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Ask HN: What are some good resources to learn how electricity works?
472 points by farleykr 18 days ago | hide | past | favorite | 180 comments
I've tried several times to understand the vocabulary and concepts of electricity - basic things like volts, amps, resistance - but I'm not having much success with self-led study. Can anyone recommend any good videos, books, courses, etc.? Thank you.



I highly recommend the All About Circuits textbook: https://www.allaboutcircuits.com/textbook/

It starts from the very basics and builds up to quite complex circuits and their workings. It's an all-round great website, too.


Wow, I'm so happy to see this is the first result (the reason I came to comment.) I've tried and failed many times to pick up a fundamental, from the ground-up understanding of electronics and electrial theory. Forrest Mims' "Getting started in electronics" was good, but the All About Circuits text book had the depth and accessibility and I was looking for.

And it's free!


Mechatronics text books tend to be useful. They are written for mechanical engineers who intend to build circuits and software for mechanic-electronic systems. So they tend to have practical information for those who want to start building electronic circuits now, but have no electrical background.


Have any specific recommendations for a hobbyist and outsider to formal mechanical and electrical engineering disciplines? Thanks!


The one I use is Introduction to Mechatronics by Carryer Ohline and Kenny

It covers a lot. On the mechanical side it only covers actuators and control systems.


This is an incredible resource. Learned everything I needed to know for an IoT side project and more from the AAC book


That's a nice TOC!

Flipping through, I think the thyrister treatment is a bit weak, and I would ideally like to see more in terms of comm-sys, (like how NTSC works for analog/radio TV), but this looks solid.

TIL about a nice reference.

Thank you!


The Art of Electronics is also fantastic


I respectfully disagree with this comment. I banged my head against The Art of Electronics for years before discovering that the problem wasn't with me... but rather, it was just a very poor book for a learner.

It may be a great book for those who already have some grounding in the topic.


Please, don't disparage a book because you personally did not find it useful. I, personally, found it very useful and it was my most important learning resources at the beginning.

Exactly as you said, because I have already had some exposure to physics and to kind of modular systems (I am mathematician working as a developer) this was perfect resource for me.

Different people with different backgrounds learn in different ways and from different types of resources. It is wise to understand there is no single resource that is going to be best for everybody.


> Exactly as you said, because I have already had some exposure to physics and to kind of modular systems (I am mathematician working as a developer) this was perfect resource for me.

So you're saying they're correct that it's not a good book for a learner without some exposure to the fundamentals. But what's the disparagement you're referring to?


It is important to differentiate between exposure to fundamentals of electronics and physics.

I believe if you have never been exposed to engineering or another discipline that deals with complex systems (like designing software or mechanical systems) you have to learn to build systems from smaller components. This is where many beginners fail. Even though they can sort of understand what parts do they can't put them together because they don't think in systems. In that case you need something else than AoE.

On the other hand, if you have built complex things in another discipline you may find yourself very at home with AoE with no previous exposure to electronics. That's because you already know how to build systems from lego bricks, now you just need to learn new kinds of bricks and rules to put them together.


That's a good summary. The book was originally written for physics grad students who needed to build instrumentation for their experiments. So intended readers probably understand electromagnetic theory, but need to know how you do things with available parts. That's where it's really useful. I own copies of all three editions. Third Edition is on a shelf nearby.

A good place to start is to get one of the small Elenco electronics kits. The ones with a solderless breadboard. That will get you the basics. With a solderless breadboard, you can always buy and add more components. Much hobbyist electronics is done on solderless breadboards, especially Arduino stuff.

Once you understand E=IR and W=EI, you can size most components. Beyond that, use LTSpice.


This book ruined many hours of my childhood, when I was in high school. I read it. I didn't understand it. I reread it. I still didn't understand it. At the time, I didn't realize I needed to know basic differential equations, and I just felt dumb.

Then I went to college.

When I looked at it as a more mature engineer, I found it imprecise, sloppy, and also not very helpful. It doesn't embody good design practice, give a proper theoretical basis, and the choice of topics is random.

Many people love it, but I hate it.


Thank you this has been very consoling to read as someone who tried and failed many times with this book when I was young. I thought I was just not smart but now realize most people on the internet who get this stuff are not brilliant autodidacts, they are just educated adults. Even reading a datasheet which is so critical was out of my reach (or patience) without the math and vocab.


it's a fantastic reference book - not great for learning the fundamentals


this looks very good. do you know if there is a PDF version that contains the whole textbook? could not find it on the website


actually found the PDFs


PDFs are here [0]. They are legally free. [0] https://www.ibiblio.org/kuphaldt/electricCircuits/


Second that :-)


The Minecraft mod Electrical Age is surprisingly useful to (literally play around and) get a feel for things. It was originally designed to teach electrical engineers once upon a time. Currently it's been a bit gamified -sure-, but the core MNA solver is still there.

Still somewhat surprising to me, this kind of simulation actually does help. It turns out that you actually do pick up a lot of intuitive feel that can serve well in an industrial context. I guess no matter how much theory you study on, it's still really insightful to just blow up some circuits. ;-)

Note that Electrical age currently works with older versions of minecraft (1.7) , though a rewrite is in the works.

https://electrical-age.net/


Problem: there is a difference of velocity of understanding between guided experimentation vs study vs mentorship...

(Many fail and are put off to learning the subject whenthere is no person they personally know to guide them through speed bumps)


That's where Electrical Age comes in, at least when it comes to power systems, generation etc.

All the stuff you're learning is in a way directly useful, whereas try to get a steam turbine IRL for learning at home...


I'm on the opposite side of this question. I've offered to explain motorcycle charging systems in terms anyone can understand. My thought is to use the water flow analogy. Voltage => pressure. Current => flow volume. Resistance => constrictions in the system (or things where the water does work.) Flow at one point in the system must match flow in other parts except for places where water can accumulate (battery => pressure tank.)

My biggest issue is how to depict this in a format that I can share over Skype without putting in 80 hours of work. I might go with a series of pencil drawings and scan them in.

Are any of the suggested materials particularly suitable for this kind of presentation? This is intended to be a 20 minute or so presentation so I'm really just providing highlights. Points I want to get across include:

- Resistance anywhere in the circuit will cause problems. (e.g. bad ground connection.)

