Or the way I do it.
Okay first I am going to repeat the Stray RF section from the "Wire Antennas" page to get started, then we will go into what I think is your best way to ground your amateur radio equipment, so that during a lightning strike everything isn't fried.
"Use a good grounding system outside. All of your coax from various antennas you might have should to be connected to a single ground point. With a 8 foot long ground rod buried next to and attached to where your coax attaches to it. Use a lightning arrestor on your coax outside where you are grounded, USE A CURRENT CHOKE at the connection to any antenna you own, and ANOTHER 1-1 CHOKE before the feedline gets into the house. You want to keep out any RF before it gets into your house. You know how some frustrating days you just want to choke something, well take it out on your coax and choke it before it gets into your house."
As you can tell part of the problem of discussing RF Grounds is that it covers two grey areas, which get interchanged. One is Stray RF getting into your equipment causing lousy audio output and mini shocks when touching microphones and such. Two is Lightning protection to your shack. They are related but I am going to focus on Lightning first.
There are a couple of things that I believe may help you in a lightning strike. I say "MAY" help, because lightning doesn't really care what precautions you think you have taken or not. It will find the easiest way to "ground" that it can and more likely a RANDOM nonsensical way to get there, no matter what you do. So how do you stop it? You can't, but you "MIGHT" be able to direct it somewhat away from your ham radio equipment.
I personally believe that all the photos you see of wires and coax lines drilled through outside walls and windows going into your shack is a mistake. What I use are outside antenna switches with lightning protectors at the main coax connection, this antenna switch is bolted directly to a 8 foot ground rod. A good distance from the ham shack. Only one run of coax comes into my house. And at that point I have a disconnect setup that has another lightning coax surge protector, so that when I am not home or away, the coax never enters into the shack. The antenna switch or switches outside in my case are all connected at that point to the same grounding rod. If you have beams like me then the rotator cable must also be protected. I connect this to a rotator control line protector (available at dx engineering) this is also connected to the same ground rod. My antenna switch cables are grounded the same way. The coax disconnect switch shown above was made by WR9R in Indiana.
My towers have multiple WIDE flat copper straps that run from the towers to multiple ground rods (3) each 8 feet away from one another. What I am trying to do is help the lightning strike that found the tower, find the easiest way to ground, and that I believe is through multiple ground rods placed some distance apart from one another connected by thick wide copper strapping. So far (knock on wood) I have not had any lightning strikes that have gotten indoors to my equipment and ruined anything. ( Boy I say that with my fingers crossed!! Maybe I shouldn't even mention that. )
Your house wiring also goes to ground, all outlets nowadays have a third round ground plug, that routes any electrical shorts that happen in your home appliances or other electrical items to an outside "SERVICE MAINS" ground. This is usually near your electric meter outside your house, or where your electric comes into the house. This has to do with lightning strikes, but mostly electrical faults in your house, it is designed so that if inside one of your electric devices a 'hot" wire carrying current shorts out, or comes in contact with the outside metal case of your device, the unit itself will not cause a fire and nor will you get a shock if you happen to touch this device while it is shorted. It does provide some lightning protection should your house itself get hit by lightning, since all wiring faults that happen when you got hit get routed to ground.
Again the 3 prong plug on the electrical cord of your ham radio equipment is there so you do not get a shock if something you have shorts out. So technically all of the equipment that you own in your shack is already grounded. Grounded to your service mains. If you had no antenna or coax connected to this equipment at this point, your equipment and its electrical potential behaves like any other electrical device in your house, like your TV or your Fridge. 50 years ago Ham radio equipment needed a ground. This is because we did not have three wire house plugs with the ground connected to your mains. Without these three-wire cord safety grounds, there was a risk of 115 volts appearing on the chassis from faulty wiring and from component shorts. Today most buildings built after the 1960's require 3 prong plugs that safely shunt all excessive electrical current to your service mains ground. One thing to add, don't think a GFCI outlet will protect you from lightning it doesn't..... it is there to stop shorts or electrical imbalances, could it trip due to a lightning strike? Sure it can, hopefully it will. But it is not designed to stop the tremendous amount of energy of a lightning strike. Don't rely on them to protect you.
So why are we taught to connect wires to the back of all your radio equipment and connect it to a separate grounding panel / braid or wire and run it outside to ground it to yet another ground rod? Isn't this creating a ground loop, can't this create stray RF, doesn't attaching wires to your equipment make alot of possible unwanted antenna combos which will add noise and give you other problems? YES...YES and YES. My opinion is you should not do this. In fact you are creating another pathway for lightning to enter your home and fry your precious ham radio equipment. You are also creating a separate ground entrance point to your home which I believe under most building codes is illegal.
So if you are thinking, "but I use thick grounding braid straps and connect them to a flat copper panel or copper rod which then connects to an outside ground rod" doesn't that prevent Stray RF from building in the shack and prevent those mini shocks I sometime get when I touch that old D-104 microphone? Yes it probably will because now this equipment has a common hopefully low to zero impedance ground area. So when there is no lightning threat around your gonna be okay. So isn't that good? Well yes and no.
