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Thread: Dual Fequency diversity. Will it work?

  1. #1
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    Dual Fequency diversity. Will it work?

    Could you use an oracle diversity controller with 2 separate frequencies? For example: 1.3ghz & 5.8ghz vtx on the plane, Ground station with oracle diversity controller, a 5.8ghz and 1.3ghz vrx. The 5.8ghz would use CP cloverleaf on vtx & vrx, the 1.3ghz would use a Vee on the vtx and a patch on the vrx.

    The thought is to utilize the 5.8ghz great image quality for close range (1-2km) and if you venture out past the 5.8ghz range the 1.3ghz will take over.

    Would this even work? I don't think the extra vtx would be too much extra weight.

    Any thoughts? Thanks in advance!

  2. #2
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    I think it should work....
    I bet diversity picks 1.3 most of the time tho... If it does, try swapping the oracle inputs... I've seen diversity favor one input before.

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    Quote Originally Posted by jimmaplesong View Post
    I think it should work....
    I bet diversity picks 1.3 most of the time tho... If it does, try swapping the oracle inputs... I've seen diversity favor one input before.
    Thanks, anyone have any references that this definitely works? or examples of it being done. I would be interested to see other setups with dual band. Thanks!

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    I don't know anyone who's tried it, but yeh, it should work fine. The Oracle switching decision is based purely on the quality of the composite video signal - it doesn't know/care if that composite video signal is coming from two vRX on the same frequency, different frequency, or a DVD player!

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    My concern is degradation of signal or interference with 2 transmitters on the plane. That's why I considered different polerization between antennas.

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    There will almost certainly be some adverse affect of having two vTX on your plane, but to what extent is hard to predict as I'm not aware of anyone who's tried it. Having them transmit on different polarisations has got to help, but you might find it works just as well them both being the same. Just give it a try.

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    Quote Originally Posted by Ian Davidson View Post
    There will almost certainly be some adverse affect of having two vTX on your plane, but to what extent is hard to predict as I'm not aware of anyone who's tried it. Having them transmit on different polarisations has got to help, but you might find it works just as well them both being the same. Just give it a try.
    Thanks for the replies, I guess trial and error is the only way to find out.

  8. #8
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    Quote Originally Posted by Hemmi View Post
    Thanks for the replies, I guess trial and error is the only way to find out.
    When it comes to RF, practice often counts for more than theory

  9. #9
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    It will work fine. The Oracle doesn't care sbout frequency, only video. It switches based on sync pulses from the VRX's. Mind you, the video systems have different processors, so the switching might be skewed slightly. You might have to adjust the video gain of one of the VRX units for top performance.

    -Alex
    If it is broken, fix it. if it isn't broken, I'll soon fix that.

    [url]videoaerialsystems.com[/url] - Performance video piloting

  10. #10
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    The nature of the query was less about the capabilities of the Oracle unit (this was addressed back in #4) - more about the potential of adverse affects by having two vTX in close proximity. It should work, but suck it and see - that's what I say!

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