- Bad starting can be the result of a insufficient battery charge.

- Bad starting can be the result of high battery internal resistance.

- Bad starting can be the result of high resistance in the circuit.

- Operating with loads (e.g auxiliary lights and heated vest) that draw slightly more power than the charging system delivers can work for hours until the battery is discharged and the charging system no longer supports the loads. (DAMHIK!)

Thanks!

edit:formatting


Bad starting can also be a result of physical resistance in the engine, especially as temperatures fall below the normal operating range. When engines get cold enough they put enormous load on the starter motor which has to draw more amperage to compensate.

I think it's very important to teach people that moving electric charges, represented by current, result in magnetic forces, and that these magnetic forces are what cause motors to turn. And an alternator or generator reverses the relation by spinning a magnetic field to generate current, which is why it charges a battery.


>Bad starting can also be a result of physical resistance in the engine, especially as temperatures fall below the normal operating range.

Is that true? Low temperatures directly affect the maximum output current of the battery, but I don't think engine tolerances are such that the engine starts to effectively seize up below freezing.


Lubricants get thicker at lower temperatures.


Good points - I'll be sure to include.


I've got quite a lot of experience teaching electricity at a high school level, and I'm also a (relatively) newly qualified motorcyclist with a lot to learn. Maybe we could be of use to each other? If you'd like to get in touch, my email is in my HN profile.

The pressure analogy is a really good one; the problem is a lot of people don't understand water pressure any better than they understand electricity.


YouTube videos might work, if you want to reach a larger audience.

Or you could try streaming on Twitch (so that people can ask you questions as you explain stuff).


I recommend having a look at "Practical Electronics for Inventors" by Paul Scherz and Simon Monk. The book offers a very good introduction about the basics of electricity with many helpful illustrations, written in a down-to-earth style. In case you are interested in electronics, you will find that the book covers many intermediate/advanced topics such as operational amplifiers with lots of practical examples.


I came here to recommend the same book. It's not an easy book though to read from cover to cover though. I found it useful to try to understand a completed circuit design (say for a solar controller or something else I was interested in) and when I ran into something I didn't understand I'd then open up that book and read areas that were relevant.


Yes, I had the same experience and I use it in the same way. It's a great book to have on your bookshelf as it covers a lot of topics and the chapters are, iirc, fairly self-contained; but I never read it from cover to cover.


Yes, this is a good one! Wish I had it when I was an MIT undergrad.


If you want to begin with the basics then I highly recommend Khan Academy, starting with "Electric charge, field, and potential" [0], then "Circuits" [1], followed by "Electrical engineering" [2].

[0]: https://www.khanacademy.org/science/physics/electric-charge-...

[1]: https://www.khanacademy.org/science/physics/circuits-topic

[2]: https://www.khanacademy.org/science/electrical-engineering


I personally learned a lot from sparkfun's tutorials. The format is pretty digestible, there are some good videos, and it links out to a few other good resources as well.

https://learn.sparkfun.com/tutorials/where-do-i-start/all


I second this. Hobby focused content might seem amateur but it has some advantages in my mind.

Context: My biggest gripe with traditional education is lack of context for why a principle is important or useful. Not a problem when you are focused on a project.

Practicality: The practical aspects of theory are usually limited to core principles and help you see through the fog of all the details.

Narrative: Bringing many topics together in a project narrative give a linear path through the related principles which is less overwhelming.

https://hackaday.com articles, in my experience, have been a good jumping off point and often have solid links for better understanding.

A weakness of this approach is that it ignores the mathematical techniques to solving some of the problems. I doubt you will learn how to analyze circuits with differential equations or phasor analysis on a hobby site. That said, I rarely use these tools outside of an academic setting.

I'm sure someone will recommend The Art of Electronics. Its a great resource once you have the basics under your belt, but hard to use as a learning tool without prior knowledge. It touches on a lot of details by presenting a circuit and summarizing key points about its operation.

Once you have a handle on the basics I highly recommend playing with some circuits in a simulator. LTSpice is free and very high quality. There are other online options too.

You can experiment on hardware relatively safely if you stay away from high voltages and currents (avoid mains power and car batteries, always use circuit protection such as fuses). You will be frustrated if you have no test equipment though, a multimeter is a must-have.


Sparkfun and Adafruit schematics are a great source for learning, too. I designed an I/O shield (with optoisolated inputs and relay outputs) with their open source hardware as the main learning material, and I was delighted that it passed the review of an experienced EE!


First, it is important to distinguish between electricity and electronics.

The difference is like being physicist and mechanic. Do you want to be physicist and understand electricity as a phenomena or do you want to be an engineer and use it for something useful. Believe me, there is less overlap than you think.

One good resource I have found is series of articles on http://amasci.com/ele-edu.html which mixes a little bit of both worlds.

Have fun!


Engineers should understand the underlying physics plus know how to use it for something useful. There are degrees such as "electrical engineering technology", which cut out the harder fundamentals (and advanced classes that require it) and just focus on things you can do with current technology. Such skills become obsolete faster as technology changes.


I'm not sure I completely agree with this: electronics refers specifically to (essentially) anything concerning the control/emission of electrons (so transistors, thermionic valves, etc.); it's not just "advanced electrical engineering".

The divide you're talking about exists in both electrical and electronic engineering, if they are to be considered separate disciplines: in electronic engineering you have both the solid state physics required to understand semiconductor devices, and the layers of abstraction used to design analogue circuitry; in electrical engineering you have all the theory of electromagnetism, and the layers of abstraction used to design electrical machines.

The divide you're referring to is real, but it definitely isn't the electrical/electronic divide.


Electronics is about building useful circuits. Do you really need to understand what precisely happens within any of the parts? No, not really. I can't imagine what happens to electrons in MOSFET nor do I care. For my purpose it represents some transfer function which is what I use to build the circuit. When I think about OpAmp, the physics is not one of things I am thinking. My mental model of OpAmp has no physics in it and it is about relation between input and output signals.

Think this way: do you need to understand how a complex IC part works? No, you don't. You read the manual and learn that if you put something on particular inputs you will get something on outputs. You leave designing the internals to others. You take parts other people built and solder them to long pieces to copper glued to PCBs.

That's really most of electronics.

