Earth ground question

Discussion in 'General Technical Questions and Answers' started by KE0STP, Jul 3, 2018.

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  1. KE0STP

    KE0STP Ham Member QRZ Page

    As I prepare for building a station this winter, I’m working on some Various preparations. Installing an earth ground will be easier to do now in soft sandy soil so I’m going to drive a rod. I have seen that some people drive a 4 foot rod, 8 foot rod, 10 foot rod, and some who then also run a wire onthe ground around the house. Why go to such extra work? Is it a mis-conception that more just has to be better?
     
  2. WA9SVD

    WA9SVD Ham Member QRZ Page

    Until you have a close call with lightning. Even an indoor dipole can experience an EMP from a near-by lightning strike if not properly grounded. YMMV, if you see differently... or feel lucky.
     
  3. WB1E

    WB1E Ham Member QRZ Page

    A ground is not a ground. Better said, there are different quality ground designs. Like SVD said above, until you have experienced a lightning strike migrating in the wrong direction , the more grounds, the better
     
  4. K6BRN

    K6BRN XML Subscriber QRZ Page

    Joevano:

    A VERY common question - so lots of answers exist. But none are simple. Do some reading first - grounding can have three purposes: 1. AC/DC safety, 2. Stray RF control, 3. Lightning mitigation (including static build-up and nearby hit induced voltages/currents, not just direct hits). Each demands different abilities from the ground system. So building a grounding system that meets all three needs - AND avoids significant "ground loops" with your existing house ground) can be a challenge. There is info all over the web about this. For information tailored to radio amateurs, try:

    http://www.arrl.org/shop/Grounding-and-Bonding-for-the-Radio-Amateur

    and

    https://forums.qrz.com/index.php?threads/grounding-dos-donts-why-part-1.335582/

    https://forums.qrz.com/index.php?threads/grounding-dos-donts-why-part-2.335740/

    https://forums.qrz.com/index.php?threads/grounding-dos-donts-why-part-3.338689/

    Brian - K6BRN
     
    KB0MNM and WB5YUZ like this.
  5. KA9JLM

    KA9JLM Ham Member QRZ Page

    More is not better, If you hit something important under ground. :oops:
     
    VE3CGA, KB0MNM and K8MHZ like this.
  6. W4IOA

    W4IOA Ham Member QRZ Page

    If you're planning on using a sledge hammer to drive your gound rod I'd rethink it.
    I use a t-post driver to drive my 10' ground rod. If nothing like a boulder gets in the way you're done in a few minutes. I bought mine at the hardware store ans use it quite a bit in my garden and in antenna work and FD. Beats a hammer every time.
    If you did run into something you can't pound past the rental stores have drivers to rent that really put the muscle into driving ground rods.
     
  7. WB5YUZ

    WB5YUZ Ham Member QRZ Page

    I hope OP doesn't get discouraged by the wide variety of answer he will get to this one.

    The subject of station grounding is complex. Many amateurs like to break it down into two aspects; lightning protection, and antenna efficiency.

    As far as lighting protection goes, in this modern America we have a thing called the National Electrical Code, or NEC for short. In and of itself it is just a set of guidelines, but these guidelines have been widely adopted in several areas, including local codes and insurance policies. This generally means if you do have damage from a lightning strike, most insurance companies are more likely to pay off if you have followed NEC guidelines, even though they are not anti-lighting guidelines per se. Hey, it's a complex world.

    In most amateur radio installations, following NEC means that the shield of a coax feedline should be grounded where it enters the building. This ground point should be bonded to the main electrical ground of the house, at the breaker box or nearby. If the coax cannot be brought into the house near the breaker box, the ground rod used to bond the shield to ground should also be bonded to the breaker box.

    In some ways NEC is completely inadequate to address typical amateur needs. For example, it also requires that any tower or other antenna support structure also be bonded to the main electrical ground of the house; not always practical if the tower is located many scores of feet from the house! So, we have to adapt NEC as best we can. But there is a widespread consensus that grounding the shield where the coax enters the building is good practice.

    As far as antenna efficiency is concerned, the ground system required varies with the type of antenna installation, and many well-equipped stations do not have a special "RF" ground per se. My own station has one, but I didn't know what I was doing when I built it, and it probably doesn't do much if anything. I still make plenty of DX contacts, and lots of others using dipoles, beams, or loops who don't worry about "RF" grounding do, too.

    On the other hand, if you are going to use verticals or certain other types of antennas, a good radial field is often required, although it is perhaps better to think of the radials as a return path than a ground per se.
     
    WQ2H likes this.
  8. AF7TS

    AF7TS Ham Member QRZ Page

    In your reading make sure you understand the requirement for bonding various grounding electrodes together.

    All of the grounding electrodes which interact with the same piece of equipment should be bonded together. Electrical code requires that all grounding electrodes associated with a structure be bonded together.

    Doing this while achieving a good RF design is not trivial, and you will have compromises.

    73
    Jon
    AF7TS
     
  9. N4MTB

    N4MTB Premium Subscriber QRZ Page

    In the antenna form there is a sticky (at the top) of the section that is about bonding and grounds. It answers allot of your questions.
    good luck and have fun.
     
  10. KE0STP

    KE0STP Ham Member QRZ Page

    Yea I’m finding that there is no such thing as a simple question in this hobby. It is discouraging. When I go to the local radio store, I can’t get the guys there to talk down to my level, they always go out on long dissertations about antenna theory or whatever.
     

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