Hello again. In this Instructable we will cover a very broad topic: everything. I know that may seem impossible, but if you think about it, our entire world is controlled by electronic circuitry, from water management to the production of coffee to commuting to work/ school. And all of these electronic devices are controlled by very similar components (resistors, transistors,potentiometers, capacitors, switches, and many, many, more). These components all perform one of the following tasks- taking in data, processing data, and outputting data. For example, a mouse (which is a combination of lots of small pieces) measures position, a computer processor thinks about that information, and the computer monitor moves the cursor according to your mouse. Let's start this Instructable by going over some of the aforementioned components.
Step 1: Switch
Ahh, the good old switch. There is one of these in almost every electronic circuit ever made. If you have a good circuit that doesn't have one, please comment below (coin cell batteries + LEDs don't count here). Anyway, the switch has one job- to let electricity through, or not. There is not much left to say about this unspoken hero of electronics.
Step 2: Resistors
Resistors are a cornerstone of any circuit. I would be hard-pressed to find any PCB (that's Printed Circuit Board, for the layperson) that doesn't have one of these vital voltage- reducing objects. Resistors are used to take one voltage and reduce it to a lower one. Not much else needs to be said about these vital little components.
Step 3: Trasnistors
Transistors can be confusing, especially with all the different kinds. Essentially, a transistor is a semiconducting switch triggered by an electrical current. These tiny, but powerful switches come in various different models, each with slightly different purposes. Every modern circuit capable of processing data has one of these guys.
Step 4: Capicitor
Capacitors are a means for storing small amounts of electricity. This is how they work: There are two pieces of metal partitioned by a non- conductive material. The type of non- conductive material, or dielectric, determines the kind of capacitor, and what it will be used for.
Step 5: Potentiometers/Rheostats
The Potentiometer is a fascinating, and important, type of variable resistor. There are 3 pins- 2 inputs and one output. Using all three pins makes it more of a sensor for inputting data, whereas using two pins make it a plain old way of choking voltage. If you are anything like me, you wanna know how it works. Basically, there is resistor that a slide or wiper moves along, making the distance the electricity fluctuate depending on the position on the wiper/ slide. This increases, or decreases, the resistance. Potentiometers generally look like the picture above, but their shape and size may vary.
Step 6: Brushless DC Motor
This thing is pretty cool. I used to show small children (they were technically my age- I was in fifth grade) the DC motor by connecting the terminals to a 9V battery and voila- it spun! All the other kids were jealous (or so I fantasized). You can wield the power of the motor as well. It is a very simple device- there are two or more electromagnetic coils that alternate polarity. Then there is a normal magnet that spins because of the repulsion from the electromagnets (see pic above).
Step 7: Relay
A relay is a switch activated by an electric current. I diagrammed it on my whiteboard in the pic above. Essentially, An electromagnetic coil repels a magnetic electrode, making it touch another electrode, thus letting current through the circuit.
Step 8: Piezo Buzzer
The Piezo Buzzer is one of the most annoying things in the universe. I mean, who wants to hear "BEEP, BEEP, BEEP!" whenever we're cleaning out the fridge? Or when the microwave is going off, but you don't want to stop watching Sherlock, and you are forced to endure "Beep beep, Beep Beep, Beep beep." However, these tiny sudo- speakers are an important part of electronic design. If you want your circuit to give audio feedback, but don't need a regular speaker, these are your go- to components. They make noise with a little metal plate called a piezo. Electricity runs through the piezo, causing it to vibrate very fast. This motion makes squiggly air, otherwise known as sound. The pitch of the squiggly air is determined by the speed of the vibration, and the speed of the vibration is determined by the voltage.
Step 9: LED Bulbs
These little lightbulbs are so common in electronics it is uncommon to not have at least 20 of these in your house. They are small, affordable, energy efficient, super- bright, and they do not get hot. What's not to like? Basically, the light in an LED, or Light Emitting Diode, is created by electron movement in the semiconducting material that is roughly the equivalent of filament in an incandescent light bulb. Even in the most boring circuits, I enjoy placing little green or white LEDs to liven things up.
*Warning: Always choke the current going into an LED with some kind of resistor. They usually operate at a low voltage, around 3.3 volts.
Step 10: Microcontrollers
This step is different from the others, as it is about not a component, but a topic. Microcontrollers are simple computers that are used to absorb, interpret, display, and respond to data. Most microcontrollers use all or most of the components we discussed. Since there are so many kinds of microcontrollers, I will give you three of the most highly recommended ones for beginners- Arduino, Raspberry Pi, and BeagleBone. These three boards are all programmable and can be used for any number of projects.
*Disclaimer: I only own the Arduino and Raspberry Pi, so I can't vouch for the BeagleBone.
Step 11: Programming
Step 12: That's All, Folks
This concludes the Instructable. Thank you for reading, and please take the time to vote for me in the Beginner Electronics contest if you enjoyed this guide. I sincerely hope you feel inspired to take up electronic design now.