You need to know a little bit of physics. You need to appreciate some phenomena like losses, noises, you need to know what happens at high frequencies, maybe you want to understand how heat is conducted away from your parts, etc. You need to know couple extremely simple formulae and laws (laughably simple to any physicist interested in the matter). Other than that your parts function as tiny little lego bricks that are transfer functions to affect how your circuit works.


> Electronics is about building useful circuits.

This is just factually inaccurate; electronics is the field which relates to control/emission of electrons.

If you build a "useful circuit" which does not use any active components, you aren't doing electronics.

If you're applying solid state physics to model transistor behaviour, you're doing electronics.

The terminology has absolutely nothing to do with levels of abstraction.

I understand what you're saying, and agree that there is a broad range of levels of abstraction within electronics, but the division in abstraction is unrelated to the division between electrical and electronic engineering.


There are multiple definitions of electronics. If you are physicist you might envision electronics as control of emission of electrons. If you are an actual engineer you will have very different definition and understanding of what electronics is.

It is like calling computer scientist experts in software development. No, knowledge of algorithms is far, far from software development which is also about human interaction, project organization, and many, many other things.

Go google "electronics definition":

>noun

>the branch of physics _and technology_ concerned with the design of circuits using transistors and microchips, and with the behaviour and movement of electrons in a semiconductor, conductor, vacuum, or gas.

So no, it is not obviously just about control/emission of electrons.


> the branch of physics _and technology_ concerned with the design of circuits using transistors and microchips, and with the behaviour and movement of electrons in a semiconductor, conductor, vacuum, or gas.

Yep; it is explicitly is talking about either active devices or literally cases where the topic of focus is control/behaviour of electrons.

> If you are physicist you might envision electronics as control of emission of electrons. If you are an actual engineer you will have very different definition and understanding of what electronics is.

It has nothing to do with the level of abstraction at which you're working, which is my entire point; whilst an engineer may very well not be considering the behaviour of electrons in day to day work, if she is doing electronics, she is working with devices/technologies which involve the control/emission of electrons. If she is working on, for example, an induction machine, she is not doing electronics.

Again, I'm not contesting that people work at different levels of abstraction within a field, just pointing out that the term "electronics" as opposed to "study of electricity" has absolutely nothing to do with abstraction; it refers specifically to whether <active devices/transistors/semiconductors/control and behaviour of electrons/whatever you want to call it> is involved.


EE degree here to back you up. I believe you're correct, electronics is to electricity what software engineering is to CS. It's the practical application with as little depth as you can get away with. For example there's some bits of RF you'll learn when you look at 45 vs 90° PCB traces, but you don't need finite-difference time domain equations to understand what's going on.


Exactly. I know enough physics and mathematics to know that what is used to create designs is laughably simplistic and oftentimes incorrect knowledge. But it doesn't matter, we are not pushing physics with the designs. We just want enough heuristics to be able to build something that works.

Electronics engineers don't go wielding equations to build circuits (well, except maybe Ohm's Law) but rather rely on intuitive models they have in their brains of what components do when put in a specific place in the circuits.

This is necessary shortcut because otherwise even simple circuit can become extremely difficult to understand if you start from first principles.


> electronics is to electricity what software engineering is to CS

I would respectfully disagree with this assertion.

I'm pretty sure my colleagues who are designing novel FinFET transistors for low noise applications are "doing electronics", and I'm also pretty certain that they're considering the underlying semi-conductor physics in some pretty serious depth; they're definitely not trying to work with "as little depth as [they] can get away with".

Electronics as a discipline encompasses people working at many levels of abstraction, including those working at a very low level. I think transistor designers would be very amused (or perhaps offended?) if you were to claim that they weren't doing "proper electronics" because they're actually thinking about things in depth in a very analytic way.


Oh I wouldn't ever claim component design is anything but complex. I was just trying to make a distinction between high-level fields and something like embedded hardware integration where you can treat each component as a "black box" of sorts and just care about I/O and operating characteristics. I don't mean to diminish your colleagues' work, it sounds fascinating.


Hmm. What level do you want to start from, and do you want to start from a practical/experimentalist viewpoint or go straight to the mathematical models?

How comfortable are you with "lies for children" oversimplifications of things that are extremely complicated but mostly irrelevant except in edge cases? (This phrase sounds perjorative but isn't, most of the time you don't need the complicated version and it actively impairs understanding what's going on. But it can be the only way to properly answer some questions like "what is electricity?")

I've occasionally considered writing my own, based on answering questions at electronics stackexchange, e.g. https://electronics.stackexchange.com/questions/245610/is-vo... / https://electronics.stackexchange.com/questions/272694/how-d... ; probably I would target explaining how the electron is a big source of "lies to children", and mostly an irrelevant distraction for beginner/intermediate work.

If you want a large book, The Art Of Electronics is the undisputed classic.


I just want to weigh in and say that fantastic as _The Art of Electronics_ is, it is _not_ geared for learning about electricity and electric circuits. The first 13-ish pages (3rd edition) deals with electricity and then quickly moves on to signals, electronics and everything else needed to _develop_ electronic systems.


I think you're wrong, mainly because learning how to develop electronic systems is, in my opinion (and also in the opinion of the authors of that book), the best way to learn how electricity actually works.


There is no reason to be so absolute about it. I'm not saying it is a bad book or that you should read "Field and Wave Electromagnetics" before you ever dare touch a multimeter.

As an example of my reasoning. AoE and the Arduino starter kit cost roughly the same in my country. They are of course not comparable, but I'd would definitely recommend the latter to someone completely new to electronics, exactly because the latter gives the tools for experimenting.


I agree with you. I have a degree in electrical engineering and use that book to quickly remind myself how something that I haven't used in a long time works and get an overview of practical do's and don'ts. If I had tried learning the basics of electrical circuits from it, I think I'd become discouraged very quickly.


It was pretty much my introduction to circuits, and had it not been used in a class with a significant lab component I would have also been discouraged. Great reference, but not good for teaching yourself unless you're very comfortable being confused or have had prior exposure to the material.


While AoE (and the newly released X-Chapters!) is an excellent handbook to keep around, I would agree with the other commenters that it is not a particularly friendly textbook for a beginner.


I got a lot from the articles on amasci.com by Bill Beaty. He's done a lot of experimenting, reading, and thinking about this stuff and how to explain it. And is a gifted communicator.

