Roof-mounted antennas and lightening strikes

Discussion in 'Over the Air TV By RabbitEars.Info' started by comfortably_numb, Apr 3, 2019.

  1. comfortably_numb

    comfortably_numb Topic Starter Dogs have owners, cats have staff Pub Member / Supporter

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    Really? Sheesh! Was it something I said?!
     
    #21 comfortably_numb, Apr 4, 2019
    Last edited: Apr 4, 2019
  2. Mr. Sheep

    Mr. Sheep SatelliteGuys Family

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    Other than grounding the mount, what you could do is get a coaxial surge protector. Channel Master makes some great ones.

    Sent from my SM-G955U using the SatelliteGuys app!
     
  3. harshness

    harshness SatelliteGuys Master

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    They offer some protection (up to 6,000V). This is about the same level of protection that you get from a conventional surge protector with coax ports such as this one for not much more green:

    Monoprice 12 Outlet Power Surge Protector w/ Coax Protection - 3420 Joules - Monoprice.com

    Gotta make sure you read the disclaimer though:
     
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  4. harshness

    harshness SatelliteGuys Master

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    These issues are all theoretically settled by additions/refinements to the NEC established by the local jurisdiction. I think I saw one poster here that said they needed more than two rods spaced some distance apart to establish the service ground.
     
  5. spongella

    spongella SatelliteGuys Pro Pub Member / Supporter

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    Also, always disconnect all outdoor antennas during thunderstorm season.
     
  6. jorgek

    jorgek SatelliteGuys Pro

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    By properly grounding the mast, aren't you just making it into a lightening rod?
     
  7. comfortably_numb

    comfortably_numb Topic Starter Dogs have owners, cats have staff Pub Member / Supporter

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    Once the repack ends in my market (next Friday) I'm planning to use my attic antenna exclusively. It just isn't worth the repeated lightning damage I've received from roof-mounted antennas over the years.

    Plus, I'm almost 40 now, and I'm not the spring chicken I once was. I don't mind climbing on rooftops but fear if I fall on my ass, there won't be anybody around to find me.

    Now that I've canceled my Dish Network service, I hope to be done with roof climbing permanently.
     
  8. jayn_j

    jayn_j Press On Regardless Supporting Founder

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    Yeah, pretty much. But the purpose of a lightning rod is to discharge potential before it gets to arcing stage (lightning) and to provide a low resistance path to ground. The higher resistance of your equipment gets hot and fries if it is the main conduction path.
    How Lightning Works

     
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  9. harshness

    harshness SatelliteGuys Master

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    You have no idea, youngster.
     
  10. jorgek

    jorgek SatelliteGuys Pro

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    At 70, I have no issues going up on the roof and tinkering or is it tweaking my OTA, FTA and ham antennas!
     
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  11. Foxbat

    Foxbat Addicted to new HW Supporting Founder Lifetime Supporter

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    You could always use a lightning suppression system like NASA employs at their launch facilities.
    [​IMG]

    Oh, wait, that's right, you don't have a billion dollars to protect you $1,000 receiver…
     
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  12. comfortably_numb

    comfortably_numb Topic Starter Dogs have owners, cats have staff Pub Member / Supporter

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    Not me; I've got all my stuff on the ground or in the attic and I aim to keep it that way :D

    My grandfather was in his 80's and still climbing trees. Brave man.
     
  13. primestar31

    primestar31 SatelliteGuys Master

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    Luckily, he also doesn't have hydrazine-packed rocket engines. Just waiting for ignition from whatever.
     
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  14. jorgek

    jorgek SatelliteGuys Pro

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    Wow really out on a limb! lol
     
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  15. navychop

    navychop Member of the Month - July 2014! Pub Member / Supporter Lifetime Supporter

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    A friend of mine’s grandfather was up a tree, trimming it with a chain saw. He was in his eighties. He came down, said he wasn’t feeling well, sat at the base of the tree and died.

    Maybe we aren’t making ourselves like we used to.


    Sent from my iPhone using SatelliteGuys
     
  16. harshness

    harshness SatelliteGuys Master

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    We're not doing ourselves any favors with diet balance and chemicals to be sure, but the human heart loses capacity to beat like a hummingbird as we grow older. There's a formula for maximum heart rate that is inversely connected to our age: 220 - age.

    At some point, the heart is damaged by unusually high activity and this damage is cumulative.
     
  17. Wireless Engineer

    Wireless Engineer SatelliteGuys Family

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    ALL antennas MUST as a MINIMUM be grounded according to NEC
    code.
    There are many myths, hoaxes, and wives tales regarding lightning in the ham radio community as well as the public.
    The FACT is lightning CAN and WILL strike anything in order to complete the connection to earth.
    Using the largest surface area ground conductor possible directly from the antenna mast to ground is the best protection.
    If your ground clamp accepts a maximum of #6 guage solid copper then that is what you use.
    Ideally copper strap like what polyphaser sells is the best way to go.
    I always run my antenna grounds directly to a 10 foot ground rod via the shortest route without making bends in the conductor.
    I then bury a #6 bare copper bonding jumper back to the entrance ground rod in order to satisfy NEC code.
     
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  18. charlesrshell

    charlesrshell SatelliteGuys Crazy Pub Member / Supporter Lifetime Supporter

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    Good info Wireless Engineer. What is the allowable distance for the #6 bare copper bonding jumper from the 10 foot ground rod back to the entrance ground rod in order to satisfy NEC?
     
  19. jorgek

    jorgek SatelliteGuys Pro

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    I agree as we age we have to adjust. However, the heart is a muscle and needs to be exercised (within reason) to stay heathy.
     
  20. harshness

    harshness SatelliteGuys Master

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    Not all exercise is good and how much you can get away with depends a lot on your conditioning. If you exercise well beyond your conditioning, damage is likely to occur.
     
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