Although...it is going onto a 'read this soon' list, and I'm probably not alone in that. With these sorts of concise primer articles, have you considered providing a .pdf or .tex of the page?
I'm not the author, but in the case of .pdf, couldn't you just use a 'Print to PDF' solution? On Windows I've used PrimoPDF before, don't know what OS you use but guessing all the major platforms have something similar.
Yeah, good point, I guess there are already tons of existing solutions for that which wouldn't eat up the author's bandwidth; the modern web really has spoiled us with so many 1-click conveniences, huh?
Both Chrome and Firefox provide built-in print to PDF feature on Linux and Windows (possibly other OSes too, but I'm not sure). Just click Print and select "save as PDF" or "print to file". Chrome even allows removing the URLs and other metadata from headers and footers.
Great review as an embedded SW guy to nourish my EE background. Nicely peppered with practical tricks and techniques that are useful in the field. I enjoyed seeing the low-pass and high-pass filtered wave signatures along with the explanation of what the problem might be (long/close connections and broken traces, respectively).
Hey, I really enjoy your hardware work! Ever since finding your website over 5 years ago, I've been checking in regularly for new projects and updates. The highlight for me is probably your precision resin casting projects.
I've been learning about basic circuit design recently and realized that I don't have any clue how things relate to the underlying electrodynamics. Does anyone have some good textbook recommendations that derive things like Ohm's law and concepts of capacitance, etc, from first principles?
Ohm's law was not derived. It probably shouldn't be called a law either. Capacitance, etc. can be found in Introduction to Electrodynamics by Griffiths, which is a standard E&M college text.
The "first principles" part of E&M has some tricky math which can be mitigated by a well chosen problem domain. If you really want to dive into it, I hope you love (or learn to love) multi-variate calculus, linear algebra, and switching coordinate systems (cartesian, polar, spherical) multiple times to solve a problem.
Those are two very different things (Ohm's Law and Capacitance).
Capacitance is basically the relation between electric field and charge, whereas inductance is the relation between magnetic fields and currents. Those follow from fundamental equations, if you want a calculus intensive derivation from the "first principles" of Maxwell's Laws. Someone on this thread mentioned Griffiths, which is a good text, it's what I used in E&M undergrad. Wangsness has a good E&M text too I liked.
Ohm's Law is a macroscopic statistical mechanical Law that happens in bulk.
It can be derived from even some of the simplest electron models (eg the very simplistic Druude Model). Where it can be shown that the current density through a chunk of material is proportional to the applied electric field.
https://en.m.wikipedia.org/wiki/Drude_model
But it breaks down in smaller systems, where statistical averages don't hold (for example ballistic conductance in a nanowire). Or other systems when quantum mechanical effects will dominate (eg bandgap non-linearities of a PN Junction or Quantum Well, or how the bandgap of a semiconductor causes an increase of resistance at lower temperatures as opposed to decrease of resistance for metals).
I used to have a nice presentation of the latter on my old uni website called A Quick and Dirty Preview to Solid State Physics, but alas they disabled my old account after nearly a decade past graduatiOn. (Had to make the webpage for a class early in grad school, and it was linked by many other solid state physics classes interestingly).
I've only met one electrical engineer who ever knew about anything below the typical EE abstraction. Everyone still gets the job done without having a clue. It helps if you're doing RF design or very high frequency stuff and that's about it.
I'm another big fan. Watched your videos some years ago and it started me on a fairly intense electronics hobby. Your videos on op-amps and radio are simply brilliant. Thank you!!
This is awesome and great as a short-form resource. For years, my long-form (non-concise?) go-to book has been "The Art of Electronics" [0] by Paul Horowitz (and others depending on the edition). It has everything you need in a single reference book!
This is a great, but difficult very at the same time, book on electronics. It expects student to know trig, exponential functions, and a bit of Calculus.
Supposedly, at Harvard, students finish it in one semester. It doesn't seem possible, but who knows. There's always a back story of the supposed feats I have heard about Harvard students.
Anyway, everyone interested in electronics should have it as a reference. You can skip, but come back to chapters 5 (first half), 7,12, 13, 14, and maybe 15.
Put it this way, if you have mastered everything in this book, you should be able to sit for any EE exam. If you can visualize the topics--you are very, very smart, or have true grit. It's not light reading.