Articles on Electricity http://amasci.com/ele-edu.html

Great essays on understanding electricity, current, voltage, capacitors, transistors, batteries, static electricity etc etc, and popular misconceptions.


Bill’s “What Is Electricity?” essay [1] was discussed on HN two weeks ago [2].

[1]: http://amasci.com/miscon/whatis.html

[2]: https://news.ycombinator.com/item?id=23442181


Thanks thanks thanks, I read the article about why three prongs long ago. Every now and then I want to say the same article to someone else but did not remember where I read it.

There is also one about different types of plugs in Europe and UK which I cannot find


Yes, he is quite a wonderful teacher.

One of my favorites: http://amasci.com/amateur/whygnd.html


Walter Lewin's electromagnetism course from MIT [0]. These lectures completely transformed my understanding of physics. He mixes practical demonstration with a rigorous mathematical underpinning in a way that doesn't over simplify things.

[0] https://m.youtube.com/playlist?list=PLyQSN7X0ro2314mKyUiOILa...


+1 for Walter Lewin's explanations. I also can't say enough about the clarity of explanations and examples in Feynman's Lectures [1] and the HyperPhysics [2] tutorials.

[1] https://www.feynmanlectures.caltech.edu/II_toc.html

[2] http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html


I would add also the whole Feynman's Vol I

https://www.feynmanlectures.caltech.edu/I_toc.html

I believe one can't appreciate the whole subject enough without knowing that the electromagnetic forces are how the atoms "work", also producing "chemistry" and everything we see.

To paraphrase Feynman, the electromagnetic forces also keep you from falling down through the floor.

For the start:

"If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generations of creatures, what statement would contain the most information in the fewest words? I believe it is the atomic hypothesis (or the atomic fact, or whatever you wish to call it) that all things are made of atoms—little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another. In that one sentence, you will see, there is an enormous amount of information about the world, if just a little imagination and thinking are applied."


I'm showing my age here, but I got my start with the series of books by Forrest Mims that were available in Radio Shack stores since the 70s. They are written to be understood by complete novices, and they have hand-drawn circuits with everything explained.

http://www.forrestmims.org/publications.html


Did anyone else have a "rest of the fucking owl" experience in the first few pages of those books? It was like: Step 1. Here is a resistor. Now, Step 2 here is an AM radio circuit.


That's how I feel every time I try to learn how to use APIs. All the tutorials are like "Here's what REST means" and then "Ok so here's JSON, but we're not telling you what we typed in to get this or what to do with it".


Holy moly, I had these too. My parents had them in their library, I read them growing up in the 90s. I haven't read them since then, but I do have fond memories of them. It's not like basic electronics has changed since they were written, and I imagine you can get them for real cheap today.


This book really helped me, as well.


Hyperphysics presents a organized tree-like view of concepts, terminology and examples. It's easy to click around and start building up a mental model of how things relate: http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html


This page was a staple of mine during my physics degree, and also during my PhD when I was teaching these concepts


I love that site! They’ve got a lot of neat stuff on holograms too.


There is a basic circuits course upcoming in HackadayU, which is targeted at newbies and is pay-as-you-wish. https://hackaday.com/2020/06/17/schools-in-session-with-hack...

Just another resource that may help! You'll have no shortage of perspectives and approaches from the links here.


I remember in high school I had trouble getting it because I thought ohms law had too many variables. Then I realized that a 5V supply will always be 5V in normal operation and ohms law means the current varies.

All of the water analogies were unhelpful for me. I did better just doing the math and seeing the result.

Someone else mentioned MITx. I did that and it was revolutionary. I also have a pretty good book called Practical Electronics for Inventors.


> Then I realized that a 5V supply will always be 5V in normal operation and ohms law means the current varies.

This is a great observation. I've often thought that teaching Ohms law as I=V/R would lead to less confusion. Similarly, in intro physics why is mass acceleration introduced as f=ma? Wouldn't a=f/m have a clearer meaning?


I agree, that’s my preferred form as well. That’s because Ohm’s law is an empirical law, which states that current is proportional to voltage. It’s the definition of resistance, and it’s not always valid.


Division is hard!


It becomes infinitely more clear and simple to understand when you stop thinking in terms of "A equals F divided by M" and think of it as "A equals the ratio of F to M".


It also is infinitely more clear and simple to understand when you correctly realize that "F equals M times A" instead. I assume this was just an accidental transposition and you're not actually a crackpot. :)


Doh!


Also, don’t get hung up on electrons moving opposite the current. It’s not a big deal for most applications.


> All of the water analogies were unhelpful for me

Same here, I just had to come to accept that there were orthogonal dimensions/measurements. It didn't matter if I understood them intuitively, as long as I worked with them orthogonally and in strict accordance with the basic equations.


Try ElectroBOOM channel on YouTube: https://www.youtube.com/user/msadaghd


I'm genuinely amazed he's not been found burned to a crisp in his workspace. The same goes for Photonic Induction, how he's not burned down his street, let alone his house is a miracle:

https://www.youtube.com/user/Photonvids/videos


That's how you know he actually knows what he's doing: he knows precisely how to shock himself for comedic effect without causing any damage.


This, most of the dangerous mistakes are just gags.

IIRC Mehdi admitted on reddit that the one time he really screwed up and was genuinely scared was when the Jacob's Ladder fell on him[0].

[0] - https://youtu.be/lT3vGaOLWqE?t=467


He also has a nice playlist[0] called 'ElectroBOOM101' where he teaches the basics.

[0]: https://www.youtube.com/playlist?list=PLr_CZLgMkHeWFl1uf5yR2...


= Geared a little more towards mechanical engineering, but Jeremy Fielding on YouTube has helped me understand some of the concepts with examples rather than textbooks. https://m.youtube.com/channel/UC_SLthyNX_ivd-dmsFgmJVg

= For straight up electric concepts, I’d look at the Georgia Institute of Technology stuff on Coursera. “Introduction to Engineering Mechanics” and “Linear Circuits 1” were helpful.


The training program offered by the US Navy is quite good. Because they can only have so many people on a ship, the Navy tries not to be as specialized as the other services. So, electronic techs are expected to have especially good foundational knowledge so they can work on a broad variety of equipment.

https://www.fcctests.com/neets/Neets.htm


I enjoyed MITx circuits and electronics.

