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The new V+ under the shell, GPS Shielding and more!

Discussion in 'Phantom 2 Vision + Discussion' started by AsiaFlyer, Nov 4, 2014.

  1. AsiaFlyer

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    Posted by someone on the V+ Owners Facebook Page, I like the new GPS shielding
     

    Attached Files:

  2. fastsmiles

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    Looks like they are listening. Maybe there will be fewer flyaways, now.
     
  3. AsiaFlyer

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    Too late for many people

    I wonder if we send our V+ for dropping sats when recording video and poor sat lock they will do this mod for free?
     
  4. 4wd

    4wd

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    What are those ferrite cores fitted to, we could do that perhaps.
     
  5. varmint

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    Those things can be fairly heavy. I'm not even sure I'd want those from the factory, but I'd be curious to know how much they weigh.
     
  6. saltire

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    Dji copy cats ha ha
    https://www.dropbox.com/s/7q6omlpp41u4d ... D.jpg?dl=0
    I already did this and just for info they weigh nowt .
    What they did not need to do was sheild the gps any more better if they cured the original issue which stems from the camera which they have tried to do by using ferrite but i think that fitting ferrite sheeting inside the camera case would be more benificial but at least they are trying all be it too late for lots of owners unless Dji do a recall for V+ owners but some how i doubt it .
     
  7. HunterSK

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    Thanks for the photos AsiaFlyer and saltire.

    I'm wondering, what signal leads are the ferrite beads applied to? Any idea why they didn't have a ferrite bead on the GPS lead itself?
     
  8. saltire

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    Because its not the Gps causing the problem its the camera .My Gps works 100% perfect untill i switch on the camera .
    The ferrites are fitted to the camera leads .
     
  9. 4wd

    4wd

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    Not too bad, they are sometimes fitted on camera USB leads for example.
     
  10. HunterSK

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    Yes I too get a drop in satellites when I start video recording, but my camera is technically always on as it is feeding video for FPV all the time.

    Are you able to comment on what effect the split ferrite beads had on your GPS performance? I might purchase some toroidal ferrite beads this weekend and install them on the camera leads. I have not installed a secondary GPS shield yet, as I think it might be better to solder a ground connection to the existing shield (at least in theory).

    Before I make mods to my Phantom, I'd really like to understand where all this interference is coming from! I don't have the equipment but I'd really like an RF analysis of where the interference is coming from and what the spectrum looks like. I guess for now I'll just depend on seeing what kind of work has been done by others.
     
  11. saltire

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    Having spoken to various people like seasoned Radio Hams who are well up to speed on rf interference and the owner of Horizon antennas a spectrum analizer is what is required to pin point the exact source of interference but as the problem gets worse the higher resolution you select on the camera its a 99% deffo that it is coming from there thats why Dji have fitted these ferrites to the camera cables in the picture .
     
  12. Nathan Carter

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    I'm wondering what is the explanation why some of us don't experience any loss of GPS satellites reception when starting video recording or using the camera in anyway?

    I personally never had even one satellite drop when using the camera. I only had issues acquiring enough satellites at the beginning depending on the part of the day. Probably attributed to satellites constellation...

    Could it be that the process of recording to SD card causes the issue? That would explain no interference when only using the camera for FPV. And if so could it be that different types of SD cards behave differently? Like, that some do cause interference and some don't?

    This is the card I use:
    [​IMG]
     
  13. HunterSK

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    OK thanks saltire.

    According to datasheets from common ferrite beads, they could be trying to attenuate 1 - 300Mhz spectrum. It's impossible to tell unless the beads are identified.

    Have you noticed any difference with your beads on?
     
  14. HunterSK

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    Yeah I use the same card. What would be interesting is remove the camera completely (or turn it off), and see how many satellites are picked up. I think removing the camera gimbal from the Vision+ may also stop the data telemetry being sent (I haven't tried it myself, so happy to be corrected).

    The interference is coming from but it's definitely within the camera system. My guess is that the recording of video causes more of the internal logic to function and it just spews more RF energy out to the rest of the aircraft.
     
  15. Nathan Carter

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    Hmm, so you use the same card and yet you get satellite count drop :-/. Then my theory is not valid. So your theory is that it is not that I'm lucky to accidentally have a camera that does not produce interference, but that I'm unlucky to have a camera that produces so much interference that right at the start I have poorer GPS reception and later when I start recording there is no change because it's already poor enough.
    Could be.

    Before Phantom I had Blade 350QX in combination with GoPro hero 3+ black, that thing was interfering like hell on highest video setting. Immediately upon lift up 350QX would drift to one side. Lower resolution, everything fine.
     
  16. HunterSK

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    Hi Nathan,

    Have you tried tucking the GPS cable underneath the original GPS shield? See if that makes any difference. People have also tried installing a second GPS shield, and as you can see the new Vision+ (ver 2) has this done as well.

    Also, have you tried this experiment. Get a metallic anti-static bag (like from your last computer component purchase) large enough to go around the camera and fit it on and see what affect it has on your GPS performance. Obviously you can't fly this way, but it'll give you an idea on what the camera interference may be doing.

    What I really want to know is if the GPS module in the new Vision+ uses a more recent Ublox GPS receiver?

    The latest Ublox GPS receivers not only receives GPS (the US systems), but also GLONASS (the Russian system). This would effectively mean a doubling in potential satellites to receive, and would give us much better performance.

    I read that the Ublox 8 system even is upgradable to Galileo (the European system which is not fully operational until 2019) and QZSS (the Japanese system for 2017), which means several more a global satellite constellations to utilize. The Chinese with their BeiDou system in 2020 are also sending up their constellation.

    I would love a GPS upgrade. I reckon in ten years time, we won't be having any problems with Global Positioning using the technology available then.
     
  17. Nathan Carter

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    No I have not, have to build up curage to open her up :-/. And mainly I did not do it because whenever I use it in late afternoon I get superb reception. Just seconds after powering up there are 8-9 sats and when I take off I get up to 12 sats and no drops when I press video recording.

    While around noon I can't get more then 5-6 sats on the ground... And then my father comes around with his android phone and opens up the GPS status app and brags how he is getting up to 20 sats at the same location! Probably because it uses all the different GPS systems out there
     
  18. saltire

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    After fitting the ferrites i did not see much difference whilst pressing the recording button but i tried the anti static sheilding on top of the camera and it has made a difference so i am going to line the bottom of the quad with copper sheilding and open up the camera and line it with ferrite sheeting which is £25/$40 for a small 100mmx100mm sheet .
    I do find it strange that only some quads get the sat drop out when recording .
     
  19. 4wd

    4wd

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    I've never touched mine and it's usually on 8-12 with no effect noted from what I do with the camera.
    Clearly there is an issue with some set ups though.
     
  20. Foosy

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    First of all I want to thank all those that are experimenting to get to the bottom of this interference issue.

    Since the difference between camera recording on and off is not always significant, I would recommend to remove completely the GPS shielding before testing. Then try to shield the various camera assemblies individually, and see which one produces the best result.