine...
     
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  16. N017RW

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    Never done that.

    First cal I did was out-of-the-box.

    Second cal was to confirm I knew what to expect.

    Third cal was after replacing the control system with a Futaba T10J.
    Initially I did not recal after the receiver swap on purpose to see the effect.
    I noticed immediately it did no fly straight (as was predicted here by many).
    Once I re-caled, all has been fine for the last 1-1.5 years.

    The primary purpose of the cal is to compensate for distortions created by on-board metals (confirmed by my experiment before 3rd cal mentioned above). But it does this in reference to the ambient magnet field, etc. so there is some dependency on the local field(s) but to a lesser degree than on-board materials. This is why it is mandatory to re-cal after adding, removing, or relocating equip. or accessories on the aircraft itself.
     
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  17. CCDD

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    Can someone logically explain how compass errors can occur after take off after successfully completing a compass calibration just prior to?
     
  18. Fplvert

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    I've had one that I attributed to iron deposits in a sand lot. I could get the P3 to take off, but about 30-50' away I'd get a compass error. Switched to ATTI and caught the bird twice. The third time I moved away from the sand lot and recalibrated with no problem.

    The only other time it behaved in this way was indoors on concrete. In my opinion, the P3's compass is more sensitive to compass deviation in the environment.
     
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  19. MikeyOnline

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    One thing I always do is place the controller and mobile device about 20 feet from the AC when I'm calibrating the compass. Once you start the process on the screen, there's no need to come back to the device and risk EM interference. Just walk over to the AC, pick it up, do the flat 360 until you see green lights, then turn it and do the face down 360 until the green lights start to blink. That way your RC/phone won't interfere.

    Mike
     
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  20. CCDD

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    That's great advice Mike!!