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GPS sensitivity

Discussion in 'Phantom FC40 Discussion' started by landwomble, Jan 7, 2015.

  1. landwomble

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    Hi all.
    I just fitted a Chinese gimbal to my fc40 which works fine, but I'm worried I've affected gps sensitivity.
    It could just be the cloud cover here but since I powered up and tested in not getting a full green GPS flash - it's flashing a single red like its not seeing a full complement of satellites.
    I removed the top casing to wire in the gimbal, is it likely I've upset the GPS connection ? There are two captive ribbon cables attached to the top shelf which I didn't disconnect.

    Gimbal was wired to aux power cables. I've also got a tilt cable connected to f2 on Naza running out of the leg with the compass ribbon cable.

    Hopefully I'm just being paranoid but would appreciate your thoughts.
     
  2. crash1sttime

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    Looking at the Naza lights

    [​IMG]

    it states it has less than 7 sats, still enough to fly though, wait a few days and see if it improves,

    My suggestion is to remove the top and check the cable that connects the GPS to the board is secure, there has been reports of the cable sitting loose in the socket.
     
  3. J.James

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    also if you still have the shell off. peel back the gray foam on the top of the shell that covers the gps and check that the end of the compass wire did not come lose at that end were it plugs in to the gps if you have one of ones were the compass wire also runs up in to the gps puck instead of plugging directly in to the board.
     
  4. dtitus6297

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    Look around for some sticky foil tape, made of copper to isolate the gps unit from the underlying components. They had a kit on ebay before but I can't seem to find it now. You just stick it under the gps, nice and easy and the vision guys use em too
     
  5. IflyinWY

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    Hello landwomble, welcome to the party.

    Compass' are very sensitive. I would reroute any mods away from the compass cable. Then I would do the compass dance away from any chance of interference. I've had serious issues because of an underground powerline in the frontyard.

    The sticky tape which covers the GPS has a protective membrane to minimize interference. You did leave it in place, didn't you?

    Copper tape is a good idea as long as it cannot create a short circuit.

    If my bird was acting weird and there was anything around to crash into, I would tether it to minimize any damage. Prop guards pay for themselves very quickly when something is going haywire. ;)
     
  6. J.James

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    also if you did peel back that gray foam tape with the copper foil inside When you stick it back down make sure there are no tears in it and the cut out sections on the 4 sides it helps if you over lap them so there are no leaks in the shield.

    Also that sheild not only acts as a shield to block EMI it also works as a reflector and it will bounce some of the gps signal back yup towards the antenna in the gps unit. So it helps in two ways.

    If you put an additional layer of copper foil over it you can cover the copper with some tape so there is no risk of it shorting out on any thing. But the extra layer of foil really helps. I even have 2 layers of the copper liner foam because my bottom one had some tears in it. and I get a much faster gps lock now and even a few more sats then normal on that phantom that has the extra layer.