Where to find beginner projects - Page 1
Forum section: electronics / beginners

author: lieinking
author_rank: Newbie
timestamp: February 10, 2019, 09:48:20 pm
content: I've been sick so I'm not working. I decided to do this as a hobby and am learning mainly from allaboutcircuits.com. My problem is I can't find beginner projects easy enough for me. I've mad a simple circuit with an LED but the next simplest circuit I found is a flashing LED which uses a 555 timer. There's no explanation other than a schematic. Every other online project I see is more difficult. I'm looking for projects that walk you through holding your hand. Where Can I find the simplest projects with good guidance?

author: Wimberleytech
author_rank: Super Contributor
timestamp: February 10, 2019, 10:11:34 pm
content: https://www.forrestmims.com/

author: Zero999
author_rank: Super Contributor
timestamp: February 10, 2019, 10:23:35 pm
content: Quote from: Wimberleytech on February 10, 2019, 10:11:34 pmBe warned, his books contain some fun errors. Here's a classic one. Assuming both LEDs are equal, LED 1 will never turn on, unless you count the tiny current through the base of Q1. A simple fix could be to make LED 1 red (low Vf) and LED 2 green (higher Vf) (assuming the saturation voltage of Q1 is low enough for it to work) or put a diode in series with it. This would have been an ideal opportunity to explain diode voltage drops and give an example of them being useful.And "Do not subsitute the '339"? WTF? There are only two comparators used. Substitute it for the LM393. I suspect what he meant was, use a comparator IC with an open collector output. Do not substituent with an op-amp IC which has a push-pull output. A short paragraph explaining the difference between open collector and push-pull outputs and ORing would have been a good idea.

author: rstofer
author_rank: Super Contributor
timestamp: February 10, 2019, 10:54:33 pm
content: Take that astable (blinking) 555 LED project and beat it to death with a club! A short definition of astable: Always changing state. not stable in either the on or off state.You can start by building the circuit as given in the description of a project and then research the astable 555 configurationHere's a simple calculator you can use to verify what you see with the various component valueshttp://www.ohmslawcalculator.com/555-astable-calculatorHere is a Wiki re: the operation of the chip itself:https://en.wikipedia.org/wiki/555_timer_IC#AstableIt is worth knowing how the 555 operates and it is a pretty easy circuit to learn. A capacitor charges up and at some point along the capacitor voltage curve, the internal flip-fflop changes state. The capacitor then discharges and at some point on the way down, the flip-flop changes back again.Plan to spend some time with the circuit, chip description and calculator. As a first project, it is going to take a while to really understand what's going on. The more or less advanced math in the Wiki doesn't help. Use the calculator...Maybe a regular datasheet will help:http://www.ti.com/lit/ds/symlink/lm555.pdfSkim it at first just to find out where various subjects are covered. Then see how the pin description lines up with the circuit you built. Try to figure out what the circuit does with the various pins. Look at page 10 where astable operation is covered. Note that RLis shown in two configurations: The dashed load resistor uses the timer to provide ground to the load that is already connected to Vcc on one end. The plain RLis set up for the 555 to provide Vcc to a load that has one side grounded. Either will work. In fact, I think you can substitute a resistor and LED for both RLconfigurations. I don't know what voltage you are operating at but if I were doing this with 5V Vcc, I would probably use something like a 470 Ohm resistor and a standard Red LED. At 12V, I might try 1K. Neither configuration is going to overdrive the LED. Or use what your circuit shows.If you spend a solid day playing with the circuit, changing resistor and capacitor values, reading through the documentation and just reflecting on what you see, you will learn a lot.Then tie a monostable 555 to the output of an astable 555. This allows you to define a particular pulse width with the monostable that is independent of the operating frequency of the astable. Within limits, of course.Revisit the project when you get a scope. There is a lot to learn about the capacitor charging voltage that is overlooked in the first pass and, while easy to describe mathematically, really jumps out when you see the capacitor voltage versus output level changes. Then you will really understand the magic!

author: Wimberleytech
author_rank: Super Contributor
timestamp: February 10, 2019, 10:58:41 pm
content: Quote from: Zero999 on February 10, 2019, 10:23:35 pmLOL...yup.As an author of a technical book...I can appreciate errors. This one seems egregious, however.

