I was sceptical at the title, but watched anyway (i don't want to live my life in an echo chamber ... other opinions deserve air ... well, most do) ... What a bloody interesting talk! Kristen's descriptions of her investigations (both theoretical and practical) are well presented, flow well and convey in layman's terms what's going on with with this very eclectic part of the hobby (radio and electrical). Thumbs up to Kristen 👍 for what must have been a huge amount of work, for me to be able to watch for free, and to Hayden for bringing it out of the lecture theatre, so i could watch it whilst sitting in the comfort of my home eating lunch 🤜🤛
@@jamess1787 Example, a balanced transmission line has no "ground" where you can measure from, yet it has a theoretical ground which is the electrical difference between each side. This is true for many car audio systems as well. Telco circuits also do not have a ground per se. In an automobile that has a positive grounded battery (same for most of the 1960's germanium transistor AM pocket receivers) all the measuring points are of negative potential with respect to ground, so the "point of reference" still stands as to where you are measuring from. Ground is NOT zero volts ever and I think this is what the guest is trying to say, though she doesn't directly come out and say it. 73
@@WECB640 The ground wire going into the ground that is hooked up to the third prong in three prong outlets has zero voltage but that is a different kind of ground.
@@tom-hy1kn I respectfully disagree. That 3rd terminal may have an overall average that we conveniently label as "ground", but if you measure any point on it with respect to another point on the same wire, you will measure a difference in potential albeit small. This is because the wire has some minute value of resistance. You are aware that there are electrical currents that are always traveling through the Earth below our feet. When lightning strikes or when a live mains cable contacts the ground, electricians know to hop away from the point of contact so that they do not have a difference of potential between their feet which could cause a current to flow up one leg and down the other thereby possibly causing death. The ground below is NEVER at zero potential between any two points. Even in a simple ham radio power supply, the current meter is usually measuring the voltage drop across a very low resistance in the ground (return) lead. So once again, ground even within the circuit of the appliance is never actually zero volts. We teach our students that ground is zero potential and we take great liberties in our textbooks to overly simplify this statement for the sake of simplicity, but it is technically incorrect. Unless the conductor has absolutely zero resistance (something not possible despite coming close in a liquid helium chilled superconductor) the internal resistance brings rise to a delta of voltage whenever a current flows. That is Ohms Law.
As I prep my UA-cam channel and start laying the groundwork (no pun intended) for content, this is exactly the kind of topic I want to explore. There’s a lot of confusion around "grounding," as well money and effort wasted. I think it’s time we all take a step back and recognize that what we’re really talking about is a localized safety solution, not some universal law. The more we understand that, the better we can appreciate the role grounding plays in our electrical systems-and the better we’ll be at designing safer, more reliable systems in the future. This is a draft of my first script. I will include the references at the bottom. I like this Lady! Introduction I’ve spent my career working with electricity and electronics-mostly hands-on, a mix of trade school and self-taught, with a degree from the school of hard knocks. Along the way, I’ve learned a lot of things that aren't covered in textbooks, but one thing's certain: in electrical systems, grounding is real-you can’t run a "safe", functional system without it. The problem comes when we start talking about "ground" as if it’s some kind of universal, unchanging reference point. The more you dig into the fundamental nature of electricity, the more you realize that "ground" as a concept becomes less clear when you move from practical, everyday electrical work to the world of theoretical physics. I wrote a deep dive paper into the concept of "ground." While it’s crucial in electrical systems and it serves a very real, practical function, its absolute meaning starts to get murky when you apply the term beyond the world of circuits and into fundamental physics. We’ll be challenging the Dunning-Kruger effect by questioning the myth of ground-the idea of a fixed, unchanging reference point in the universe-and rethinking some of the ideas that get thrown around in both engineering and physics. The Role of Ground in Electrical Systems In practical terms, "ground" serves a very simple "function": it provides a low-resistance path for electrical current to return to Earth, especially during a fault or short circuit. If something goes wrong in an electrical system-say, a wire comes loose and touches a metal casing-the current needs somewhere to go. Grounding directs that current safely into the Earth, preventing shocks or fires. It’s a safety mechanism, plain and simple. Now, here’s where it gets interesting. While "ground" is essential, it’s not the perfect electrical sink many people assume it is. When it comes to grounding electrical systems, a common misconception is that the Earth itself is a perfect conductor, capable of instantly absorbing and dissipating electrical energy. In reality, this idea is far from the truth. The Earth, in its purest form, is actually a poor conductor of electricity. This is because the Earth’s composition-primarily consisting of rock, soil, and water-offers considerable resistance to the flow of electrical current. This resistance can vary dramatically depending on local conditions such as soil type, moisture levels, and temperature. In fact, if the soil is dry or