They've moved everything around since I did it, but I think this is the one: https://courses.edx.org/courses/course-v1:MITx+6.002x_6x+1T2...


Nobody seems to have mentioned a book that appeared here 19 days ago.

[Letters of a Radio-Engineer to His Son (1922)]((https://news.ycombinator.com/item?id=23358380)). It explains electricity without any technical jargon. Pretty nice first read. His atomic model is outdated, but that doesn't seem to interfere with anything. After reading the first initial letters, you might have a greater motivation to dive into more complicated texts.


You might find the Navy Electricity and Electronics Training Series helpful: https://www.fcctests.com/neets/Neets.htm


The Art of Electronics is perhaps the best textbook (in any subject) that I have read. I’d highly recommend it. It’s exceedingly pragmatic and will discuss a mix of physical underpinnings as well as applications.


I found the book "Practical Electronics for Investors" by Paul Scherz [0] to be one of the better ones.

My problem with learning electronics, and, to a lesser extent, electricity, was that most of the guides gave an 'ad-hoc' approach, giving "rules of thumb", recipes, etc. without really going into the reasons for it. They would start off with an (imo) overly technical explanation of quantum effects, then jump the more fundamental Ohm's law, etc., then jump into all the tips-n-tricks of circuit design.

For me, the two major factors to learning electronics were getting enough math sophistication that I could do calculus and linear algebra and being able to program (microcontrollers). The calculus and linear algebra gives tools for the 'passive' analysis and once you realize that most 'practical' electronics nowadays are basically routing power and signal, being able to program is the "meat" of it.

After understanding how to do passive steady-state circuit analysis, I briefly looked at how to do non-passive simulation (transistors, etc.) just to see how it was done (aka, learned how SPICE et. all do it).

Anyway, I found the "Practical Electronics for Inventors" book to be one of the few books that was practical from the outset and actually went into the theory, even if only briefly, without assuming I would get frightened by complex numbers.

There's obviously a path that doesn't involve calculus, linear algebra and programming, because people do it and have been doing it for many years, but these were the tools that helped me understand.

I would also recommend not doing this in the abstract. Arduino's [1] are, in my opinion, one of the better places to start. You can get an LED blinking within 5 minutes of onboxing. Adafruit [2] has many tutorial but they're more focused on using pre-built modules and I guess programming, to a lesser extent, than underlying theory.

[0] https://www.amazon.com/Practical-Electronics-Inventors-Fourt...

[1] https://store.arduino.cc/usa/arduino-uno-rev3

[2] https://learn.adafruit.com/


I wrote this a long time ago, when I was a teacher, which might be a good starting point.

https://www.bournetoinvent.com/projects/7-SC-Torch/pages/1_L...

(please excuse the crappy JS)

On another note, I would avoid the water in pipes analogy, as it fails pretty quickly. Electricity is hard to understand because you can't see its effects clearly, but at the end of the day it is caused by an electromagnetic field. Other fields such as gravitational fields, we tend to have a much more intuitive understanding of. Look for explanations that draw parallels between gravitational fields and electromagnetic fields.


I would suggest things that use the hydraulics analogy, like this: https://ece.uwaterloo.ca/~dwharder/Analogy/


I would probably recommend this. Thinking of electricity as analogous to water flow under gravity can get you a long way. I do recommend studying the mathematics of imaginary numbers (not hard, just takes a bit of time) since this is used for AC circuits and this is the tool that makes that stuff make sense.

When you get to active (transistors, diodes etc) devices don't spend much time trying to figure out the physics of these things just use the equations and keep it simple. Just as when you're cooking eggs in the morning it doesn't help much to understand prospecting, mining and metallurgy to use the frying pan.


I'm (early) in the process of writing Ultimate Electronics Book [1], which has interactive simulations built in. It was discussed extensively here on HN 4 months ago [2].

Take a look and let me know what you think.

[1] https://ultimateelectronicsbook.com/

[2] https://news.ycombinator.com/item?id=22315899


Along with a book (lots of good recommendations to choose from here), I recommend getting yourself some basic tools for practical experimentation: breadboard, multimeter (even a cheap Chinesium model will be fine for low voltage DC work), an oscilloscope (entry level DSO models from Chinese OEMs such as Siglent and Rigol can be had very affordably), a bench power supply (Siglent and Rigol also offer these), and some components (Joe Knows kits that are sold on Amazon are a great way to stock up on decent quality resistors, capacitors, and semiconductors to help you get to building circuits).

If you get to wanting to experiment with faster circuits, you can ditch breadboards and their parasitics for Manhattan style construction[1] and be able to build _much_ faster circuits with better success. Or you can fall down another rabbit hole, learning how to design your own PCBs. With PCB services becoming mainstream nowadays, you can learn a tool such as KiCad (free software) and send out your gerbers to be manufactured for cheap.

[1]: http://www.sdmakersguild.org/the-art-of-manhattan-style-circ...


I'm the solo dev on an industrial training website. We have a short lesson about the basic electrical units (voltage, current, resistance) that might serve as an approachable introduction or handy reference: https://www.lunchboxsessions.com/materials/basic-electrical-...


Your site is really amazing. Well done! I was a mechanical engineer for a bit and it's fun going through your lessons and reacquainting myself with that world.


I recommend the book "Make: Electronics 2nd Edition"

I knew nothing before starting the book and knew enough by about halfway through to start pursuing my own projects.


I like that his book is hands-on right from the start, and immediately defuses one's fear of electricity with exercises such as touching a battery to your tongue, blowing a fuse, and burning out an LED.


The ARRL Handbook for Radio Amateurs explains electricity and electronics for the beginner, and you might also get an interesting introduction to radio, too.


Yep. And ham radio is both an interesting hobby in its own right, and one place where you can build, experiment with, and learn about all sorts of electrical and electronic concepts. I can't recommend highly enough getting a Technician class ham license (the test is super easy with a little bit of study and only costs something like $15.00), a cheap dual band transceiver (I use a Baofeng HT), an RTL-SDR "dongle", and starting to explore the world of radio.


Many of the older editions are free on archive.org.


Which is a copyright violation, no doubt...

