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Gps lost during flight and while landing

Discussion in 'Phantom 2 Vision + Discussion' started by general01, Jan 20, 2015.

  1. general01

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    Ok I did two successful flights today but had gps issues during both flights

    First flight goes pretty great(8-9 sats) had a small hiccup(lost signal for about 2-3 seconds at 400 feet up only to regain it right after

    So I didn't think much about it till the second flight as the gps signal stayed strong even when I landed(still was getting 7 sats at landing)

    Ok I swap out the battery for the second flight and the bird has a time finding a signal and then the signal is weaker while in flight(only seen 7 at the most at one point in flight)

    Now here is where things get weird

    I could only drop to about 80 feet before losing all gps sats completely(NOT GOOD)

    I had attempted to land three times till I had to pick a alternate landing spot so I wouldn't possiblely crash into a tree
    Needless to say it was a nail biter of a flight and I was nervous during the landing due to no gps at all

    Anyone know as to why it would do like this

    I tried my p2v(non plus) right after and it only seen 5 sats on the ground(normally sees around 6-7 sats on the ground and 8-9 in flight)
    I was recording during both flights(not sure if that had anything to do with it or not)
     
  2. flyNfrank

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    Any mods on your quad?

    I have had to reboot everything at times when I couldn't get the right gps reading. The late afternoon is always the worse for my common launch point. At that time of the day 2 of the satellites are positioned on the other side of my house.

    Btw, I really can't say for sure what you have going on until you post the details on your quad and any apps you use.
     
  3. general01

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    It's stock no mods
    The app is the dji app(latest version)

    I used the Satellite locator app for iPhone and it showed multiple satellites in the sky(haven't really figured that app out fully yet)

    This is a first for me and i haven't had it happen before(I even did a night flight once no problems)

    It was the p2v+ I was flying today(got to fill in my profile info soon)
     
  4. Meta4

    Meta4 Moderator
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    Unless your Phantom is new in the last month or two, it has a flaw in the shielding of the GPS system.
    This requires the foil mod to fix it. It is easy to do and solves your GPS problems.
     
  5. general01

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    It's not new(ver 2) so I guess it needs the foil mod

    I seen a thread on here that covers that but forgot where it's at
     
  6. jasonnelson007

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    I only got mine at Christmas and its the Ver 2 and I get great sat reception. 10-12 always when flying. Is it possible that some are good and others are not even though its the same model?
     
  7. happydays

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    It also depends on where you are flying...
     
  8. QuadCopper

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    Are you flying in NAZA mode? If so, any reason you didn't land with ATTI?
     
  9. BlackTracer

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    NAZA or not, he effectively landed in ATTI cause he had no sats below 80 feet.
     
  10. QuadCopper

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    Correct... just wondering why the alternate landing site.
     
  11. general01

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    The reasion I landed in a alternate spot was due to trees(didn't feel comfortible bring it in near trees with atti)
    I have flown in naza mode many times(rarely fly in phantom mode now)
    Never had this happen before(hence why I posted)
    I have two phantoms a phantom 2 vision and a phantom 2 vision plus and both took longer then normal to find a gps signal yesterday
    Due to this I plan on doing the foil mod and upgrading the gps antenna on both birds
    I did land safely though and without a tip over but it did make me nervous as I was flying with light winds during the second flight
    Got great video footage during my first flight the second flight was just me testing the gimbal's ability to stabilize the video footage in flight at higher speed(did great)

    I checked upswing satalite locator and now I think I figured it out today as it shows the sats in a completely different angle from yesterday(yesterday it was pretty much a weak signal day for me) yesterday the sats was north east of where I was standing today they are in the north west of my area
     
  12. msinger

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  13. QuadCopper

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    Trees can be scary :)

    I know your post is about the GPS losing link, but if this is the regular place you take off/land, I would recommend training in ATTI to get the hang of its characteristics in this area. Build your confidence without GPS to fly in emergency situations.
     
  14. Great Pumpkin

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    The positions of the satellites relative to any point on the Earth are constantly changing, so you cannot expect the same coverage today that you had yesterday.
     
  15. general01

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    I would have if it hadn't been windy during the second flight

    I will be practicing landing in atti mode more as I will need to before I tackle manual mode
     
  16. general01

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    Thanks for the links they will help a lot
    I will be checking it soon and likely get the upgraded antenna soon
     
  17. general01

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    Good point
    I checked today just before I flew it again and my phone's app couldn't see the sats(cloud cover) but the bird seen four on the groundso I flew the entire flight in atti mode(no wind though) and found more as I flew(I have the dynamic home
    Point feature on

    The only reasion why I landed at a alternate spot was I didn't want the wind to blow the bird into a tree and risk damaging the gimbal since I haven't had it long and don't want to have to buy a new camera/gimbal package too soon

    If I was flying my p2v(non plus) I would have landed it regardless
    I guess I am being overprotective of my vision plus
     
  18. Meta4

    Meta4 Moderator
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    Despite what some people may say, cloud cover has no effect on GPS satellite reception. GPS navigation wouldn't be much good if it did.

    You definitely need to do the foil mod. The GPS interference issue is a major flaw that DJI took too long to correct.
    After the foil mod you'll probably have 10+ sats all the time and get sat lock much quicker.
     
  19. StangLuvr

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    Anyone use the upgraded GPS antenna? If so, how much did it help? I am scared to death of dropping satellites again during a flight and almost losing my P2V+.
     
  20. general01

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    Will do as both my phantoms need it(my p2v+ is version 2)

    I always wondered if the cloud cover had an effect on it glad to know it doesn't