If your completely new to electronics, get to know the basic equations. Ohm's law is so important. Remembering VAR saved me so many times. (Vomit=Amps x Resistance). In some circles, they don't like using the word amps; they always use current. I'm not in those circles.
Another book I found helpful is Ashly's book Electrical Engineering 101 Everything you should have learned on school but didn't. (There's a need for more honest books like this.)
Learn how to wire a house too. I've known EE's who don't know how to wire a modern home, or it's straight from a older reference book. Know a little bit about commercial wiring too. It's not that complicated.
Writing this, reminds me I need to brush up on Electric Vechicles. I was looking at new cars for my mom, and realized I didn't know much about hybrid vechicles. And I refuse to do what the dealership mechanic said, "Oh---no one works on their vechicles anymore! They bring it right here" A sign in the Service Department read $270 hr. He also said know one pays in cash anymore. I walked off that lot with 20 grand still in my pocket.
All I though about on the way home is I can't belive the number of new cars on the road, and I don't like not being able to repair a new vechicle. I walked off that lot with $20 grand, and a Blue Book. If I had an employee that didn't close on a used car--he would be fired. I guess the economey is doing better than it feels. Sorry, about rambling on--kinda depressed.
Everyone wants to talk about the penitential energy and what-not. Though that is mostly pointless unless you grasp the first fundamental concept of voltage. Voltage is just simply the effort exerted by electromagnetic field on neighboring electrons.
As soon as you grasp that all definition of voltage relate to the real world of doing `work` eg... heating, moving then the concept of voltage of amps is a lot easier to understand.
I was taught the same, though I never liked the concept of elevation, water, ect... It easier for me to quantify it when it relates to the real world such as newton force or doing work. The other reason I never really liked the concept of elevation it means nothing if you dont have gravity that is constantly acting on a object.
"potential difference" seems to be the relative difference between the "EMF" of two conductors, which is analogous to pressure-difference and is the relevant factor wrt current, power, etc.
> Voltage is just simply the effort exerted by electromagnetic field on neighboring electrons.
That sounds like you are talking about the _electric field_, which is a vector field. Charged particles feel a force in the direction that the electric field is pointing. This is analogous to the gravitational force field (a vector field pointing towards the ground) and how objects with mass feel a force in this direction.
The electric field has a _potential_ [0] (called the _electric potential_), which is a scalar field. This is analogous to gravitational potential, which coincides with height.
_Voltage_ is the difference between the electric potentials of two points, for example the two leads of a resistor (or other circuit element).
Another very good source of information is the US Navy Electricity and Electronics Training Series (NEETS). https://maritime.org/doc/neets
Also towards the end of the parent directory check the "Electronics Technician" volumes and other interesting stuff on welding, repairing etc.
50 comments
[ 139 ms ] story [ 192 ms ] threadAlthough...it is going onto a 'read this soon' list, and I'm probably not alone in that. With these sorts of concise primer articles, have you considered providing a .pdf or .tex of the page?
I'm not the author, but in the case of .pdf, couldn't you just use a 'Print to PDF' solution? On Windows I've used PrimoPDF before, don't know what OS you use but guessing all the major platforms have something similar.
:-)
Another great reference is the Art of Electronics.
Tons a practical advice for selecting components and building circuits that is still relatively relevant even today.
https://news.ycombinator.com/item?id=9653898
Also, this looks like a really awesome primer!
[1] http://lcamtuf.coredump.cx/afl/
[2] http://lcamtuf.coredump.cx/gcnc/
[1] http://lcamtuf.coredump.cx/table/
[2] http://lcamtuf.coredump.cx/prep/
Difficult to see how you can really be just one human.
Nicolas Borubaki wrote in a very abstract and badly readable style. So: no.
The "first principles" part of E&M has some tricky math which can be mitigated by a well chosen problem domain. If you really want to dive into it, I hope you love (or learn to love) multi-variate calculus, linear algebra, and switching coordinate systems (cartesian, polar, spherical) multiple times to solve a problem.
Capacitance is basically the relation between electric field and charge, whereas inductance is the relation between magnetic fields and currents. Those follow from fundamental equations, if you want a calculus intensive derivation from the "first principles" of Maxwell's Laws. Someone on this thread mentioned Griffiths, which is a good text, it's what I used in E&M undergrad. Wangsness has a good E&M text too I liked.