I highly recommended "Every Circuit" it's a fun little electronics simulator which helps you to understand different electrical components and their interactions

https://play.google.com/store/apps/details?id=com.everycircu...


I second this view with this old full circuit simulator: https://www.falstad.com/circuit/

The default example here is the LCR-circuit which to understand mathematically requires a bit of work https://en.wikipedia.org/wiki/RLC_circuit


I found the „Hello world from scratch“[1] series from Ben Eater incredibly helpful in connecting the dots between electricity and modern computers. Strictly speaking it is about electronics, still it is superbly presented and incredibly enlightening when coming from „normal“ software engineering perspective of things.

What actually got me there was the book „Code“ by Charles Petzold[2] which traces the development from early circuitry like light bulbs and telegraph wires to modern digital logic. I found that after being introduced to these concepts, learning about the fundamental physics was much more accessible since it was framed in the context of contemporary application.

1: https://youtu.be/LnzuMJLZRdU

2: https://www.amazon.com/Code-Language-Computer-Hardware-Softw...


I like Tony Khuphaldt books. Simple but effective. The letter to radio engineer's son were super nice IMO (https://www.gutenberg.org/files/30688/30688-h/30688-h.htm)

don't forget googles and gloves


I am going through this Udemy course with my kid and it's really enjoyable. The instructor is clear and really enjoys the topic:

https://www.udemy.com/course/analog-electronics-robotics-lea...


Before you try to understand electricity try to understand work and energy. Know the definition for a watt and what that means mechanically for example.

For really basic things: maxewels equations, ohms law, and the idea that in a closed system potential and kinetic energy are constant. Just grab a university level physics book.

V=IR (ohms law) gives you most of what you need for DC circuits. Remember that power is volts x amps so you can exchange one for the other (for free in an ideal world.)

Alternatively if you want a practical understanding here’s what I learned from as a kid: forest mim’s book (it’s wrong in some ways but it works) the art of electronics (this has anything you could want to know and is well organized and written, like an O’Reilly book for electronics in general) and this really old book I found in a used book store titled “introduction to pulse circuits.”


I would stay away from Maxwell's equations unless doing something to which they're truly relevant (designing an antenna or something I guess, maybe building a rail gun if you're into that). Maybe I'm blinded by the years I spent as a computational electrodynamics researcher but the model is a little heavyweight for your standard hobby project.

That said I really like your suggestion of starting with basic mechanics and thermodynamics. "Resistors get hot, motors do work, and capaciductors are like springs" goes a long way to tie everything else together


Sure capacitors are like springs, but I'd say inductors are more like flywheels.


Many folks have successfully used the US Navy training modules for electrical systems: http://www.compatt.com/Tutorials/NEETS/NEETS.html


Have a look at https://lcamtuf.coredump.cx/electronics/

It's from the developer of AFL and the Guerilla Guide to CNC. Check out the root domain for lots more interesting stuff.


Not sure if it's generally applicable but I've learned a lot from reading and trying to understand how the circuits here work.

https://ludens.cl/Electron/Electron.html


I enjoyed "There are No Electrons: Electronics for Earthlings" by Kenn Amdahl. It's a light hearted take in the form of a silly story, but it explains things surprisingly well.

Guess I should add that it covers the basics of electricity and the basics of electronics.



this is something different, does army have any more such guides?



This is an anecdote but I hope it helps someone. I couldn't understand electronics for the longest time. I read all about the individual components and I understood them individually, but I still couldn't grasp what they did when put together. Digital circuits made perfect sense to me though. Finally I learned about the "LRC" circuit. When you put those 3 components together, you can understand their behavior with some equations. You can dial in some coefficients to get the behavior (the signal/wave) that you desire. I don't know how someone thought to put those components together into a unit originally though.


https://wiredthegame.com/ is a free video game that is designed to give an understanding of how electricity works. It's probably worth playing through.


Outside of electricity fundamentals, this book is a great intro on how the grid works: https://www.amazon.com/Electric-System-Nonelectrical-Profess...

Or a shorter alternative: https://www.ucsusa.org/resources/how-electricity-grid-works


I bought this book on this recommendation and I don't agree that it should be called great. It did a good job of enumerating (what I presume to be) every major component of power systems. However, it didn't to a great job of explaining how any of those components work.

One example is capacitor banks, which it spent a few pages on. I'm told that they're more beneficial the closer to an inductive load they're installed, but I was never told why, or given any tools to figure it out why for myself. There's not even a citation.

After reading this book I have a better understanding of how much of the grid I don't understand, but I don't feel like there's any part I understand particularly better.


For the basics of how electricity works (as well as for an in depth understanding) my recommendation is Electricity 1-7. It's a textbook originally published in 1966, so it doesn't cover anything digital, just good old analog electricity.

https://www.amazon.com/Electricity-One-Seven-Harry-Mileaf/dp...


I experienced the same issue when I was in college. I discovered that the way to learn for me was to find a niche category of projects and do them on my own. I actually wrote a blog post about it a while back: https://burakkanber.com/blog/how-i-taught-myself-electronics...


Big fan of the No-Nonsense Technician-Class License Study Guide. In addition to vocabulary and terms, there's also sections about units and conversions and basic maths involved to understand the flow of electrical current as it passes through a system

https://www.kb6nu.com/study-guides/


Try "Code: The Hidden Language of Computer Hardware and Software." It provides a very simple introduction to electricity. Beyond that, it's just a great introductory book on computing.

https://www.amazon.com/Code-Language-Computer-Hardware-Softw...


I absolutely love this book, but I'd say it's more an intro to computing (like you said) than electricity. Electricity is in there, but IIRC it doesn't go much further than the "water analogy" style of thinking about electricity.


I originally learned electricity from Isaac Asimov's understanding physics, volume 2 when I was 13(?). I don't remember the details, but it clearly worked and helped me in all future education.

If you want to try and learn some basics, and then try apply them, both AoE (mentioned already by pjc50) and "Practical Electronics for Inventors" are good choices.

The latter is much more affordable than AoE.


Not affiliated in any way, just found it enjoyable, an Android game called Circuit Jam was a really fun way to refresh some basics for me.


I studied mechanical engineering in college, but we had to take a single EE course that made my head spin. What helped me a lot was the "hydraulic analogy": https://en.wikipedia.org/wiki/Hydraulic_analogy

Still tricky to apply it to AC though.