author: Wimberleytech
author_rank: Super Contributor
timestamp: February 10, 2019, 11:09:23 pm
content: Quote from: lieinking on February 10, 2019, 09:48:20 pmOr build and analyze this:https://shop.evilmadscientist.com/productsmenu/tinykitlist/652

author: rstofer
author_rank: Super Contributor
timestamp: February 10, 2019, 11:14:28 pm
content: But the hand printing is excellent! I only wish I could write like that.Sometimes I wonder about this hobby! How does somebody start from scratch? I mean really 'scratch'. I look at "The Art of Electronics" and the companion "Learning the Art of Electronics" and I think I shake my head. Is this really the lowest common denominator?Maybe somebody should write the Errata for the Forrest Mims books.There are many tutorials on the Web including the EE program at Khan Academy and "Real Analog" at Digilent but even these make assumptions about math and much of that isn't necessary for beginners.I don't have any of the Mims books but between the "Getting Started In Electronics" and the Mini Notebooks, there seems to be quite a bit of material. I suppose one approach is to build the experiment and if doesn't work, post it at EEVblog. Somebody will know how to fix it.

author: Wimberleytech
author_rank: Super Contributor
timestamp: February 10, 2019, 11:26:58 pm
content: Quote from: rstofer on February 10, 2019, 11:14:28 pmWhen I was a kid...there was no internet, but there was Popular Electronics. A lot of things I tried did not work...but a few of them did. I joined a book club that sent me books on electronics...95% over my head...but it was inspiration.

author: rstofer
author_rank: Super Contributor
timestamp: February 10, 2019, 11:28:26 pm
content: Maybe a useful exercise is to explore Ohm's Law. It is clearly the most fundamental and important of all the laws of electronics (from a beginner's point of view, I don't want to talk about Maxwell).Get a battery and a resistor (say 1k just to prevent overloading the battery), connect the battery + terminal to the DMM red lead, the DMM black lead to one end of the resistor and the other end of the resistor to the battery - terminal. Make sure the meter is set up to measure mA before making the battery connections. Given, say, a 9V battery, we would expect to see 9 mA (give or take).Then put another 1k in series and we expect to see the current drop to 4.5 mA. Take out the meter and connect the circuit as battery + to one end of one resistor, the other end to one end of the second resistor and the final resistor lead to the battery - terminal (a simple series circuit). Now measure the voltage across each resistor. Should be about half the battery voltage. A voltage divider. Replace the lower resistor with a 470 Ohm resistor and the voltage across it will be about 1/3 the battery voltage. About 2/3 will be dropped across the 1k resistor in this configuration.There's a lot to learn just playing with a few resistors and a battery. Among other things, it provides experience with a DMM.Prove that E = I * R for example 9V = 9 mA * 1000 Ohms. For a 1.5V battery: 1.5V = 1.5 mA * 1000 Ohms. The resistance is given, the current is measured, the voltage is calculated. OR, the voltage is given, the resistance is given, calculate the current.Do it enough that you can do it in your sleep! Use lots of different values.Maybe this helps:https://en.wikipedia.org/wiki/Voltage_divider

author: sokoloff
author_rank: Super Contributor
timestamp: February 10, 2019, 11:33:07 pm
content: If you're interested in getting some basic projects knocked together, buy an Arduino (clones are fine) and an Arduino starter kit and play around.Lots of things you can learn and amuse yourself with starting there. It's not going to teach you much (anything?) about analog electronics, but it might get you enough motivation and dopamine rewards from seeing things work that will give you motivation to figure out some of the analog stuff along the way.Do a YouTube search on "Arduino" and watch away. That'll give you an idea if you want to plunk down the $50 or so to get a good starter kit or not.

author: rstofer
author_rank: Super Contributor
timestamp: February 11, 2019, 02:00:23 am
content: Everything that can possibly be done with an Arduino has been done and the project is on the Internet.It's debatable whether these projects teach anything about electronics, and in my view they don't, because all the experimenter has to do is copy and paste. But success is almost guaranteed if the project is copied correctly so that's really a good thing. Success is good!What it does require is C or C++ programming skills if the project is going beyond copy and paste. That's not a bad thing because embedded programming and IoT are currently the 'shiny objects'. Programming skills will be handy.In any event, it's a worthwhile start and, as mentioned above, can provide a lot of motivation to explore in the analog end of the sandbox.The problem with the conventional approach to teaching electronics is that it takes a couple of years of theory before things get interesting and it's hard to stay motivated. Better to start by building things and learning along the way.The good news is EEVblog, almost any question can be answered by somebody around here.

