Learning electronics, and psychology - Page 1
Forum section: electronics / general

author: woodchips
author_rank: Frequent Contributor
timestamp: July 03, 2016, 10:07:35 am
content: Apologies about the psychology bit, but it does seem both important and relevant.This has been prompted by reading a new book by Angela Duckworth, Grit. Basically the book says that if you you want to learn something, pretty well anything, then you have to put in effort, lots and lots of effort. There is a saying that you need 10,000 hours to master something. The book delves more deeply into exactly what those hours need to be spent doing.There is a continual stream of posts on the forum along the lines of I want to learn electronics. Each post gains a number of replies, of which I have contributed a few. The first thing that is immediately apparent is that none of these supposed learners actually seem to read all the other posts on the forum, about learning or anything else. The same questions come up every time.Why do you want to learn electronics?Want a job. So that is pretty definite, how much of your effort are you prepared to put into learning then?This seems to be the first stumbling block, not many prospective electronics engineers seem to claim that they own even one book. Easily fixed by looking on abebooks.co.uk, amazon, ebay etc. What books to buy?Almost anything, at only £1 or 2 each they are not exactly expensive. You will buy lots, most of which are not very good but there is normally one nugget in each book. I became interested in wind generators and started reading around electromagnetism, now have two books cases of books, about 200 or so. All been read.Next is to put this book learning to work. But how?This is where I diverge from most of the advice put on the forum. Without doubt you need a 2 channel oscilloscope with a triggered sweep and THREE (not two, there is a trigger channel as well) probes, ideally the switchable 10:1/1:1 but not essential, 10:1 will do. Other than the scope all you need is a bench PSU and a simple multimeter, analogue or digital doesn't matter. Because money is tight then an analogue scope is the one to go for, costing next to nothing. I tried to give away some but had no takers or interest, sort of says just how much real interest there is in learning to my mind.Not a digital scope, an analogue one. Why? Cheaper. Also no extraneous rubbish and clutter on the screen, just one or two wiggly green lines, simple. At the beginner level the facilities offered by the DSO just confuse, on screen readouts tell you nothing, look at the knobs. All you need is something about 10MHz, no faster, and you only need 10MHz to get a reasonably fast timebase, 500ns/cm, to explore the circuits.What to start with?This did take a considerable amount of thought, what to start with. Assuming you can get a triggered hum waveform on the scope by putting your finger on the probe then you can drive the scope. Why isn't the waveform a clean sinewave?A blocking oscillator.This is pretty well the simplest circuit you can have, has one transistor and some Rs, Cs and an L. It also provides a wide range of wonderful waveforms to look at and wonder about.The L can be almost anything, look for a small transformer out of an old transistor radio. Even some hand wound windings on a piece of ferrite core will work, but be careful of the phasing of the windings, don't forget the blocking oscillator is a heavily positive feedback circuit. If you struggle, persevere, in the end ask here and someone will help.Now that you have it running you can start learning.Replace the transistor with an OC71, this is PNP germanium from the early 60's. It is slow, looking at the waveforms you can see switching time, storage and all the other little parameters of a transistor. You have 2 traces, look at the waveforms in different places in the circuit, and at different timebase speeds. Risetimes, insert a 1 ohm resistor in the emitter and look at the current, likewise the base but you will need both channels as a differential input.Now replace with an OC44, this is faster, then an OC171 which is a VHF transistor, then a modern silicon PNP transistor.Now that several months have passed, and you really do understand positive feedback avalanche oscillators then you can find 2 or 3 identical transformers to allow you to wire up 2 identical circuits. This is why you have 2 traces, one oscillator using the OC71, the other using the OC44. Now look at the differences. Repeat with other transistors.Up until now you have learnt a lot, and it has cost really nothing but time, lots and lots of time, months of time. Probably spent more on graph paper copying the waveforms than on the scope. In fact buying a really high quality hardbound notebook, in the UK such as the Black & Red type, to keep all your notes in.Next project might be a multivibrator, with the various permutations such as triggered, Schmitt etc. Again it is all low frequncy stuff the simple scope is more than adequate. You might now need to consider a function generator to drive the multivibrator. If you still use the OC71 then you are never going to exceed the frequency abilities of the scope. And you still don't know enough to cope with the things that happen at multiple 10's of MHz, that is two years time.Good luck.

