two 5.8ghz downlinks

Discussion in 'Video Assist & Video Accessories' started by georgemcnabb, Feb 28, 2015.

  1. georgemcnabb

    georgemcnabb Member

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    Hi guys,

    I am running 2 5.8GHZ downlinks on the the cinestar and movi however am getting terrible reception on the movi

    The setup is as follows.

    Immersion 5.8 transmitter with cloverleaf for FPV to 5.8 Flysight Monitor Recevier - Works ok
    Flysight 5.8 Transmitter with cloverleaf (Mounted inside the rear leg of the Movi) to 5.8 DJI Receiver with the standard circular patch type antenna

    Both are set to channels which are wide apart from each other.

    I have seen a lot of people do this but i just cant get it to work. Do i need the same setup the whole way through I.E all immersion?
     
  2. Steve Maller

    Steve Maller UAV Grief Counselor

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    I'd suggest using a pair of LHCP VAS Airblade antennas on one of the pairs. Assuming you're using RHCP on the other one. You may also just have a bad antenna on one end. But alternating RHCP and LHCP is a good way of getting even more isolation.
     
  3. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    You might also try with having the TX two channels apart, then three, then four -- you might be getting some issues with harmonics between the two frequencies -- again, just pure speculation but it's what I'd try.

    Steve's comments about LHCP and RHCP are also valid thoughts.

    How far apart are the two antennae? You mentioned where one of them is, but not the other.

    Andy.
     
  4. georgemcnabb

    georgemcnabb Member

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    Hey guys, the channels are quite far apart they are currently on: (DJI - FLysight = 5705mhz) & (Immersion 5866mhz - Flysight 5860mhz)

    Strangely the immersion to flysight one is having the best reception while the other is almost no picture all the time.

    Have also attached images of where the antennae are located.

    Any recommendation on what antennae to get?
     

    Attached Files:

  5. Steve Maller

    Steve Maller UAV Grief Counselor

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    The one on the MōVI is going to be a problem because it's not vertical. The beam pattern on cloverleaf antennae looks like a doughnut (or a bagel, where I come from). So if the antenna's not vertical (upside down is fine), the beam pattern is going to be rather haphazard. At short ranges like 20 feet or so it doesn't matter, but at longer distances, you're going to have issues.
     
  6. georgemcnabb

    georgemcnabb Member

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    So I should mount it straight down or bend the antenna down?

    Ill try the LHCP thing too. Hopefully that will solve the issue
     

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