18 Replies Latest reply on Nov 21, 2017 9:02 PM by dougw

    Getting Started on a Breadboard

    theheckwithkaren

      I run workshops to teach STEM basics, sometimes to adults, often to children. Soldering is not always an option, so I've been trying to come up with simple projects to build on a breadboard with fairly inexpensive parts, to show how to make a circuit that does something visually obvious, such as turn on a motor or lights. The groups that organize these workshops frequently have very low budgets to where they couldn't afford enough Arduino or Raspberry Pis or the like for the entire group. I'm frequently given a $50-100 budget for anywhere between 6 and 30 individuals. What fun projects could be built on breadboards that are simple enough for a child to be able to understand? I've found that the best received projects are ones with a result that is the kids can see; a light turns on, a motor spins, etc.

      One of the goals of these projects would be reusing the parts for other projects or with another group, so nothing with the project should be destructive.

      What simple circuits helped you to learn electronics?

        • Re: Getting Started on a Breadboard
          fmilburn

          Hi Karen,

           

          There are lots of simple circuits to blink, buzz, move and even sense on a breadboard as you point out. I think the key with kids is to get results quickly, at least at first, and tie it to something they understand and interests them. In the past I have started with a LED and battery, then progreesed to motors and buzzers.  Inexpensive transistors can be used as switches for all sorts of circuits - say with an IR beam that buzzes when interrupted (burglar alarm).  All without a microcontroller. 

           

          But microcontrollers can be done inexpensively on a breadboard also.  I use a MSP430 in most of my projects and it is easily breadboarded and a single Launchpad can be used to program multiple microcontrollers.  The same with an Atmel/Arduino.  It is surprising how needs to be added to a modern microcontroller to get it working.  See for example:  Use Your Launchpad as a Programmer | Four-Three-Oh!

           

          I have enjoyed putting together theres type of classes and know how much effort it can take. Good luck and thanks for what you do to educate!

            • Re: Getting Started on a Breadboard
              theheckwithkaren

              I agree, that kids really need results quickly. At least at first. And keeping projects relevant is always key to keeping them interested. All very good points. Hmmm. I'll have to look into using an MSP430. Thanks for the input!

                • Re: Getting Started on a Breadboard
                  beacon_dave

                  Some children need 'real world context' applied to their education and yet schools often appear to totally overlook this aspect. Also you often need an element of progression rather than just repetition to keep the interest going.

                   

                  Pico Technology have a list of educational experiments (mainly centred around data acquisition) which may give some ideas of how to interact with the real world:

                  https://www.picotech.com/library/experiments 

                   

                  Looking at the school curriculum and trying to spot areas where real world context could be applied via the maker type scene would probably be beneficial as well. The sciences should be a good bet, however I suspect that maths needs it more than anything.

                   

                  As already has been mentioned, visual and audible stimulus can help maintain interest at the start however there is a limit to the wonder of a flashing LED. Sooner or later you are perhaps going to need to turn that flashing LED into a DIY 7-segment display that can count from 0 - 9 at which point you can progress to ready- made 7- segment displays at which point you can progress to counters at which point you can start counting real world events, and then timers to time real world events...

                  1 of 1 people found this helpful
                • Re: Getting Started on a Breadboard
                  fmilburn

                  I found these elsewhere on E14 where they were posted by shabaz and thought them worth repeating here:

                  1 - 200 Transistor Circuits

                  and

                  101 - 200 Transistor Circuits

                  and

                  50 - 555 Circuits

                  and

                  100 IC Circuits

                   

                  Regarding the MSP430, if used for beginners then have a look at Energia which is a fork of Arduino:  Energia

                  2 of 2 people found this helpful
                • Re: Getting Started on a Breadboard
                  DAB

                  Hi Karen,

                   

                  I would start with the venerable 555 timer chip.

                  It would let you explore both analog and digital circuits so you can start with simple logic, clocks, PWM, and then look at analog issues like variable triggers, and wave shaping.