author: Wimberleytech
author_rank: Super Contributor
timestamp: February 11, 2019, 02:25:11 am
content: Quote from: rstofer on February 11, 2019, 02:00:23 amYup...there is nothing new under the sun. But arduinos are fun.Oh, my...I think I am a poet.There is nothing more motivating than to do something (even if it is not original) and see it work in front of you.I enjoyed every step of my formal education...well...I hated the motors lab...too damn scary...prolly dont even teach that any more.

author: nick_d
author_rank: Regular Contributor
timestamp: February 11, 2019, 02:25:22 am
content: The fundamental problem with starting from scratch in electronics is that it is quite a technical subject. Study pure maths for a couple of years so that you understand about solving differential equations, and then encounter an R/C circuit, and you will be quite well equipped to understand how it works. Similarly, complex analysis and AC.However, it is seldom learned in that order. Indeed you probably have to play with R/C circuits or AC circuits a bit to motivate why you should learn that difficult maths in the first place.So with this chicken and egg situation, the problem facing a beginner is where to start. You just have to jump in and try to build something. You won't get it fully the first try. But each project highlights your current weaknesses and helps you decide what to study or build next.In response to OP's concrete question: if the course says build a 555 timer but only gives a bare circuit and no explanation then either (1) decide not to build a 555 timer and find another course or (2) decide to build a 555 timer and find additional resources on it.cheers, Nick

author: rstofer
author_rank: Super Contributor
timestamp: February 11, 2019, 03:04:38 am
content: Quote from: nick_d on February 11, 2019, 02:25:22 amI realize that I am as bad as anyone around here for harping on the math. In a typical community college curriculum, you would have had Calc II and be taking Differential Equations concurrently when you hit your first circuits class. Worse yet, there's a year long Pre-Calc course that will be required of all except the High School AP students. Not so much required as a pre-requisite if the skills exist but required in the sense that you are unlikely to succeed in Calc I without the skills. Calculus isn't hard, it's the Pre-Calc that will kill you.And yet, I manage to play with electronics at some level with only Ohm's Law and perhaps Kirchhoff's Laws and a basic understanding of datasheets for op amps and transistors. I'm not designing space going hardware and nothing I do will break new ground. I just play with stuff.Yes, I probably have the math skills and the school thing but, really, I don't use that stuff very often. I like to play with Arduinos and, more probably, ARM processors. I really like to design logic circuits so, more often than not, I'm working with FPGAs. But, even there, math isn't much of a requirement.Find circuits that are interesting, build them and see how it works out. If it fails, no problem, try again! Or post the circuit and a description of the problem on EEVblog.You can't do much with the hobby with NO math but a little Algebra (and darn little) along with Ohm's Law and you can go quite a long way. Given resources like Khan Academy, the math thing is pretty easy to learn. And they have an EE curriculum as well.We just need to separate out the hobby part of electronics from the technician and engineering parts.Arduinos are fun! Robotics is interesting without necessarily requiring advanced skills. Check outhttps://www.pololu.com/

author: alex.martinez
author_rank: Contributor
timestamp: February 11, 2019, 09:11:07 am
content: Quote from: lieinking on February 10, 2019, 09:48:20 pm555 times are relatively easy if you understand how the IC works internally (and this why it is called 555 timer). Here you have an explanatory video about the 555 timer.https://youtu.be/i0SNb__dkYIAs to where find detailed projects, I recommend you start with YouTube channels like GreatScott! or similar. The projects they feature are relatively easy and interesting while being well explained, conceptually that is.

author: Zero999
author_rank: Super Contributor
timestamp: February 11, 2019, 11:16:00 am
content: Quote from: alex.martinez on February 11, 2019, 09:11:07 amIn my opinion the 555 is not a very beginner friendly IC. It's good in that it's easy to grasp the internal workings. The main downside is it has the nasty habit of drawing large current spikes from the power supply. Proper supply decoupling is mandatory. Careful attention should also be paid to the layout, with the decoupling capacitor near to pins 1 and 8 and the time delay capacitor as close to pin 7 as possible. A common beginner error is just slapping it on a breadboard and expecting it to work.The CMOS versions such as the ICM7555, TS555 and TLC555 are much more forgiving than the old NE555 and SE555. They do have their disadvantages, compared to the traditional 555: more ESD sensitive and weaker output stage, but that's more than made up for by the advantages: wider supply voltage range (2V to 18V, rather than 4.5V to 16V), lower bias currents & higher input impedance, therefore capable of using larger timing resistors and longer delays, lower power consumption, faster and more stable: supply decoupling and layout are less critical. There's also the TLC551 which can work down to 1V and is handy for single AA cell projects.Another beginner error is using large capacitors and resistors for the 555 timer, which leads to unpredictable delays and instability. The 555 is only really suitable for short delays under a couple of minutes or so, even the CMOS variants. The talk about hours on the data sheets is nonsense and pure marketing bull. For longer delays and lower frequencies, there are counter + oscillator ICs available, such as the CD4536, CD4541 and ICM7242: best monostables or the CD4060B and CD4521B: more suited to astables. They also have a wider power supply voltage and lower power consumption, than even most CMOS 555s. The only downside is they have a wimpy output, but it's easy to add a transistor to boost it.