rocky, grounding can become much less effective. So, why do we still use the Earth as a grounding point? The answer lies in the field around the Earth-not the Earth itself. While the Earth may be a poor conductor, the electric field that surrounds it is far more significant when it comes to the flow of electrical charge. (This concept is for a different podcast) The Earth’s resistivity is not uniform-it changes based on soil type, moisture levels, and other environmental factors. So when we talk about the Earth as a "ground," it’s important to remember it’s not an infinite, catch-all sink for electricity. In fact, its ability to absorb current is not unlimited. Grounding, as we know it in the field, is more about providing a path of least impedance, not about dumping all the energy into the Earth. The Misleading Associations of Ground Here’s where the confusion sets in. The word "ground" carries a lot of misleading connotations-especially when we start thinking about it as something more than it really is. The two biggest misconceptions about "ground" are: 1. Ground as Zero Voltage: In electrical systems, we often refer to "ground" as a point of "zero volts." It’s the reference against which we measure other voltages. But let’s be real: zero volts is relative. There’s no universal "zero" across the universe. The voltage at ground is simply a reference point within the system you’re working with. Outside that context, the concept of "zero" becomes meaningless. 2. Ground as the Ultimate Sink for Electricity: The Earth is sometimes treated as the "ultimate sink" for electrical charge-like a vast, infinite reservoir waiting to absorb all the current that comes its way. But the truth is, the Earth has resistance, and its capacity to absorb current is far from limitless. The effectiveness of grounding depends on local factors-soil type, moisture content, depth of grounding rods, etc. So, calling Earth the "ultimate ground" isn’t quite the full story. These misconceptions lead to a misunderstanding of the true role of ground. Grounding is a "localized safety measure" within electrical systems, not an absolute, universal principle. Grounding and Relativity in Physics When we step out of the electrical engineering world and into the realm of theoretical physics, the whole idea of "ground" as an absolute reference point falls apart. Take Einstein’s theory of relativity as an example. According to relativity, there is no universal frame of reference-everything is relative. So, when we talk about "ground" as though it’s fixed and unchanging, we’re ignoring the fact that the concept of a "reference point" changes depending on where you are and who you ask. For example, someone standing on Earth might think of the surface as "ground," but for an astronaut in orbit, their concept of ground would be entirely different. The idea of a universal "zero point" or absolute ground simply doesn’t hold up across different frames of reference. And in the realm of quantum mechanics, where particles and fields are inherently uncertain and fluctuating, the notion of a fixed ground is even more problematic. In these contexts, "ground" becomes a relative term, just like any other reference point. Practical Grounding in Electrical Engineering Now, back to the practical side of things. Despite all this theoretical discussion, grounding is still crucial in electrical systems. You need ground to make sure that your electrical system is "safe". The ground path is a circuit we design and build providing that essential path for current to flow back to Earth in the event of a fault, ensuring that dangerous currents are safely dissipated. But it’s important to recognize that "ground" in electrical systems is a "localized safety feature" we built and labeled, rather than an absolute, universal principle. When you ground a system, you’re not tapping into some infinite reservoir of energy; you’re creating a safe return path for fault currents. The grounding system typically connects to the Earth’s surface (or another conductive body), but the goal is always the same: direct stray current away from people and equipment, preventing shocks and fires. Conclusion To sum it up: "ground" is a critical part of electrical systems. Without it, our circuits wouldn’t function “safely”. But the concept of ground as some sort of fixed, unchanging reference point-that’s a myth. In reality, grounding is a practical tool for managing fault currents and providing voltage references, but it is not an absolute, universal constant. References 1. Alexander, C. K., & Sadiku, M. N. O. (2009). Fundamentals of Electric Circuits (5th ed.). McGraw-Hill. A comprehensive textbook that covers the fundamental concepts of electrical circuits, including grounding and electrical safety. 2. Hewitt, P. G. (2012). Concepts of Physics (8th ed.). Addison-Wesley. A classic physics textbook that introduces the basics of electrical circuits and grounding, along with discussions of reference frames in physics. 3. Griffiths, D. J. (2017). Introduction to Electrodynamics (4th ed.). Pearson. A detailed text on electromagnetism that explains the behavior of electric fields, circuits, and the concept of grounding in electrical systems. 4. Einstein, A. (1915). The General Theory of Relativity. Annalen der Physik, 354(7), 769-822. A foundational paper in modern physics, where Einstein establishes the theory of relativity, showing the relativity of motion and reference points. 5. Feynman, R. P., Leighton, R. B., & Sands, M. (2011). The Feynman Lectures on Physics (Vol. 2). Basic Books.
This is a much more scientific survey of my observations regarding ground ambiguities. Grounding potentials are nebulous and ground loops are elusive especially when crossed with any kind of inductive coupling. Flooding the zone with grounds is seldom a solution. Grounds are commonly lifted at the source in audio studios. I was surprised at the role of coax shield in feel lines of antenna systems and where common mode current might appear. You can know more and not think of everything.
