There's a difference between Rx/Tx antenna and normal ones?

Discussion in 'Free To Air (FTA) Discussion' started by enb141, Jul 6, 2018.

  1. RimaNTSS

    RimaNTSS SatelliteGuys Pro

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    enb141 Even if you get one of those you will still need to find the way how to mount it on the lower feedarm. Could you show some pictures of your antenna and all the spares it has?
    Only the first feedhorn from your previous post can fit to an offset dish, the second one is for PFA.
    So, original CM feedhorn will cost you ~100 bucks, flange LNB may cost ~30 bucks, plus delivery that will cost you ~200 bucks.
    To fix LNB to the feedarm you will need special metal frame, which looks like this IMG_20180708_090230 (Large).jpg If you do not have it in the set, then you need to get it somewhere or DIY.
    And, again, IMHO it is much easier to mount simple universal LNB like IBU and get pretty much the same reception results.
     
  2. Cham

    Cham VE4GLS
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    The BUC transmits on one polarity and receives on the other, so reception is single polarity, and the plumbing is set up to filter out as much of the other polarity and band as possible in order to minimize de-sense from the TX signal. Kind of like a pass band/reject filter combo with waveguides and stubs. The TX signal is well above the RX signal spectrum-wise, so unless the plumbing (waveguide) is modified you won't be able to receive much through it.

    I have a couple of those BUCs here, I admit I have never taken them apart to actually see the plumbing inside. There may be a way to separate the TX bandpass section from the feedhorn, and add an adapter for a second LNB? RimaNTSS might be able to add from his experience here. :)

    The original BUC feedhorn would likely be the best to utilize if you can somehow. I might take one apart later here and see what can be done...

     
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  3. enb141

    enb141 Topic Starter SatelliteGuys Pro

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    That's the piece I'm looking for, where can I get one of those pieces?

    I didn't know about that, thanks for the explanation so that means it's gonna be useless to use a Tx-Rx LNB for tv reception.
     
  4. RimaNTSS

    RimaNTSS SatelliteGuys Pro

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    If you sure this is exactly what you are looking for than speak to me :)
     
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  5. enb141

    enb141 Topic Starter SatelliteGuys Pro

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    Sure I will, I just need to get the dish first, as soon as I get it I'll let you know
     
  6. RimaNTSS

    RimaNTSS SatelliteGuys Pro

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    Under influence of this thread I remembered that there is one antenna needs holder. And that is VSAT antenna with lower feedarm exactly as TS asked. So, made this holder. It is adjustable in all ways. Simple like that. And if you know your antenna and position of it's focal point than it will not be difficult to place LNB in the right position.
     

    Attached Files:

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  7. Magic Static

    Magic Static FTA Geek
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    Here's a pic of the mount I have. It is pretty much the same type as pictured in post #21 this thread.
    DodgeDish 006.JPG
     
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  8. Titanium

    Titanium AI6US
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    The polarization separation occurs in the attached waveguide / divider for the receive WR75 type LNB and the BUC. If a LNB (like the Inverto Black Pro flange type) is mated to the conical scalar without the waveguide / divider, both polarities are available. Adapters are available, but not inexpensive. I would simply align the scalar and the c-120 flange drill a few matching holes, bolt and you are in business with both polarities and a scalar matched to the reflector. :)
     
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