Although, not exactly what you're hoping for, there's a good documentary on the history of electricity called "Shock and Awe - The Story of Electricty".

It sometimes helps me understand better if I get some context on things, how people were thinking before it was discovered, what kinds of hyptothesis and experiments led to another and such.


I had an electronics learning lab from radio shack and loved the hands on aspects. https://www.amazon.com/RadioShack-28-280-Electronics-Learnin...

You can still find them on ebay, or similar kits if you look around.


I had these as a kid but in reality at the time I think I was too young to understand the details of what was going on. Many of the components I would accidentally attach a large battery to and let the magic smoke out. I do miss Radio Shack though.


I wanted to add one more thing. You mentioned volts and amps. Try to think of them as units of measure. This helped me:

1 watt = 1 volt times 1 amp. So a watt is a volt-amp.

Similarly to how 1 joule is a newton-meter per second.

When you work with units of measure symbolically in this way, you don't need to worry about not having an intuitive grasp of a joule or a newton.


The Manga Guide to Electricity is great! Plenty of non trivial introductory textbook level material.

https://www.amazon.com/Manga-Guide-Electricity-Kazuhiro-Fuji...

The whole Manga Guide to X series is great.


Watching Youtube videos of real people trying electrical builds (wiring a shed, van, new house, etc), then reading the comments by real electricians telling them all the places they've messed up and aren't to code has actually been a very good learning experience for me.


Best way to understand volts vs amps is a gravity analogy. Pulling electrons away from protons takes energy, and stores it, the same way that taking basketballs to the top of a cliff does. The voltage is the height of the cliff. The amps is how many basketballs per second you're dropping.


Øyvind Nydal Dahl has lots of good resources on his website and mailing list.

https://www.build-electronic-circuits.com/category/basic-ele...

His mailing list is high quality but also high volume


Eugene Khutoryansky's youtube channel is great for understanding electrical concepts as well as a bunch of other math and physics concepts

https://www.youtube.com/watch?v=ukBFPrXiKWA&t=1s


I recommend MIT 8.02 - Electricity and Magnetism taught by Walter Lewin [1].

[1] https://www.youtube.com/watch?v=rtlJoXxlSFE&list=PLyQSN7X0ro...


Follow-up question: How do I safely experiment and play with my newfound amature electrical knowledge?


I'm a musician, so my inroad to safely playing with electronics was circuit bending. You can buy kid's toy pianos and soundmakers and such for effectively $0 at thrift stores. Unscrew the casing, crack it open, pop in fresh batteries, get the thing making some its sounds and then.... start bridging together different locations on the circuit board and see what the effect is! I've often been amazed what sort of beautiful, otherworldly tones you can pull out of something that would otherwise be seen as near-garbage. Because it's battery-powered, the risk of shock is really low. It's a way to play with circuitry without inhaling a bunch of solder fumes. It's fun to do with kids. You can do it with pretty much any circuit that makes sound (even those greeting cards that play music when you open them). Lastly, there are a ton of resources online if you aren't quite sure what to do — the term is "circuit bending", it's great, have fun!


Stay with low power. (Low tension and low intensity.)


How? Use batteries only?

Obviously I shouldn't plug my own creations directly into the wall. Is it safe to use a low voltage "power brick"? Will any do, or do I need an especially robust one just in case?


Power bricks should be fine. I'd suggest starting out with a pretty low voltage (5, maybe up to 9), in DC.

Keep in mind though, that while these voltages are generally below the threshold required to conduct through skin, and represent little shock hazard, pretty much any electrical system can be hazardous in other ways.

In particular, you can create a fire hazard even with pretty low voltages, if the resistance is low enough and your power supply is capable of providing enough current. Likewise for sparks: if, FSM forbid, you happen to have some explosive vapors around (and even a bottle of fingernail polish remover can be a source of explosive vapors), a small spark can start a fire.

My point isn't to try to scare you off, but rather to say that you always need to be cautious, pay attention to what you're doing, and keep safety in mind, even when playing with low voltages.


The nice thing about batteries is that you can add them up to whatever voltage you need. Common electronics voltages are 5V, 9V, 12V, 18V, 24V. You can achieve all of these with different numbers of rechargeable AA or 9V batteries.

However, because of the variety of projects you'll do, to use a wall power source you'll need either a variety of adapters of different voltages, or one of those expensive multi-voltage power adapters, or a proper bench power supply.

So, yes, one of those 5V or 9V wall adapters is perfectly fine to use. You simply buy the female portion of the adapter and connect it to your circuit. However, if you do end up exploring multiple projects early on, using batteries will reduce the amount of new expensive gear you need to buy.


As a kid I played with batteries and wall bricks or wall warts or whatever you call them(transformers). I would not say you need an especially robust one. They come in different sizes based on the amount of voltage they output and the potential current they can supply. Basically if you are playing with a 9 volt battery and want to replace it with a transformer just look for one that says 9v DC output on it.


There are people who say things like its not the voltage that kills its the current but through the human body under normal conditions it takes a decent bit of voltage to induce enough current to really hurt you. Watch out for things with large capacitors and large voltages. If you want to take something like that a part let it sit for a long time for the capacitors to discharge. I worked at a TV repair shop in high school dismantling tube TVs for scrap components. The first step after opening was to use a large screwdriver to discharge the flyback transformer.


> Watch out for things with large capacitors and large voltages.

Oh man I have some retrocomputing equipment I really want to play with but I'm a little worried as there's a huge capacitor, some of the wires coming off the power supply manual are visibly old and to add to it, one of the first pages in the maintenance manual is a CPR guide.


I would not say you need an especially robust one. They come in different sizes based on the amount of voltage they output and the potential current they can supply.

They're also typically really cheap, which can be an advantage if you fry one. Or two. Or ten. Not that I'm speaking from experience or anything. :-)

Seriously though, if you have any kind of thrift store, surplus store, or something of that nature near you, you can often pick up random wall warts for next to nothing.


I recommend playing with 5V, many Arduinos and microcontrollers run on that, or have a voltage converter that allows them to accept it. And this means you can use a stripped USB cable from a standard usb wall plug to power your projects.


I'm just going to put my two cents in and say if you start learning on "electron flow" materials instead of "conventional current" materials you'll have a much easier time understanding how just about every electronic component works.


