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       Amateur radio grounding theories !!PART-1
   DIR By: K4KGP
       Date: October 6, 2020, 12:38 pm
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       Amateur radio grounding theories
       Amateur Radio Station Grounding
       RCC Mar 2007 - Lane Giard, N7ZXP
       This article comes from Don Young, N7DY, which was in The
       Wenatchee Radio Club News
       letter.
       A good ground system is an essential part of a good ham station
       for various reasons. First and
       foremost, grounding is for the safety of your family, home, and
       ham equipment. Lightning not
       only destroys ham radios, but often starts house fires, thereby
       jeopardizing the safety of your
       family. An elevated antenna or a tower protruding into the
       atmosphere naturally increases the
       odds of a lightning strike. Statistically, most lightning damage
       comes from the AC power or
       telephone lines running into your home.
       Simple ham station grounding is often done with a water pipe.
       Indeed a metallic cold water pipe
       can serve as a basic ground for ham gear. Since outside water
       pipes normally are buried well
       below the soil’s surface, it does serve some purpose. Remember,
       though, that a cold water pipe
       ground should be considered merely one level above a no-ground
       system at all. You can do
       much better. A fact significant to hams is that a good ground
       will not only increase the receiver’s
       sensitivity, but also its transmitting propagation. I have often
       observed a decrease in
       surrounding ambient noise from S9 to S5 on 40 meters by simply
       changing the station’s ground
       by changing a cold water pipe ground using 12 gauge wires to a
       proper RF grounding system.
       Your regular ham contacts will usually notice the improvement to
       your signal. As you probably
       know, HF antennas work best when they work against a good
       counterpoise ground reference.
       Good RF grounding technique is misunderstood and difficult to
       explain in simple terms. It is a
       basic phenomenon of impedance. RF grounding requirements are
       very real, somewhat difficult
       to measure, and unseen in operation. A common term that is used
       in RF grounding is “skin
       effect.” In a ground system the majority of electrons run along
       the surface (or skin) of the
       conductor. A good RF ground has the least amount of resistance
       to electrons being conducted
       to ground. This is obtained by having the largest amount of
       conducting surface area that is
       practical. The goal of a good RF ground system is to obtain as
       little resistance as possible from
       the antenna/tower to ground and then from the radio to ground.
       Thus, the more conductor
       surface area the more ground path conductivity. Effective
       grounding is measurable. A good
       grounding system will measure less than 12 ohms from the radio
       to ground. A typical cold water
       pipe ground will measure fewer than 35 ohms, assuming the water
       pipes are not made of PVC.
       Measurement is both rare and difficult since most hams do not
       have a ‘Megger’ type instrument
       required to make the measurement accurately. For this reason for
       some, a well planned and
       properly installed ground system is the best alternative. Even
       without an actual measurement
       you’ll know it’s as good as you can provide within your means.
       This paper will assist you by
       giving examples of relatively good RF ground systems that are
       often within the means of the
       average ham. OK then, here we go. Several things need to be
       contemplated before deciding on
       your plans for an RF grounding system.
       * You should consider your budget and the amount of effort that
       you are willing to invest to
       obtain a good RF grounding system. It is not to your advantage
       to be cheap or lazy – if so, you
       might just as well use the cold water pipe. Then be prepared to
       buy new equipment when you
       get your first lightning strike.
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