Masthead amplifier power issue

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  • Tom41
    Badcaps Veteran
    • Oct 2005
    • 336
    • England

    #1

    Masthead amplifier power issue

    We have a masthead amplifier on our outdoor TV antenna to improve reception, with a power unit indoors that sends +12v DC up the antenna cable to power it. But whenever a TV is connected to the antenna cable in the living room, all other TVs in the house go off and the PSU shows a red light instead of green. I just checked with a multimeter, and the masthead is sending the +12v straight back down into the living room instead of the signal! The other TV points in the house show no voltage on the antenna cable.

    The amplifier is designed to accept power from any of the TV points in the house, but it should not be sending the power straight back down into one of the TVs! Any idea how this happened? Has the masthead developed a fault, or did the installer get some wires crossed?
    You know there's something wrong when you open your PC and it has vented Rubycons...
  • dick_barton
    Badcaps Legend
    • Aug 2015
    • 6642
    • Wales

    #2
    Re: Masthead amplifier power issue

    It may be helpful if you say what make and model of the amplifier.
    Willing to help but I'm no expert.

    Comment

    • CapLeaker
      Leaking Member
      • Dec 2014
      • 8064
      • Canada

      #3
      Re: Masthead amplifier power issue

      Maybe draw a little schematic, how you have your TV's and that mast mount pre amp set up and upload it here as an attachment. Then we can tell you what is wrong. If you put a DC blocker on that living room TV, then probably everything is going to be fine.

      Comment

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