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Here's what I have come to know about lightning.? The trick with lightning is less about ground and more about making sure that the lightning's energy is routed past (not through) you and your equipment.? Disconnecting the equipment is a common and effective method, so long as it can be done well before any strikes.? Being caught in the act of unscrewing that last connector when the strike occurs will get you a cameo appearance on a Saturday morning cartoon...? And, to be clear, a "strike" doesn't necessarily involve a direct hit.? Anything within miles can result in a significant local disruption.

The best approach involves two points.? First is to provide a path to Earth - where the lightning strike was going in the first place - that goes past your shack.? Lightning arrestors on all lines with a stout connection to a proper ground rod is a standard means to do this.? During a strike, the arrestor conducts the current coming down from the antenna to the ground rod, instead of letting it continue on the coax into the shack.

Second is perhaps the trickier part, and where that non-direct strike effect is dealt with.? A non-direct strike will raise the potential of the earth itself, but in an uneven way.? Closer to the strike will be higher than farther away.? The problem is that you need to make sure that all of your equipment - ALL of it - remains at a common voltage.? Note that this doesn't mean that it remains at a constant potential, but it doesn't have to.? Consider birds sitting on power lines; they don't care that they are at a kilovolt or two above ground because there's no current going through them.? Not so the squirrel with one paw on the line and another on the metal support pole.? So, make sure that everything has a common "ground" connection to each other, and to that same place the lightning arrestor is connected.? The lightning arrestor will rise in potential above ground during a strike, but if everything else rises exactly along with it, no current will flow.?

The complicating factor is when things are separated, which they usually are.? In my house, for example, the shack and its "ground window" are on one side of the house, and the electrical panel (where the equipment power is sourced) is on the opposite side.? I need to be sure that a strike doesn't raise the potential of the ground window and all of my equipment that's connected to it different from the electrical system they are plugged into.? If they did, then there would be a surge of energy through the equipment into its power cord and over to the electrical panel which has its own ground.? That means that I needed to run a wire to bond the ground stake on the ham side over to the electrical panel's ground to keep them at the same potential.? To this end we ran a fat wire (#6, I think) from one to the other.? But to this thread's comments, I did not mess with how the electrical panel manages its grounding with respect to the safety (green wire) and neutral (white) wires.? That's set by the local electrical code; here we connect them together, but that varies around the planet.? I only bonded the shack ground stake to panel ground, at the same place the panel's existing ground is attached.

Hope this helps,? (and that I got the details right!!).

Greg? KO6TH