I was hoping she would get into the "separate or do not separate" the analog circuit ground from the digital circuit ground in electronics. From what I've researched, analog circuit components should be kept to one side of the board, and digital to the other, but best practice is for them to both share the same ground plane (I think there is one stipulation where a certain frequency range plays a factor, and so shared ground in very minute circumstances should be avoided). The importance of cable shielding, from my understanding should be seen as an extension of device shielding, as in, many devices are in a metal case acting as a faraday cage in many ways, if a cable that is plugged into the device is properly shielded then the faraday cage would be extended to the cable. She did go over isolation and shielding, but it's helped me to think of cable shielding as an extension of a device's faraday cage. Let's say I have a DB9 serial cable running from my radio to a serial port on my pc (because I'm old school I guess), if I wanted to ensure quality RS-232 signals where being passed for CAT control without picking up any RF and without having digital computer circuitry RFI bleed into the radio, I should use a serial cable with a metal DB9 connector that is connected to the shield of that cable as well as utilize ferrites either along the whole cable or just before connection points. This should get rid of any "cross talk". The part I find confusing or more convoluted is that If all of the devices in your shack are connected together via their ground lug screws/terminals and a bus bar, and then from the bus bar to a ground rod, and then a ground rod every 8ft or 2.5ish meters all the way until you reach your service entry panel (mains electrical service panel) ground rod to connect to it as well, wouldn't that make for a more robust shielded system that ensures the insides of devices can do what they are supposed to without interference from other devices or things? Or, would connecting stuff in this way cause problems with RF being coupled to the ground wire messing with your antenna system and other such things? (I'm sure this would depend on distances/proximity and lengths of conductors) Or, is she just saying that it isn't necessary if you properly isolate equipment with baluns and cable shielding? Technically though, would or wouldn't it be better to have all device case shields be connected to same ground? What is the best thing? Not sure if "it depends" applies here. One thing must be better than the other, even if that thing is not absolutely necessary.
On a side tangent, why were electronics in the 80's/90's so much more heavily shielded than today's stuff (generally speaking)? Was it because they used larger noisier components? Is it because mostly everything is digital and low power now? (cheapo wall warts, inductive chargers, and capacitive touch lamps meat FCC standards apparently...?) And, what is with cheap USB cables? Everybody loves USB C, but finding a USB C cable that has actually been designed to spec, which also happens to be affordable, is not really a thing. (Apple makes a great cable, but it costs booku bucks). How feasible is it from an electrical engineering standpoint to actually be using USB C for everything anyway? I would really like an engineer to explain. Especially if a manufacturer could just use a different cable that is more affordable and typically can be found with better shielding that is built to a more uniformly adhered to standard. One example would be XLR cable, it tends to have far superior shielding than just an AUX audio cable (3.5mm) would that be the reason why keyer jacks on radios are 1/4"? Some are not, but usually that's a QRP thing, and not all 1/4" aux audio cable is shielded as good, but if you type XLR to 1/4" cable you will get the good stuff, and then just chop off the XLR end and direct wire to your paddle/ straight key.
I do think this is over complicating the matter. It’s only a myth if you think of ground or earth, as some universal and ubiquitous zero potential thing, and every time you see the word or symbol for ground or earth, that they are part of it. Does anyone think of it like that? Possibly but only people for whom it’s not actually relevant. I would think any electrician, electrical engineer, just about any other Engineer, amateur radio operator, and so on, understand that it’s nothing more than the side of the voltage supply not called positive.
I think gnd matters more when dealing with static charges or lightnings than RF. Well this begs question how a static charge can influence an equipment ? - Maybe it has something to do with the shape of a casing, where some sharp corners could lead to the E field gradient not being an uniform distribution or in case of mosfets they have insulated gate so in rare examples where the body is not connected to the source of a particular mosfet that may cause too much potential difference when charged statically semiconductor's body but not the gate since the gate's dielectric was in neutral charge state before. So maybe it is necessary to do some experiment on equipment with outside UV charging.
I found this very interesting. I do not run a ground for RF from my modest shack (upstairs). I work all bands 6-80m with very low SWR and low noise. I do have a MFJ-931 Artificial Ground, but I have never felt the need to use it. I may try it on the back of tthis presentation as it is just a tuner for a counterpoise. Currently the only Counterpoise I run is directly under my EFRW. Thanks for the video. 2E0GKF
I've worked 159 DXCC entities with my humble setup. Happy with that after one year on HF. I've learned loads about propogation working Digital that will serve me well in the future. I don't get many problems with lightning, if there is a risk, I disconnect the antenna's or take them down.
Are there any dowsers here ?. I find that selecting house ground stake location has subtle but important effect on performance of A/V equipment in the house. Anybody noticed change in RF rig performance according to earth stake location ?.
The effects of ground or earth varies from DC to White Light. It can be a conductor, attenuator or reflector, depending on frequency and distance relative to free space. RFI in the shack is a different matter. An antenna must be matched at its terminals to coax and located far enough away depending on power. Consider a high power broadcast station. Still, an important subject and there are many engineering level books free on the web.
Its horses for courses. The trouble is a good long ground rod giving low resistance for a power installation, would have too much series inductance to be much good at RF. I suppose a clever clogs could tune it out with series capacitance, why bother though, a ground mat or radials are a lot easier to deal with.
18:43 actually if you take your dipole and the tree is too small, just let it hover over the ground and it still works fine. You need just one radial. For a low SWR about 30 cm worked fine for me on the 20 m band.
