Over the air antenna question

Discussion in 'Playback Devices' started by Matt Weldy, Jan 25, 2004.

  1. Matt Weldy

    Matt Weldy Second Unit

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    If I want an hdtv over the air antenna. How many times can this be split. I am needing about 18 times split.
     
  2. Don_Berg

    Don_Berg Supporting Actor

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    Thats too many.
     
  3. Patrick Sun

    Patrick Sun Moderator
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    You'll need some boosters/repeaters in between the antenna and each feed...but 18 does seem excessive. You'll need more antennas.
     
  4. Dave Milne

    Dave Milne Supporting Actor

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    Definitely a job for one (or several) good distribution amplifiers...

    A (sort of) related question: do the little in-line "barrel" F connectors cause a significant signal loss? I'm updating an old house for HDTV and it would be a lot easier if I could put a few "breaks" in the cable.
     
  5. Patrick Sun

    Patrick Sun Moderator
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    The rule of thumb is that each split causes a 3dB loss in signal strength.
     
  6. Anthony_J

    Anthony_J Stunt Coordinator

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    Don't need to get too personal, but why do you need to split 18 times? Are you wiring some sort of control room to mastermind your evil plot to rule the world? [​IMG]
     
  7. Dave Milne

    Dave Milne Supporting Actor

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    Thanks, Patrick
    I'm aware of the 3dB (I've heard numbers as high as 4 dB) for a split, but I'm just talking about joining two cables to make one longer cable. How much loss is there in the coupling?
     
  8. Patrick Sun

    Patrick Sun Moderator
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    That's a function of the total length of the run of cable (the resistance of the cable gets higher as the run gets longer, which would cause signal loss). But unless we are having to consider super-long runs, you should be okay.
     
  9. RoyGBiv

    RoyGBiv Stunt Coordinator

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    Using an in-line "barrel" connector to make a longer run should not have any effect on signal strength. The ones I have seen are listed as "0 db insertion loss" which means that there should not be any signal change. This is different from a splitter where there will be 3 db (i.e. half the signal) loss for each split.

    Matt, I would recommend some good distribution amplifiers for what you are planning to do. If you decide to use multiple antennas, make sure that they are not right next to each other. I don't remember the minimum, but I believe they should be 20 or 30 feet from each other to prevent problems with multipath.

    SMK
     

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