author: Mechatrommer
author_rank: Super Contributor
timestamp: February 11, 2019, 11:48:22 am
content: Quote from: lieinking on February 10, 2019, 09:48:20 pmrefer to 555 datasheet to see what it does, and what other things around it do. you'll understand by going back (or down) further to simpler and simper thing... ymmv.

author: james_s
author_rank: Super Contributor
timestamp: February 11, 2019, 05:45:07 pm
content: You can go quite a long way into electronics without any heavy duty math. If you want to be a professional EE there is no getting around the math, but in my hobbies I rarely need anything beyond basic algebra. Learn Ohms law because you will use that all the time, but beyond that if it's just a hobby, focus on the practical side of things. As with programming there is a bit of a learning curve to get to where things start to get interesting.

author: dnwheeler
author_rank: Regular Contributor
timestamp: February 11, 2019, 10:37:26 pm
content: The books "Make: Electronics" and "Make: More Electronics" by Charles Platt progress nicely from very simple concepts and experiments to more advanced projects. There are also component kits available with all parts needed for the experiments and projects.

author: rstofer
author_rank: Super Contributor
timestamp: February 12, 2019, 09:28:35 pm
content: I ordered a copy of Forrest Mims; "Getting Started in Electronics" and it's a really good book. It covers all the usual topics like the nature of electricity, current flow, voltage and so on. I really wish it didn't describe current in terms of electron flow (pages 20 & 47) but that's just a preference. I understand why it was done but these days we have pretty well settled on 'current' flowing from + to -. Maybe it is confusing, maybe not...There is also a nod to analog computing on page 94 so that's pretty nice. It is the one topic regarding op amps that interests me.There are a lot of interesting circuits to build, something for everyone. For the beginner, it is much more approachable than "Learning the Art of Electronics" (in my opinion). I think I am pretty comfortable recommending the book for the absolute beginner. They will get from it in some proportion to how much time they spend reading the material and doing the experiments.https://www.amazon.com/gp/product/0945053282As to the experiments, what to do about parts? Each experiment is using something different, op amps, logic gates, resistors, transistors, capacitors, etc. What beginner is going to have this stuff laying around? Maybe the student should batch together a bunch of interesting projects and buy the components in a single order. And order some of the components, like resistors and capacitors, perhaps transistors, in multiples of 100.

author: darrellg
author_rank: Unknown
timestamp: February 12, 2019, 09:51:30 pm
content: Quote from: rstofer on February 12, 2019, 09:28:35 pmIt really depends on where you went to school. I was taught electron flow, because the flow of the absence of something is stupid. In reality, it works either way, as long as you are consistent. However, it is certainly NOT settled.

author: james_s
author_rank: Super Contributor
timestamp: February 12, 2019, 11:40:27 pm
content: I think it's useful to have a basic understanding that electrons actually flow from negative to positive but that conventional flow is used throughout most of EE and all the schematic symbols are drawn in this way. I don't think it's too confusing to remember that technically everything is backwards but from a practical standpoint we can pretend flow is from positive to negative and things will make sense.I had what I think was the same Mims book when I was a kid except the cover was green. It was quite good and I got a lot of use out of it. One thing I remember having difficulty with at the time though was figuring out the pinout of ICs. Seems like the book never actually showed the order of the pins which start at the lower left corner and count up going counter-clockwise around the IC. Maybe it's in the book and I just didn't see it, I was only about 10 years old at the time.

author: Wimberleytech
author_rank: Super Contributor
timestamp: February 13, 2019, 12:21:46 am
content: Quote from: darrellg on February 12, 2019, 09:51:30 pmIt is settled.