"Ground is a Myth!" I'll go stand on it and see for myself. Anyway, at radio frequency, unless your radio is sitting on the ground, it isn't at ground potential.
Ground is not a myth, ground is the name of a concept to communicate about with each other. This video shows that ground is just not what Kristen McIntire thought it was before. I want to emphasise what she says about lightning. That part IS most important to have a ground. Lightning could only strike once in 20 years in your area, but let these 20 years not give you the impression you don't need (earth)ground.
I’m a British 🇬🇧 Foundation Licence holder M7EOM I would like to Thank you for teaching me this I’ve certainly taken on board what you’ve said thanks again Kristen
You forgot one. It's a source and sink of unlimited free electrons. The Earth has zero net charge. Connecting to it neutralizes any positive or negative charges that might otherwise build up on conductors.
There are not unlimited free electrons, also the earth is actually negative in that it has a surplus of electrons. Connecting to it only bonds to earth (the ground) so you remove any potential difference between your thing and the earth
But it doesn't. When a highly negative cloud base edges over you but not over the power company transformer, the green ground and the white neutral (commonly connected in the main circuit breaker (US, I've read that Brits have a variety of systems)) your antenna shield can be at a different V than a grounded mast. Also, high current in the wiring can mess up neutral potential, as well as send voltage spikes about.
@@LarryAllenTonar If your coax shield is bonded to ground where it enters your shack like it is supposed to be then you wont have that problem. And if the ground didn't sink that charge, everything metallic would be at hundreds or thousands of volts of potential every time the wind blew or a thunderstorm wandered by.
Except when you stand on your head or being drunk. Indeed, it's all relative. Ground is not a myth, ground is the name of a concept by which we communicate about it with each other.
rubbish, ground does make a difference!!!!!!!!!!! cant listen to this absolute rubbish, its alays the americans who have the odd ideas...is that something to do with all the additives in the drinking water..?
@@jonniez62 What she states is not a theory but what I can say is ham radio is all about "radio" thus electromagnetic energy being radiated and this is very much affected by the ground effect, if she really wants to know more about the subject I can recommend the multitude of excellent publications by the ARRL, like chapter 3 of the ARRL antenna Book to start off with....
Maybe you could publish the new revised and recommended by ARRL best practice ham shack setup , to include where if any and all equipment should be grounded. I would love to get a rough drawing from you by email. I have spent many many hours researching this topic to include the ARRL recommendations. Yes some data from regular Hams but indeed also from electrical engineers, extra class operators, electrical code reference, and from some pretty big names in the world of amateur radio. The ending diagram showing how the shack is set up would have been a big help. I my humble thinking maybe we are missing a not yet marketed device that allows equipment to be grounded and like a lightening protector can separate the connection if high amperage is seen. Obviously a mechanical device could be employed. Hope to hear from you soon.
@@bassmanjr100 Thats says a lot about your interest in ham radio: so you only "using" it because other people are?! Thats what I like about the hobby : there can be interaction, with people, or building and experimentation or just observing and learning ......but with the "new types of hams" I don't think the longterm prospects are looking good.....but I don't think I will be here to see it.....
@@nul153 I posted my initial response . All I can add is, how many manufacturers of ham radio equipment put a ground lug on everything they make. Can that many companies be that misguided ? Hard to believe.
@@richardchandler9027 "how many manufacturers of ham radio equipment put a ground lug on everything they make" Nearly all of them I hope. The chassis is probably connected to the ground terminal of the electric outlet. Actually hooking up the ground lug on your equipment to a ground can create a "ground loop" which is not usually a good thing. Your radio might become the only actual path to earth ground for everything in your house.
@ That makes no sense to me. But then if the ARRl cannot agree on how it should be done why chance do we mortals have. There is absolutely no consensus on this subject. It is a crap shoot.
@@richardchandler9027 " There is absolutely no consensus on this subject. " Yes, there is. But a consensus among electrical engineers exists for a different purpose than it does for radio engineers. It is possible to accommodate both.
I was sceptical at the title, but watched anyway (i don't want to live my life in an echo chamber ... other opinions deserve air ... well, most do) ...
What a bloody interesting talk! Kristen's descriptions of her investigations (both theoretical and practical) are well presented, flow well and convey in layman's terms what's going on with with this very eclectic part of the hobby (radio and electrical).
Thumbs up to Kristen 👍 for what must have been a huge amount of work, for me to be able to watch for free, and to Hayden for bringing it out of the lecture theatre, so i could watch it whilst sitting in the comfort of my home eating lunch 🤜🤛
GND is simply a "point of reference" from which your measurement is taken. Nothing more, nothing less. Don't overthink the problem.
Floating ground? How do you measure if the electrical system isn't connected to the ground? 🤔 (From generation to consumption)
@@jamess1787 Example, a balanced transmission line has no "ground" where you can measure from, yet it has a theoretical ground which is the electrical difference between each side. This is true for many car audio systems as well. Telco circuits also do not have a ground per se. In an automobile that has a positive grounded battery (same for most of the 1960's germanium transistor AM pocket receivers) all the measuring points are of negative potential with respect to ground, so the "point of reference" still stands as to where you are measuring from. Ground is NOT zero volts ever and I think this is what the guest is trying to say, though she doesn't directly come out and say it. 73
@@WECB640 The ground wire going into the ground that is hooked up to the third prong in three prong outlets has zero voltage but that is a different kind of ground.