                   

                  DAB

                  4 of 4 people found this helpful
                  • Re: Getting Started on a Breadboard
                    gam3t3ch

                    For me starting with a 555 timer helped me the most back in the day I enjoyed making projects and trying new things with the 555 timer, this brought me into other projects with IR as well for projects also making a aruidno on a breadboard is fun as well. only thing that isn't cheap is a FT232RL break out board but I am sure  a alternative could be in place I suggest the 555 and the ATmega328 because both can be used from beginner to advanced and help with the ability to prototype a lot quicker and being able to implement them into future projects.

                     

                    I say these two would be great choices as its accessible to everyone and lots of information for research and ideas.

                     

                    These are my two favorites to play with and tinker with ever now I find uses for both in projects. 

                    2 of 2 people found this helpful
                    • Re: Getting Started on a Breadboard
                      jw0752

                      Hi Karen,

                      If a budget was an issue I would look at some of the cheap kits that are available from Chinese sources. For example:

                       

                      https://www.banggood.com/5Pcs-NE555-CD4017-LED-Flash-DIY-Kit-3-5V-Light-LED-Module-p-1020006.html?rmmds=search&cur_warehouse=CN

                       

                      Here are 5 Kits for $5.00.  I would start by prepping the kits so that you could bread board them and talk about the components and the circuit as you go. After the circuit is understood and bread boarded the students will have the option to move the parts to the circuit board and make a more permanent trophy for their class as well as learning some valuable soldering skills.

                       

                      John

                      2 of 2 people found this helpful
                      • Re: Getting Started on a Breadboard
                        jc2048

                        Here's a simple circuit for producing a sound from a piezo disc. Normally, beginners get introduced to the astable multivibrator as their first oscillator (I think that was the first true electronic circuit I ever built), but I've gone in a different direction here. This is a current-mode astable. I've simplified it a bit - resistors rather than current sources, and the bias arrangement holding the base of the first transistor is a bit useless but seems to work anyway [on the evidence of this, don't give me a job as an engineer anyone].

                         

                        Here is the circuit

                         

                         

                        Here it is on a breadboard - the red and black leads go to a power supply set to 9V. The current consumption is a few milliamps, so it would be fine on a small 9V battery.

                         

                         

                        And here is a waveform, because waveforms always look cool when you're blogging about electronics (this is the voltage across the piezo disc). With the 100n capacitor, the frequency is just over 2kHz.

                         

                         

                        As it stands it's a bit boring - just a single, monotonous (literally, a mono tone) sound - but it could be extended to do other things. With a latch it could be an alarm. With a selection of different resistor values it could be an electronic organ (try experimenting with different value resistors from the emitter of the lefthand transistor to ground - from 1k to 10k gives about an octave range in sound). Anyway, just an idea - it's certainly cheap and all the bits can be reused in other circuits.

                        1 of 1 people found this helpful
                          • Re: Getting Started on a Breadboard
                            jadew

                            Was going to suggest that. My first circuit was an astable multivibrator and I had lots of fun with it. Particularly, I was using it to mess up the TV reception when my grandparents were watching the news and I couldn't follow my favorite cartoons. Fun times.

                             

                            I'd also suggest a couple of off the shelf voltage regulators to show how you can get different voltages and also explain power and power dissipation.

                            • Re: Getting Started on a Breadboard
                              jc2048

                              I was being a bit optimistic when I suggested that the circuit above could be used as an electronic organ. I've just tried it with a potentiometer to vary the value of the emitter resistor of the leftmost transistor and, instead of the tone varying smoothly, it jumped in steps - the circuit was evidently being pulled to the different physical resonances of the piezo disc. It's interesting to play with - I've just spent a while getting all manner of weird sounds out of it - but for a beginner the astable multivibrator or a 555 timer would probably be a safer bet.

                               

                              Other problems, if anyone feels inclined to experiment with it, are that the right transistor will sometimes oscillate at a few megahertz (superimposed on the wanted  waveform; emitter followers are prone to that kind of thing; adding a small-value resistor to the base will stop it) and it doesn't always start up, depending on the components used and the frequency you're trying to achieve.

