If you've never created a circuit before then this is great project to get started. All you need to make a basic circuit is some common materials and components. A circuit is a closed path through which an electric current can flow. A circuit can be closed or open. If the circuit is closed all of the components are connected and the electrical current can flow. If the circuit is open then the connection is broken and the electrical current cannot flow. Circuits are used to send energy to turn things on like the motor in a drill or a bulb in a flashlight. A lot of things you use everyday contain circuits and circuit boards. A circuit board contains lots of little circuits that each have their own individual function. One circuit might turn on a motor while another circuit might make a buzzer beep. You can make a simple circuit out of just a light bulb, a power source, and some wires. To make this circuit you’ll need some cardboard, some paper clips, some paper fasteners, a battery, some tape, and a light. It’s also useful to have a pair of needlenose pliers and a utility knife. Circuits typically use wires and circuit traces to send electricity and signals along the circuit. In place of wires she uses paper clips and paper fasteners. If you're going to do the same thing, it’s important to make sure that these items are metal and don’t have any coating. They need to be conductive so that electricity flows through them wherever they touch. For this project, a battery is used as the power source. Batteries have a positive and a negative terminal. Some components only work in one direction so it’s important to note which orientation your battery is being hooked up. This battery supplies 1.5 volts of power. When choosing a light, you want to make sure you use one that is rated for low voltage. If the light is rated for 2 to 3 volts it should still work with one battery. First, Karen tapes down her battery. She adds a paper clip to either side to act as the wir
Simple circuits such as the ones Karen demonstrates are an easy way to learn about the difference between simple and parallel circuits. In a Series Circuit, all components are connected end-to-end to form a single path for electrons to flow. In a Parallel circuit, all components are connected across each other to form two sets of electrically common points. Another consideration you’ll need to understand when getting started with electronics projects is your choice between using stranded or solid wires. Both types of wiring are effective means of transmitting electricity, however, a stranded wire is more efficient in sending the electrons through your circuit. It’s also better suited for more intricate usages such electronic devices and circuit board where it offers the flexibility to be bent or twisted to connect electronic components. Solid wire is frequently used for outdoor or rugged applications where wire may be exposed to corrosive elements, adverse weather conditions, or frequent movement. It’s also a good choice for smaller projects where the flexibility of stranded wire makes it difficult to use. Karen uses solid wire to demonstrate the difference between series and parallel circuits because it’s stiff and stays attached better. In electronics, a node refers to any point on a circuit where two or more circuit elements meet. In a schematic, the node will be the wires between the components. In a circuit the current flows from high voltage to a lower voltage. The current flows through every path it can take to the point of lowest voltage (commonly referred to as ground). Two components are said to be in series if they share a common node and the same current flows through them. If the components share two common nodes then they are said to be in parallel.
To build your own Wigglebot, all you need is a battery and a motor. Karen pulls out some DC motors that she's taken out of some common objects. She's pulled a DC motor out of a cheap electric toothbrush that she found at the dollar store, some motors from video game controllers lying around the shop, a motor from a cell phone, and a computer fan. The computer fan won’t work as is, they’ll need to break some of the fan blades off so that it’s off balance. Vibrating motors work like DC motors, but a weight is placed on the end causing it to vibrate when it spins. Once you've found your motor, make sure that your battery has enough voltage to make it run. A lot of motors have an optimal rating, but a lot of times you can use a different voltage, such as a 9 volt battery to run a 12 volt fan. When you are connecting your motor to your battery pack, make sure your ends are long and stripped. Once your wires are twisted together be sure to cover it in electrical tape. This will keep it together and help prevent red wires from touching black wires. You don't want the red wires touching the black wires because that will cause a short and make it not work. You can then decorate your Wigglebot using stuff around the house such as pipe cleaners, pom-pom balls, popsicle sticks, paper clips, and googly eyes. You can even use electrical parts like old resistors, whatever you have lying around the house. For kids looking to do more, kick it up a notch by adding a capacitor. Both capacitors and batteries store electrical energy but work in completely different ways. Batteries have two terminals, chemical reaction inside the batteries produce electrons on one terminal and absorb electrons on the other terminal. Capacitors cannot produce electrons, they can only store them. Capacitors usually have two ratings, voltage and something called farads, a unit of measurement of capacitance. For this project, select a capacitor that is rated for approximately the voltage you'll be usin