@@tom-hy1kn I respectfully disagree. That 3rd terminal may have an overall average that we conveniently label as "ground", but if you measure any point on it with respect to another point on the same wire, you will measure a difference in potential albeit small. This is because the wire has some minute value of resistance.
You are aware that there are electrical currents that are always traveling through the Earth below our feet. When lightning strikes or when a live mains cable contacts the ground, electricians know to hop away from the point of contact so that they do not have a difference of potential between their feet which could cause a current to flow up one leg and down the other thereby possibly causing death. The ground below is NEVER at zero potential between any two points. Even in a simple ham radio power supply, the current meter is usually measuring the voltage drop across a very low resistance in the ground (return) lead. So once again, ground even within the circuit of the appliance is never actually zero volts. We teach our students that ground is zero potential and we take great liberties in our textbooks to overly simplify this statement for the sake of simplicity, but it is technically incorrect. Unless the conductor has absolutely zero resistance (something not possible despite coming close in a liquid helium chilled superconductor) the internal resistance brings rise to a delta of voltage whenever a current flows. That is Ohms Law.
Touch an improperly electrified and ungrounded appliance (sarcasm) and get back to me.
Touch a properly grounded one when your feet's are not at the same ground and come back to me.
An excellent dissertation by an educated speaker.
Informative presentation. I need to watch it about three more times now. :)
Please do!
Great video, I really enjoyed it 👍
Thanks Ape!
@ nah son, thank you 🍻
@@TheSmokinApe Big hands
This is the fourth time I've seen this presentation, and it got me thinking instead of sticking to dogma.
As I prep my UA-cam channel and start laying the groundwork (no pun intended) for content, this is exactly the kind of topic I want to explore. There’s a lot of confusion around "grounding," as well money and effort wasted. I think it’s time we all take a step back and recognize that what we’re really talking about is a localized safety solution, not some universal law. The more we understand that, the better we can appreciate the role grounding plays in our electrical systems-and the better we’ll be at designing safer, more reliable systems in the future.
This is a draft of my first script. I will include the references at the bottom. I like this Lady!
Introduction
I’ve spent my career working with electricity and electronics-mostly hands-on, a mix of trade school and self-taught, with a degree from the school of hard knocks. Along the way, I’ve learned a lot of things that aren't covered in textbooks, but one thing's certain: in electrical systems, grounding is real-you can’t run a "safe", functional system without it. The problem comes when we start talking about "ground" as if it’s some kind of universal, unchanging reference point. The more you dig into the fundamental nature of electricity, the more you realize that "ground" as a concept becomes less clear when you move from practical, everyday electrical work to the world of theoretical physics.
I wrote a deep dive paper into the concept of "ground." While it’s crucial in electrical systems and it serves a very real, practical function, its absolute meaning starts to get murky when you apply the term beyond the world of circuits and into fundamental physics. We’ll be challenging the Dunning-Kruger effect by questioning the myth of ground-the idea of a fixed, unchanging reference point in the universe-and rethinking some of the ideas that get thrown around in both engineering and physics.
The Role of Ground in Electrical Systems
In practical terms, "ground" serves a very simple "function": it provides a low-resistance path for electrical current to return to Earth, especially during a fault or short circuit. If something goes wrong in an electrical system-say, a wire comes loose and touches a metal casing-the current needs somewhere to go. Grounding directs that current safely into the Earth, preventing shocks or fires. It’s a safety mechanism, plain and simple.
Now, here’s where it gets interesting. While "ground" is essential, it’s not the perfect electrical sink many people assume it is. When it comes to grounding electrical systems, a common misconception is that the Earth itself is a perfect conductor, capable of instantly absorbing and dissipating electrical energy. In reality, this idea is far from the truth. The Earth, in its purest form, is actually a poor conductor of electricity. This is because the Earth’s composition-primarily consisting of rock, soil, and water-offers considerable resistance to the flow of electrical current. This resistance can vary dramatically depending on local conditions such as soil type, moisture levels, and temperature. In fact, if the soil is dry or rocky, grounding can become much less effective.
So, why do we still use the Earth as a grounding point? The answer lies in the field around the Earth-not the Earth itself. While the Earth may be a poor conductor, the electric field that surrounds it is far more significant when it comes to the flow of electrical charge. (This concept is for a different podcast) The Earth’s resistivity is not uniform-it changes based on soil type, moisture levels, and other environmental factors. So when we talk about the Earth as a "ground," it’s important to remember it’s not an infinite, catch-all sink for electricity. In fact, its ability to absorb current is not unlimited. Grounding, as we know it in the field, is more about providing a path of least impedance, not about dumping all the energy into the Earth.