You have maybe solved some of your Stray RF issues in a roundabout way, The Stray RF issues probably come from RF coming INTO your shack via the coax, from end fed antennas or un balun'ed wire dipoles or other random wires, so yes you have diverted that to a separate ground. Here's the problem.... you have also created a brand new way for lightning to enter your home. Lightning is very random and unpredictable, whose to say it hits the ground somewhere near your ground rod outside, travel up the ground rod and into your house where conveniently all your equipment is now tied to?? Does that sound like a good idea? Picture below from flex radio
IS there a way around this? Sort of: ( If you insist on not listening to me, which by all means you can do. I don't pretend to be a lightning nor a super ground expert.) You could make sure the radio room portion of your house is near where the electric service entrance ground is in your house, and run all of your equipment to THAT ground and ditch the separate ground rod, and you would be within existing building codes (this is a decent option if you can do it) . You could also run a Long Separate Ground Strap from the outside ground rod of your existing radio shack and run that all the way to the service entrance ground provided by the town ( going outside your home of course). You would be legally in code and you will have created the easiest path for lightning to take to reach ground, and keep most of it away from your shack. The key word there is MOST.
All electrical charges at this point would be equal, and eventually terminate at your service mains ground, so far so good. However initial excessive electrical charges would still be directly connected to the chassis of all your ham radio equipment, which in turn is connected through the 3rd prong on the electrical cord which runs through your house to the service entrance mains. So basically some lightning energy now could also run through your home electrical wiring to eventually get to the service mains ground of your house. Sound good? Doesn't to me.
If you do like that scenario ( because you have seen or heard of it before) and insist on having a outside your shack window ground rod, then my suggestion in all cases would be to plug all of your equipment into protected power strips the kind with MOV....Metal Oxide Varistors. (MOVs) are bidirectional and non-linear surge suppressor devices that are widely used for limiting voltage during a surge or transient event in a broad variety of applications. Tripplite ISOBAR power strips have this as well as a few other high quality units. At this point you would connect the ground lug from these power strips to the Braid or Copper grounding bar you made and then connect to the outside the shack ground rod. This will divert all electrical surges back to your ground rod outside. This will also prevent any high power surges from making it to your home wiring..... hopefully.
For me, the idea is to keep lightning AWAY from my ham radio room entirely, provide no path for it to get in at all. This mean one coax with a surge disconnect. (available at dx engineering). Done.
Again if you insist, I don't know what I am talking about or are set in your ways:
If I still had stray RF or RF shock issues (which I don't) ... I would look at the all the wires coming into my ham shack as suspects. These at some point are carrying RF into your ham shack which for them becomes an RF playground of things to excite. It's Disney World for electric charges. Keep them out of your ham shack by grounding everything properly outside long before it gets in. You'll be alot happier. And keep the wire mess under your desktop under control, keep all wires short, and get rid of any extra transformer things you do not need. Like your cell phone charger, also get rid of any LED lights and any other novelty things you don't need. You'll be surprised what could be causing you issues. Plug in all devices to Tripplite or similar ISOBAR (MOV) power strips.
Another side subject that gets virtually no mention when talking about grounding is what you are grounding with. The efficiency of your earth ground system depends completely upon the resistance or Impedance of your ground path. If the ground resistance itself is too high, more noise may be built up that reaches your receiver, instead of being sent to ground. The impedance or resistance should be near to ZERO. When this happens any lightning or other noise coming down the coax shield will readily follow your ground rod to earth and you'll be alot happier and safer. If there is a higher resistance at that point like 1000 ohms+ or so, not all of that energy is going to be depleted through your ground rod. Speaking of which: Why are ground rods 8 feet long? Isn't that a Pain in the a** to get that deep into the ground? Ground rods are that long because during the first 6 feet while its in the ground the earth itself as lots of stuff going on, and is probably highly resistive. Below 6 feet of depth the ground is fairly moist and also a stable temperture most of the year. This means at that point there is less resistance. Is it perfect? No but much much better than only putting in your ground rod 4 feet deep, thinking that's enough. It's not.
The average ground moisture is about 35% in summer during wetter weather and about 10% in a dry fall season. So what you say ! What is the resistance or impedance during a dry season? How about 300K (ohms per cubic centimeter) how's that for resistance? Using the same soil what is the resistance in a wet season? How about 1K (ohms per cubic centimeter). Just to add another wrinkle to the mix, how about summer versus winter? In summer at 70 degrees with average moisture your might have 200 ohms of ground resistance. At 32 degrees the same gound has 6,000 ohms of resistance (ohms per cubic centimeter). How about at 0 degrees? How's 40,000 ohms of resistance sound? Basically you have no grounding at all with a shorter 4 foot deep ground rod. Frozen soil in effect provides NO grounding whatsoever. This is why ground rods are 8 feet deep, to get beyond frozen ground to a more stable temperture where they can do some good.
So what can you do about this? Make sure you drive that ground rod as deep as it will go. 8 feet minimum. Now if your a antenna lunatic, like I have been told I am and not just by my wife! You can before you put in the ground rod in the hole, fill the hole with rock salt. Yep that Ice melt stuff. Not the magnesium chloride stuff or similar chemicals, just rock salt. You can also make sure if you have sprinklers that they hit where the ground rod portion is located in summer. In the winter don't just put rock salt on your driveway but save a few pounds for your ground rod. The rock salt after a while will of course dissipate after a while, but feeding your ground rod once in a while will certainly make the ground around it highly conductive. And you will have less noise and more importantly less chance of lightning making to your house. Since it has already found a great place with low resistance to meet the beloved earth outside of your house. One warning rock salt and grass aren't friends, with rock salt winning that battle easily. Look at it this way, its another part of your yard you don't have to mow!
Correcting the problem of stray RF or Lightning strikes at the source is what I believe works best. Keep it all away from your house or your ham shack.
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