Ohm's Law is a macroscopic statistical mechanical Law that happens in bulk.
It can be derived from even some of the simplest electron models (eg the very simplistic Druude Model). Where it can be shown that the current density through a chunk of material is proportional to the applied electric field. https://en.m.wikipedia.org/wiki/Drude_model
But it breaks down in smaller systems, where statistical averages don't hold (for example ballistic conductance in a nanowire). Or other systems when quantum mechanical effects will dominate (eg bandgap non-linearities of a PN Junction or Quantum Well, or how the bandgap of a semiconductor causes an increase of resistance at lower temperatures as opposed to decrease of resistance for metals).
I used to have a nice presentation of the latter on my old uni website called A Quick and Dirty Preview to Solid State Physics, but alas they disabled my old account after nearly a decade past graduatiOn. (Had to make the webpage for a class early in grad school, and it was linked by many other solid state physics classes interestingly).
It's about an hour's worth of material and it is very concise.
Also here in Youtube playlist format: http://www.youtube.com/watch?v=8gvJzrjwjds&list=PLzqS33DOPhJ...
Another great channel for electronics basics is TheGreatScott: https://www.youtube.com/channel/UC6mIxFTvXkWQVEHPsEdflzQ
[0] http://amzn.to/2iZfjbG
Supposedly, at Harvard, students finish it in one semester. It doesn't seem possible, but who knows. There's always a back story of the supposed feats I have heard about Harvard students.
Anyway, everyone interested in electronics should have it as a reference. You can skip, but come back to chapters 5 (first half), 7,12, 13, 14, and maybe 15.
Put it this way, if you have mastered everything in this book, you should be able to sit for any EE exam. If you can visualize the topics--you are very, very smart, or have true grit. It's not light reading.
If your completely new to electronics, get to know the basic equations. Ohm's law is so important. Remembering VAR saved me so many times. (Vomit=Amps x Resistance). In some circles, they don't like using the word amps; they always use current. I'm not in those circles.
Another book I found helpful is Ashly's book Electrical Engineering 101 Everything you should have learned on school but didn't. (There's a need for more honest books like this.)
Learn how to wire a house too. I've known EE's who don't know how to wire a modern home, or it's straight from a older reference book. Know a little bit about commercial wiring too. It's not that complicated.
Writing this, reminds me I need to brush up on Electric Vechicles. I was looking at new cars for my mom, and realized I didn't know much about hybrid vechicles. And I refuse to do what the dealership mechanic said, "Oh---no one works on their vechicles anymore! They bring it right here" A sign in the Service Department read $270 hr. He also said know one pays in cash anymore. I walked off that lot with 20 grand still in my pocket.
All I though about on the way home is I can't belive the number of new cars on the road, and I don't like not being able to repair a new vechicle. I walked off that lot with $20 grand, and a Blue Book. If I had an employee that didn't close on a used car--he would be fired. I guess the economey is doing better than it feels. Sorry, about rambling on--kinda depressed.
s/series/parallel/ ??
Everyone wants to talk about the penitential energy and what-not. Though that is mostly pointless unless you grasp the first fundamental concept of voltage. Voltage is just simply the effort exerted by electromagnetic field on neighboring electrons.
As soon as you grasp that all definition of voltage relate to the real world of doing `work` eg... heating, moving then the concept of voltage of amps is a lot easier to understand.
It's an analogy. That's how analogies work. I was hoping for some substantive reasons the analogy doesn't hold.
force on electrons is "EMF", https://en.wikipedia.org/wiki/Electromotive_force
This scan be measure in volts, or joules.
"potential difference" seems to be the relative difference between the "EMF" of two conductors, which is analogous to pressure-difference and is the relevant factor wrt current, power, etc.
That sounds like you are talking about the _electric field_, which is a vector field. Charged particles feel a force in the direction that the electric field is pointing. This is analogous to the gravitational force field (a vector field pointing towards the ground) and how objects with mass feel a force in this direction.
The electric field has a _potential_ [0] (called the _electric potential_), which is a scalar field. This is analogous to gravitational potential, which coincides with height.
_Voltage_ is the difference between the electric potentials of two points, for example the two leads of a resistor (or other circuit element).
[0] https://en.wikipedia.org/wiki/Scalar_potential