The Misleading Associations of Ground
Here’s where the confusion sets in. The word "ground" carries a lot of misleading connotations-especially when we start thinking about it as something more than it really is. The two biggest misconceptions about "ground" are:
1. Ground as Zero Voltage:
In electrical systems, we often refer to "ground" as a point of "zero volts." It’s the reference against which we measure other voltages. But let’s be real: zero volts is relative. There’s no universal "zero" across the universe. The voltage at ground is simply a reference point within the system you’re working with. Outside that context, the concept of "zero" becomes meaningless.
2. Ground as the Ultimate Sink for Electricity:
The Earth is sometimes treated as the "ultimate sink" for electrical charge-like a vast, infinite reservoir waiting to absorb all the current that comes its way. But the truth is, the Earth has resistance, and its capacity to absorb current is far from limitless. The effectiveness of grounding depends on local factors-soil type, moisture content, depth of grounding rods, etc. So, calling Earth the "ultimate ground" isn’t quite the full story.
These misconceptions lead to a misunderstanding of the true role of ground. Grounding is a "localized safety measure" within electrical systems, not an absolute, universal principle.
Grounding and Relativity in Physics
When we step out of the electrical engineering world and into the realm of theoretical physics, the whole idea of "ground" as an absolute reference point falls apart. Take Einstein’s theory of relativity as an example. According to relativity, there is no universal frame of reference-everything is relative. So, when we talk about "ground" as though it’s fixed and unchanging, we’re ignoring the fact that the concept of a "reference point" changes depending on where you are and who you ask.
For example, someone standing on Earth might think of the surface as "ground," but for an astronaut in orbit, their concept of ground would be entirely different. The idea of a universal "zero point" or absolute ground simply doesn’t hold up across different frames of reference. And in the realm of quantum mechanics, where particles and fields are inherently uncertain and fluctuating, the notion of a fixed ground is even more problematic. In these contexts, "ground" becomes a relative term, just like any other reference point.
Practical Grounding in Electrical Engineering
Now, back to the practical side of things. Despite all this theoretical discussion, grounding is still crucial in electrical systems. You need ground to make sure that your electrical system is "safe". The ground path is a circuit we design and build providing that essential path for current to flow back to Earth in the event of a fault, ensuring that dangerous currents are safely dissipated. But it’s important to recognize that "ground" in electrical systems is a "localized safety feature" we built and labeled, rather than an absolute, universal principle. When you ground a system, you’re not tapping into some infinite reservoir of energy; you’re creating a safe return path for fault currents. The grounding system typically connects to the Earth’s surface (or another conductive body), but the goal is always the same: direct stray current away from people and equipment, preventing shocks and fires.
Conclusion
To sum it up: "ground" is a critical part of electrical systems. Without it, our circuits wouldn’t function “safely”. But the concept of ground as some sort of fixed, unchanging reference point-that’s a myth. In reality, grounding is a practical tool for managing fault currents and providing voltage references, but it is not an absolute, universal constant.
References
1. Alexander, C. K., & Sadiku, M. N. O. (2009). Fundamentals of Electric Circuits (5th ed.). McGraw-Hill.
A comprehensive textbook that covers the fundamental concepts of electrical circuits, including grounding and electrical safety.
2. Hewitt, P. G. (2012). Concepts of Physics (8th ed.). Addison-Wesley.
A classic physics textbook that introduces the basics of electrical circuits and grounding, along with discussions of reference frames in physics.
3. Griffiths, D. J. (2017). Introduction to Electrodynamics (4th ed.). Pearson.
A detailed text on electromagnetism that explains the behavior of electric fields, circuits, and the concept of grounding in electrical systems.
4. Einstein, A. (1915). The General Theory of Relativity. Annalen der Physik, 354(7), 769-822.
A foundational paper in modern physics, where Einstein establishes the theory of relativity, showing the relativity of motion and reference points.
5. Feynman, R. P., Leighton, R. B., & Sands, M. (2011). The Feynman Lectures on Physics (Vol. 2). Basic Books.
Finally, I've been thinking this the whole time. Wonderful factual presentation.
This is a much more scientific survey of my observations regarding ground ambiguities. Grounding potentials are nebulous and ground loops are elusive especially when crossed with any kind of inductive coupling. Flooding the zone with grounds is seldom a solution. Grounds are commonly lifted at the source in audio studios. I was surprised at the role of coax shield in feel lines of antenna systems and where common mode current might appear. You can know more and not think of everything.
I was hoping she would get into the "separate or do not separate" the analog circuit ground from the digital circuit ground in electronics. From what I've researched, analog circuit components should be kept to one side of the board, and digital to the other, but best practice is for them to both share the same ground plane (I think there is one stipulation where a certain frequency range plays a factor, and so shared ground in very minute circumstances should be avoided).
The importance of cable shielding, from my understanding should be seen as an extension of device shielding, as in, many devices are in a metal case acting as a faraday cage in many ways, if a cable that is plugged into the device is properly shielded then the faraday cage would be extended to the cable. She did go over isolation and shielding, but it's helped me to think of cable shielding as an extension of a device's faraday cage. Let's say I have a DB9 serial cable running from my radio to a serial port on my pc (because I'm old school I guess), if I wanted to ensure quality RS-232 signals where being passed for CAT control without picking up any RF and without having digital computer circuitry RFI bleed into the radio, I should use a serial cable with a metal DB9 connector that is connected to the shield of that cable as well as utilize ferrites either along the whole cable or just before connection points. This should get rid of any "cross talk".