author: Kilrah
author_rank: Unknown
timestamp: July 03, 2016, 12:11:19 pm
content: Quote from: woodchips on July 03, 2016, 10:07:35 amI believe that's way too specific, and assumes the goal is becoming a master in a very specialised field... which may apply to a few highly trained people, but less and less to the general public.Nowadays I find you're better off having a modestly deep (i.e. enough to provide some services) understanding in a relatively wide variety of different fields rather than being God in a single narrow one. And as time/effort investment grows exponentially with the level you want to achieve you'll probably be able to make a better living spread over 10 different fields if you spend 1000h on each instead of spending 10k to be a master in a single given thing that may not exist anymore 10 years down the line... at which point you're in deep mess since that's all you know.There's a need for both and in the end it's mostly a personal preference thing... Don't follow what the book says, rather take it as one way to do things that may or may not suit you.Quote from: woodchips on July 03, 2016, 10:07:35 amI doubt anyone who chooses a field only for the job is going to be any successful, they won't have the patience / interest to read and understand those 200 books.If you do what really interests you you'll be able to drop 180 of those books and will refer to the other 20 only when there's one thing you're not sure about, and the job will come "by itself".

author: bitslice
author_rank: Frequent Contributor
timestamp: July 03, 2016, 01:04:07 pm
content: Quote from: woodchips on July 03, 2016, 10:07:35 amI'm wondering if it is a generational thing, as it's never occurred to me to askanyonefor help.I mean, what's the point? If I didn't understand something then I just wasn't reading enoughI can't recall ever asking anyone for advice on any topic, because the world is simply awash with information on how to do everything. Once that ability to learn is achieved, the rest is just doing it for yourself or finding someone who is better than you to do it (plastering comes to mind).

author: Kilrah
author_rank: Unknown
timestamp: July 03, 2016, 01:15:31 pm
content: I don't think it's generational, I've seen both self-learners and "assisted" people of all ages, it's just a question of nature I guess.I'm like you, for me we have all the tools to learn anything we need/want by ourselves nowadays and asking someone is kind of admitting my own failure of using the wealth of info I have around.Most seem not to work that way though, and don't even realize those tools exist and they have an option other than asking to be explained/trained by someone else directly, and that they are actually capable of understanding things by themselves.

author: Maxlor
author_rank: Frequent Contributor
timestamp: July 03, 2016, 01:52:38 pm
content: Why is it a problem if people start looking at electronics then lose interest after a while? If I only ever started things I was 100% sure I'd stick with, I'd never do anything new.

author: woodchips
author_rank: Frequent Contributor
timestamp: July 05, 2016, 02:15:28 pm
content: Oh well, not certain this information is of any use, but Farnell do a wide range of possible transformers, from pulse type at £1-2 to audio interdtage at £10+, if anyone wants them.

author: Seekonk
author_rank: Super Contributor
timestamp: July 05, 2016, 03:20:55 pm
content: I learned electronics as a kid. There was no internet. I read a lot and studied every schematic I could find, no mentors. I had my first job in electronics at 15 repairing electronic organs. This was 1965 when transistors were new. My brother had to drive me to house calls as I had no drivers license. I don't remember ever being stumped by a problem.Went to college before the age of political correctness. A physics professor would just stare at a student when a question was asked for a couple minutes and then would say....."You don't belong here". At the time I thought it was a little harsh. The reality was these students were not prepared and had not read the material for class. They wanted to be spoon fed the information and not do any work.The internet has made it easy to be really lazy. There is always someone who wants to show how smart they are and answer a question that could be easily looked up with a little effort.

author: rstofer
author_rank: Super Contributor
timestamp: July 05, 2016, 06:00:23 pm
content: We should probably nail down what "Learning electronics" means. It's one thing to wander through web sites looking for projects and quite another to learn the subject at an engineering level. Is the goal to learn for hobby purposes? If so, there are a LOT of resources out there. But if you want to practice engineering, there's a lot of work to do and, frankly, I don't see it getting done outside of a university environment.

author: lapm
author_rank: Frequent Contributor
timestamp: July 06, 2016, 01:09:27 pm
content: This 10.000 hour rule is usually missquotet. It comes from story that studied athletes in top of their game... meaning best of the best..Do you want to be next Jim Williams of analog electronics? Might take 10.000 hours of learning and practicing..Want to be just good at it? Takes lot less hours then 10.000...You can learn basics of anything in maybe few hundred hours at most.. After that its more practice and wonder peculiarities and more advanced features that didnt show up while learning basics..

author: hans
author_rank: Super Contributor
timestamp: July 07, 2016, 10:18:40 am
content: It can also be hard to become a master of a moving target.Sports can be pretty fixed in that aspect, in particular athletic sports IMO. There can be regulatory changes, but in essence it's about discipline, training, peak performance and mentality to be the best.As for "moving targets" I think engineering is probably one of the wildest fields, aside from science. Every week there are new parts with application specific features, higher level of integration and more memory for more complex applications. You could put in a lot of hours into "the job" to become a master in it, but I think it's equally important how quickly you can grasp at new subjects and adopt. If it takes you twice as long to learn a new subject as others, then that's a pretty hefty handicap (but not the end of the world; there is always someone who is smarter).