Karen goes over wires and wire tools, and gives advice on selecting the right hand tools to get you started making circuits. Wire is the artery through which electricity flows. Wires come in two types, stranded and solid. If your application requires flexibility, such as in a robotic arm, stranded wire is ideal when the wire needs to be moved frequently. If little or no movement is required, such as when you are prototyping circuits on a breadboard, solid wire is easier to push through. Solid wire consists of a single strand or core of wire, insulated with non-conductive material. Its cheaper to manufacture and provides mechanical ruggedness, due to less surface area to be exposed to corrosives or environment. A stranded wire tends to be a better conductor than solid wire as the individual wires comprise a greater surface area. It’s good for connection between circuit boards where rigidity could cause stress due to movement. Electrical wire typically has an insulative cover that has to be removed to access the conductive metal inside. Conductors are materials characterized by their low opposition to electrical flow. Conductive means that electricity can flow through like with metals. Insulators are known for their capacity to stop the flow of current. Electrons flowing through a conductor or wire tend to generate heat. Thicker wires handle the heat better than thinner wires. Thinner wires can even burn up if too much electricity flows through them. Rubbers and plastics used as insulative materials. Karen goes over different examples of needle-nose pliers. For doing electronics work, small and narrow pliers work best. They allow you to get into tight spots in circuits and they make it easier to manipulate parts and wire. If using very small components, such as surface mount components, you may decide to use tweezers for a more precise grip. However, you may find that using needle nose pliers will give you a stronger, more secure grip on those same parts. The heavy-
Karen illustrates Ohm’s Law by making a simple circuit on a breadboard. To do this she uses two sources of power: a 2- AA battery pack that supplies 3 Volts and a 4 - AA battery pack that supplies 6 Volts to create a circuit that powers a red LED. Karen supplies 6 volts to the LED and demonstrates how it’s not a good voltage for it. If you want to use a 6 volt battery pack but don’t want to damage or burn out your LEDs you’ll need to add resistors to your circuit. In order to figure out how, you need to look at Ohm’s law. Ohm’s Law describes the relationship between voltage current and resistance. You use V for voltage (measured in VOLTS), I for current (measured in AMPS), and R for resistance, measured in OHMS). Current is measured in AMPS, named for a French mathematician Andre-Marie Ampere, the I originates from the French phrase for current intensity, intensite de courant. While current intensity has been shortened to just current, it is still represented by I for intensity. To make things easier to understand, Karen compares relationship between voltage, current, and resistance to water flowing through a pipe. Using this analogy, voltage is like water pressure, pushing the electricity through the circuit. Current is the amount of water flowing through the pipe. Resistance is the size of the pipe, which determines how much the flow is restricted. If the pressure (the voltage) stays the same and the resistance increases, making it more difficult for the water to flow, then the flow rate (or the current) must decrease. According to Ohm’s law, you need three variables: voltage, resistance, and current. To solve for resistance, you’ll need to find the voltage and current. The red LED is rated for 2.1 volts and 20 milliamps. In order to make the math a little easier, she rounds that to 2 volts. The battery pack supplies 6 volts, but they need to deprecate that to 2 volts and no more than 20 milliamps (equivalent to 0.02A) of current to power the red L
The main soldering tools you have as options are your soldering pencils and soldering stations. If you’re just getting started soldering or if you’re on a budget, you can start with a cheap handheld soldering iron. Ben cautions going to cheap on a soldering iron. They start at around 15 watts and go up to 80 watts which is bigger than you’d want to use for electronics. According to Ben, 20 to 40 watts is probably the sweet spot. Wattage refers to the current it draws, which lets you know how much power it has in order to melt solder. The higher the wattage, the more solder it can melt or the faster it will melt it. One thing you need to check for is that the plug for your soldering iron has a ground pin. If a device has exposed metal then it’s good for it to have a grounded plug because that allows static to discharge into the earth instead of building up on your tool. Reasons you’d want to get a soldering pencil is that they are cheaper, they are easier to store, and they come with a stand which you want to be sure to use. You don’t want to set a soldering pencil on the table. Some of the drawbacks include the fact that