The part I find confusing or more convoluted is that If all of the devices in your shack are connected together via their ground lug screws/terminals and a bus bar, and then from the bus bar to a ground rod, and then a ground rod every 8ft or 2.5ish meters all the way until you reach your service entry panel (mains electrical service panel) ground rod to connect to it as well, wouldn't that make for a more robust shielded system that ensures the insides of devices can do what they are supposed to without interference from other devices or things? Or, would connecting stuff in this way cause problems with RF being coupled to the ground wire messing with your antenna system and other such things? (I'm sure this would depend on distances/proximity and lengths of conductors) Or, is she just saying that it isn't necessary if you properly isolate equipment with baluns and cable shielding? Technically though, would or wouldn't it be better to have all device case shields be connected to same ground? What is the best thing? Not sure if "it depends" applies here. One thing must be better than the other, even if that thing is not absolutely necessary.
On a side tangent, why were electronics in the 80's/90's so much more heavily shielded than today's stuff (generally speaking)? Was it because they used larger noisier components? Is it because mostly everything is digital and low power now? (cheapo wall warts, inductive chargers, and capacitive touch lamps meat FCC standards apparently...?) And, what is with cheap USB cables? Everybody loves USB C, but finding a USB C cable that has actually been designed to spec, which also happens to be affordable, is not really a thing. (Apple makes a great cable, but it costs booku bucks). How feasible is it from an electrical engineering standpoint to actually be using USB C for everything anyway? I would really like an engineer to explain. Especially if a manufacturer could just use a different cable that is more affordable and typically can be found with better shielding that is built to a more uniformly adhered to standard. One example would be XLR cable, it tends to have far superior shielding than just an AUX audio cable (3.5mm) would that be the reason why keyer jacks on radios are 1/4"? Some are not, but usually that's a QRP thing, and not all 1/4" aux audio cable is shielded as good, but if you type XLR to 1/4" cable you will get the good stuff, and then just chop off the XLR end and direct wire to your paddle/ straight key.
Wonderful accurate presentation. This is often misunderstood.
I do think this is over complicating the matter. It’s only a myth if you think of ground or earth, as some universal and ubiquitous zero potential thing, and every time you see the word or symbol for ground or earth, that they are part of it. Does anyone think of it like that? Possibly but only people for whom it’s not actually relevant. I would think any electrician, electrical engineer, just about any other Engineer, amateur radio operator, and so on, understand that it’s nothing more than the side of the voltage supply not called positive.
I think gnd matters more when dealing with static charges or lightnings than RF. Well this begs question how a static charge can influence an equipment ? - Maybe it has something to do with the shape of a casing, where some sharp corners could lead to the E field gradient not being an uniform distribution or in case of mosfets they have insulated gate so in rare examples where the body is not connected to the source of a particular mosfet that may cause too much potential difference when charged statically semiconductor's body but not the gate since the gate's dielectric was in neutral charge state before. So maybe it is necessary to do some experiment on equipment with outside UV charging.
I found this very interesting. I do not run a ground for RF from my modest shack (upstairs).
I work all bands 6-80m with very low SWR and low noise.
I do have a MFJ-931 Artificial Ground, but I have never felt the need to use it. I may try it on the back of tthis presentation as it is just a tuner for a counterpoise.
Currently the only Counterpoise I run is directly under my EFRW.
Thanks for the video.
2E0GKF
I've worked 159 DXCC entities with my humble setup. Happy with that after one year on HF. I've learned loads about propogation working Digital that will serve me well in the future.
I don't get many problems with lightning, if there is a risk, I disconnect the antenna's or take them down.
Are there any dowsers here ?. I find that selecting house ground stake location has subtle but important effect on performance of A/V equipment in the house.
Anybody noticed change in RF rig performance according to earth stake location ?.
The effects of ground or earth varies from DC to White Light. It can be a conductor, attenuator or reflector, depending on frequency and distance relative to free space. RFI in the shack is a different matter. An antenna must be matched at its terminals to coax and located far enough away depending on power. Consider a high power broadcast station. Still, an important subject and there are many engineering level books free on the web.
I use a 6ft copper rod 5ft into the ground, if i take the ground wires of the radios I get interference especially on SWR receivers.
Its horses for courses. The trouble is a good long ground rod giving low resistance for a power installation, would have too much series inductance to be much good at RF. I suppose a clever clogs could tune it out with series capacitance, why bother though, a ground mat or radials are a lot easier to deal with.
18:43 actually if you take your dipole and the tree is too small, just let it hover over the ground and it still works fine. You need just one radial. For a low SWR about 30 cm worked fine for me on the 20 m band.
"Ground is a Myth!"
I'll go stand on it and see for myself. Anyway, at radio frequency, unless your radio is sitting on the ground, it isn't at ground potential.