I found this tutorial to be extremely accessible http://developer.wildernesslabs.co/Hardware/Tutorials/Electr...


I’ve enjoyed Make: Electronics from O‘Reilly. I think it’s a good mix of theory and experimentation.

https://www.makershed.com/products/make-electronics-2ed


I am a researcher working in the the field of charge transport, electric current, material conductivity etc. I am happy to help you understand concepts and answer any of your questions as much as I can. Please don't hesitate to contact me.


The 'hydraulic analogy' can help with basic intuition about the terms - https://en.wikipedia.org/wiki/Hydraulic_analogy


Old videos but they are clear, entertaining, and still my favorite: https://www.youtube.com/user/acmeschool/videos


The Story of Electricity - BBC Documentary FullHD 1080p

https://www.youtube.com/watch?v=NUUeGianTKM

Its sn excellent 3 hour documentary on how electricity was discovered.


just watched it last week. hence increased curiosity about this thread..


MIT 6.002 course, by Prof. Anant Agarwal. Videos are on youtube. Absolutely fantastic!


http://amasci.com/ele-edu.html

Great resource, which dispels a lot of myths and misused terminology in many other traditional explanations. Fun read!


What are you trying with self left study, and why do you want to learn?

These are important questions.


I recommend the videos at this channel. Start with the basics.

https://www.youtube.com/channel/UCk0fGHsCEzGig-rSzkfCjMw


Pirate Electronics[1] was a nice resource I backed on Kickstarter years ago.

[1] https://pirateselectronics.teachable.com/


You should get a breadboard, some components and a 5v power supply. Work through some problems in Practical Electronics for Inventors 3rd Edition. A scope would be nice, but a DMM would suffice.


The Demystified series of books is pretty good - lots of examples, with exercises and quizzes. On the topic, the series includes Electricity Demystified and Electronics Demystified by S.Gibilisco.


The Engineering Mindset has lots of good videos with nice examples - https://theengineeringmindset.com


There's a ton of content on YouTube that covers this topic.

For example I did a search for ohm's law class 11 and that search finds pages of introductory videos on that topic.


Take a look at these articles - they start with first principles:

http://amasci.com/ele-edu.html


This is the best resource I found that really explain what this whole electricity stuff is. I spent years at in engineering programs and none explain as well as it is by William.


Is there a good game where you build circuits and simulate them to accomplish various tasks?

I'd love something like shenzhen io but with more emphasis on circuits than signals


Electric Power Systems; A Conceptual Introduction by Alexandra Von Meier is a very informative book.


What worked for me was enrolling in Electronics 101 at my local community college.


Manga guide to electricity is a cute read!


Electroboom!

YouTube guy. Funny and does electronics basics.


MITx Circuits & Electronics [1][2][3] (it's in 3 parts) MOOC. They are just starting a new instance today, so your timing is perfect.

This is a seriously good course. I've been interested in electronics on and off since I was a kid. I tried learning from various Radio Shack books, but never got very far. I tried some introductory classes at Caltech, and never got very far. Tried "The Art of Electronics" and it just didn't work.

That MITx course worked.

That said, it does get fairly mathematical...circuits involving inductance and capacitance are going to be analyzed using differential equations so if you have never had any exposure to such things it could be rough going.

If you've been through college calculus you should be fine, even if (like me) you've forgotten most of it. They have some refresher material that should bring enough back to get through it.

Here's what you learn in part 1:

• How to design and analyze circuits using the node method, superposition, and the Thevenin method

• How to employ lumped circuit models and abstraction to simplify circuit analysis

• How to use intuition to solve circuits

• Construction of simple digital gates using MOSFET transistors

• Measurement of circuit variables using tools such as virtual oscilloscopes, virtual multimeters, and virtual signal generators

Part 2 teaches:

• How to build amplifiers using MOSFETs

• How to use intuition to describe the approximate time and frequency behavior of first-order circuits containing energy storage elements like capacitors and inductors

• The relationship between the mathematical representation of first-order circuit behavior and corresponding real-life effects

• How to improve the speed of digital circuits

• Measurement of circuit variables using tools such as virtual oscilloscopes, virtual multimeters, and virtual signal generators

• How to compare the measurements with the behavior predicted by mathematical models and explain the discrepancies

Part 3:

• How to construct and analyze filters using capacitors and inductors

• How to use intuition to describe the approximate time and frequency behavior of second-order circuits containing energy storage elements (capacitors and inductors)

• The relationship between the mathematical representation of first-order circuit behavior and corresponding real-life effects

• Circuits applications using op-amps

• Measurement of circuit variables using tools such as virtual oscilloscopes, virtual multimeters, and virtual signal generators

• How to compare the measurements with the behavior predicted by mathematical models and explain the discrepancies

The first course is 4 weeks:

Week 1: From physics to electrical engineering; lumped abstraction, KVL, KCL, intuitive simplification techniques, nodal analysis

Week 2: Linearity, superposition, Thevenin & Norton methods, digital abstraction, digital logic, combinational gates

Week 3: MOSFET switch, MOSFET switch models, nonlinear resistors, nonlinear networks

Week 4: Small signal analysis, small signal circuit model, dependent sources

The second course is also 4 weeks:

Week 1: Amplifiers, MOSFET large signal analysis, MOSFET small signal analysis

Week 2: Capacitors, first-order RC circuits

Week 3: Inductors, first-order step response, first-order circuit analysis, impulses, digital circuit speed

Week 4: Impulse, step, ramp superposition, digital memory, state, ZIR, ZSR

The third is 6 weeks:

Week 1: Second-order circuits, damping in second-order systems

Week 2: Sinusoidal steady state analysis, frequency response, frequency response plots, impedance methods

Week 3: Filters, quality factor, time and frequency domain responses

Week 4: Op-amp abstraction, negative feedback, Op-amp amplifiers, Op-amp filters and other circuits

Week 5: Stability, positive feedback, oscillators, energy and power

Week 6: CMOS digital logic, breaking, the abstraction barrier

[1] https://www.edx.org/course/circuits-and-electronics-1-basic-...

[2] https://www.edx.org/course/circuits-and-electronics-2-amplif...

[3] https://www.edx.org/course/circuits-and-electronics-3-applic...


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