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Ask HN: What are some good resources to learn how electricity works?

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Re: Ask HN: What are some good resources to learn how electricity works?

#142

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.

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.

Re: Ask HN: What are some good resources to learn how electricity works?

#143

Earlier quoted context omitted.

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 s…

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 i…

> 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.

Re: Ask HN: What are some good resources to learn how electricity works?

#144
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...

Re: Ask HN: What are some good resources to learn how electricity works?

#145

Earlier quoted context omitted.

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 i…

> 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 abs…

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.

Re: Ask HN: What are some good resources to learn how electricity works?

#146
post #68

Earlier quoted context omitted.

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?

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.

Re: Ask HN: What are some good resources to learn how electricity works?

#147

Earlier quoted context omitted.

> 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 abs…

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 interacti…

> 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 is involved.

Re: Ask HN: What are some good resources to learn how electricity works?

#148
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...

Re: Ask HN: What are some good resources to learn how electricity works?

#149
post #135

Earlier quoted context omitted.

> 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 the…

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.

Re: Ask HN: What are some good resources to learn how electricity works?

#150
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.

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