Ground is not a myth, ground is the name of a concept to communicate about with each other. This video shows that ground is just not what Kristen McIntire thought it was before.
I want to emphasise what she says about lightning. That part IS most important to have a ground. Lightning could only strike once in 20 years in your area, but let these 20 years not give you the impression you don't need (earth)ground.
I think of ground (even dirt) as just one of the wires.
I’m learning 📚
I’m a British 🇬🇧 Foundation Licence holder M7EOM I would like to Thank you for teaching me this I’ve certainly taken on board what you’ve said thanks again Kristen
very well done de wb8idy in swansboro nc 73
You forgot one. It's a source and sink of unlimited free electrons. The Earth has zero net charge. Connecting to it neutralizes any positive or negative charges that might otherwise build up on conductors.
There are not unlimited free electrons, also the earth is actually negative in that it has a surplus of electrons. Connecting to it only bonds to earth (the ground) so you remove any potential difference between your thing and the earth
But it doesn't. When a highly negative cloud base edges over you but not over the power company transformer, the green ground and the white neutral (commonly connected in the main circuit breaker (US, I've read that Brits have a variety of systems)) your antenna shield can be at a different V than a grounded mast. Also, high current in the wiring can mess up neutral potential, as well as send voltage spikes about.
@@LarryAllenTonar If your coax shield is bonded to ground where it enters your shack like it is supposed to be then you wont have that problem. And if the ground didn't sink that charge, everything metallic would be at hundreds or thousands of volts of potential every time the wind blew or a thunderstorm wandered by.
Wait.....?
I thought they said to never,
" Daisy chain " ?
😳
Ground is a myth, I have known this for 50 plus years through experience
No ground here. Only the 3rd prong on the wall outlet. DX daily with 20 Whiskeys
So, you look up to see the sky at the North Pole, and you look down to see the sky at the South Pole. 😂 It's all relative.
Except when you stand on your head or being drunk. Indeed, it's all relative.
Ground is not a myth, ground is the name of a concept by which we communicate about it with each other.
Ground is only a myth if you want it to be. For instance if you're in a plane or on the space station .
Nah you reference the negative voltage.
Same with a car brother.
There is something very attractive about women speaking in super nerd.
its all sematics
rubbish, ground does make a difference!!!!!!!!!!!
cant listen to this absolute rubbish, its alays the americans who have the odd ideas...is that something to do with all the additives in the drinking water..?
Id love to hear your opinions on the matter but the video hasn't even been up long enough for either of us to have watched all of it yet
It’s a well known fact that viewers don’t watch the whole video before making rash comments.
That's not what she's saying.
Counter theory instead of some ignorant comments
Relax dude. 😂 You don't want to get the sad ham award.
And she is the vice president of ARRL ! ....ham radio is doomed!
Lets have your counter theory
@@jonniez62 What she states is not a theory but what I can say is ham radio is all about "radio" thus electromagnetic energy being radiated and this is very much affected by the ground effect, if she really wants to know more about the subject I can recommend the multitude of excellent publications by the ARRL, like chapter 3 of the ARRL antenna Book to start off with....
Maybe you could publish the new revised and recommended by ARRL best practice ham shack setup , to include where if any and all equipment should be grounded. I would love to get a rough drawing from you by email. I have spent many many hours researching this topic to include the ARRL recommendations. Yes some data from regular Hams but indeed also from electrical engineers, extra class operators, electrical code reference, and from some pretty big names in the world of amateur radio. The ending diagram showing how the shack is set up would have been a big help.
I my humble thinking maybe we are missing a not yet marketed device that allows equipment to be grounded and like a lightening protector can separate the connection if high amperage is seen. Obviously a mechanical device could be employed. Hope to hear from you soon.
Yep. Better sell you crap now and give up. Another 6 month and no one will be using it. 😂
@@bassmanjr100 Thats says a lot about your interest in ham radio: so you only "using" it because other people are?! Thats what I like about the hobby : there can be interaction, with people, or building and experimentation or just observing and learning ......but with the "new types of hams" I don't think the longterm prospects are looking good.....but I don't think I will be here to see it.....
So... Do I need to have ground and my radio connected to it?
Yup if only for GFI to work. Being a path to a different potential can be unpleasant if not deadly.
@@nul153 I posted my initial response . All I can add is, how many manufacturers of ham radio equipment put a ground lug on everything they make. Can that many companies be that misguided ? Hard to believe.
@@richardchandler9027 "how many manufacturers of ham radio equipment put a ground lug on everything they make"
Nearly all of them I hope. The chassis is probably connected to the ground terminal of the electric outlet. Actually hooking up the ground lug on your equipment to a ground can create a "ground loop" which is not usually a good thing. Your radio might become the only actual path to earth ground for everything in your house.
@ That makes no sense to me. But then if the ARRl cannot agree on how it should be done why chance do we mortals have. There is absolutely no consensus on this subject. It is a crap shoot.
@@richardchandler9027 " There is absolutely no consensus on this subject. "
Yes, there is. But a consensus among electrical engineers exists for a different purpose than it does for radio engineers. It is possible to accommodate both.