                              1 of 1 people found this helpful
                            • Re: Getting Started on a Breadboard
                              e14phil

                              I highly recommend a few SUPER simple, Super quick exercises just to to stress how the electrons flow and the how the power rails work.

                               

                              1) Draw a circular circuit of  Battery > Resistor > LED.

                              2) Show them what direction the sockets are connected

                              3) Show them the Power Rails

                              4) Wire the Battery > Resistor > LED on the breadboard, stressing the flow of the circuit.

                              5) Add the complexity of a push button / switch to the diagram and then to the circuit

                               

                              I know its super over kill simple, but it took seeing it in that order for me to put aside my apprehension/prejudices about breadboards being "complex and scary" when I first started.

                               

                              Phil

                              2 of 2 people found this helpful
                                • Re: Getting Started on a Breadboard
                                  theheckwithkaren

                                  That's a really good point. Learning electronics has been a constant struggle for me. Learning to read a diagram and knowing how to make that translate into parts on a breadboard really connects the dots. As someone that tends to learn quickly, I've tried starting with more complex circuits and projects and struggled to really understand how they work. I could make them work, but didn't understand what was happening within the circuit. Sometimes starting at the very basics is what is needed to create a solid foundation for more advanced learning later. Thanks!

                                    • Re: Getting Started on a Breadboard
                                      DAB

                                      Back in Tech School (1970), they started with Ohms law and had us play with resistors and DC voltages.

                                      Then we moved on to capacitors, inductors and AC voltage.

                                      We then worked up to using tubes to build circuits.

                                       

                                      At every step, we worked with simple circuit designs to get everyone familiar with circuit layout and how to trace the circuit from input to output.

                                       

                                      It takes a while to make this process intuitive.  Persistence is required.

                                       

                                      Keep at it until it becomes second nature.

                                       

                                      DAB

                                      • Re: Getting Started on a Breadboard
                                        luislabmo

                                        I think e14phil's list is on spot, I could add few more which can come after his list and are very easy on the budget.

                                        • Explain how a switch works (battery + resistor + led + switch), here you can explain with push buttons Normally Open/Close and maybe add examples with a slide switch.
                                        • Ohm's law: using different resistor's values changes the led brightness (battery + various resistors + led)
                                        • Dimmer (variable resistors): (battery + potentiometer + led + switch). Here they can learn how a Potentiometer works.
                                        • Demonstrate how capacitors work -Charge/Discharge- (battery + electrolytic capacitor + resistor + led)

                                         

                                        Moving to some more complex, transistors / 555 can be added to the mix and they all re-use previous concepts learned (capacitors, ohm's law, switches, variable resistors)

                                        • Blinking led's
                                        • Dimmer
                                        • Police siren

                                        I know micro-controllers can be too advanced, but if you ever get there, all examples above can be done easily with very few lines of code using an arduino or ATtiny micro-controller. Very good example here.

                                         

                                        Luis

                                        3 of 3 people found this helpful
                                    • Re: Getting Started on a Breadboard
                                      beacon_dave

                                      theheckwithkaren - what other resources if any do you have access to in addition to your budget ?

                                       

                                      Could you manage to use online services like Tinkercad Circuits (formally circuits.io) to make the budget go a bit further ? With the likes of Tinkercad you get free scopes, meters, signal generators, etc. which allow the student to explore electronics in an interactive manner. Sure there are limitations to simulation but it is a low cost way to get through some of the basics.

                                       

                                      If 'teacher' has access to an ICSP programming device, then you could perhaps buy a bag of cheap AVR microcontrollers and program them up to perform different functions that can then be dropped into the breadboard to turn the Tinkercad simulations into physical projects but without the full expense of an Arduino development board.

                                       

                                      Students will feel like they have achieved something very quickly and then once 'hooked', you can start to bring in more of the theory.

                                      • Re: Getting Started on a Breadboard
                                        dougw

                                        Static electricity is always good to get kids and adults thinking......

                                        https://www.youtube.com/watch?v=ViZNgU-Yt-Y

                                         

                                        and  other experiments can be cool too:

                                        https://www.youtube.com/watch?v=c7ljY6285CE