they don’t have a variable temperature control. Ben and Karen take a look at three different models of soldering stations. If you’re using a soldering station, you always have a place to store your soldering iron, and many of them come with a place to put a sponge or a brass pad. Each station has some sort of temperature control, how fine that is will depend on the model. The 21-7945 Tenma Soldering Station uses knob control that goes from yellow up to red, so you don’t get the exact temperature. The 21-10115 Tenma Soldering Station has a digital display. Karen likes it because it gives you three preset temperatures but also allows you to fine-tuning of the temperature. Ben notices that it has a transformer in it. This is good because a transformer allows you to have higher current faster, allowing it to heat up quickly. If a solde
We use electricity everyday in our homes. Devices plugged into the wall are powered by AC electricity. Handheld devices like our smart phones are powered by DC electricity. Electricity for our devices comes from outlets in our walls and from batteries but how does that work? How does electricity get from one point to another? To explain how electricity works, Karen starts with the most basic parts. Everything, all matter, is made up of atoms. Atoms are made up of particles consisting of protons and neutrons in the core, surrounded by electrons. In an atom, protons are positively charged, while electronics are equally negatively charged. Atoms normally contain the same number of protons and electrons. If this is the case, these atoms are electrically neutral, having no charge. However, this can be changed. An atom can gain or lose an electron by passing it to or from another atom. This causes an atom to become an ion, meaning it has extra or is missing electrons. If an ion has extra electrons it is negatively charged, while an ion with missing electrons is positively charged. Charged ions exert force on each other.
Karen is using acrylic that is 0.1 inches thick. You could also use 1/8 inch or a similar thickness. You don’t want to go to thin, because then it might break. You don’t want to go too thick because it’ll be difficult to deal with. When deciding the size of your acrylic, you want to stick around two to three inches in either rectangular or square. If you go too big, the light of your LED won’t reach your design, and it won’t light up very well. For this particular application, if you’re only using one LED, then you want a smaller design. When drawing your design, you want to make sure that your lines are not going to be too thin because there will not be enough mass to catch the light significantly to really show off your design. When you make your design you want to make sure that you’re using nice, bold lines. Karen draws extra lines within the border of the acrylic. This is because when it’s done, she’s going to be putting aluminum tape around the edges, and this is to make sure that the design isn’t covered up later. When her design is done, she tapes the acrylic down so that it doesn’t shift, and so she can get good alignment between the acrylic and her design. Next, you’re going to want to etch your design. You can use an exacto blade or any kind of hobby knife that has a sharp pointy end. She suggests using electric etchers if you have a child doing this. For her example, she etched in a few different techniques so she could show you the differences of direction of scratch and how it affects your design when you place your LED. She goes over some of her different etching techniques. She suggests doing cross hatching, if you don’t have a specific design in mind. Scratch in opposing directions so that no matter where you place the light, it’ll still catch it. She recommends, though it’s not required, cutting a little notch in the edge of your acrylic to hold your LED in place and to keep the light pointing exactly where you want. S
This is a great, DIY Beginner electronics project good for elementary school levels and up. I’ve even had Pre-K children use these, but most of them still needed a little help. For our circuit blocks, we’re going to include three main types of components: power sources, loads, and interrupts. The power sources we’ll use will be batteries, which provide DC power or direct current power, meaning a current that flows in one direction. I recommend 2AA 3V battery packs, and maybe a 4AA 6V battery pack. You could even use a 9V battery and clip if you’d like. You’ll need to be careful with more than 3V, but I’ll explain why later. The load in a circuit is anything that consumes power. We’ll be using LEDs, motors, buzzers, and fans. You can also use incandescent lights from either strand holiday lights or buying sockets that hold bulbs. Ideally you’ll want components that are rated for around 3V and for DC power. For motors and fans, they may be rated for more power, but try to get as low as you can near 3V. These motors and fans can handle more power, but will still work at 3V. Most LEDs are rated for 1.5-3V DC. Be careful with the LEDs. If they are fed too many volts, they’ll burn out and stop working. While that’s true for most components, LEDs tend to be less tolerant to voltages above their rating. We’ll also make blocks with interrupts, like buttons, switches, and potentiometers.
For this project you’ll need an Arduino Uno the USB cable to plug into your computer, breadboard, jumpers, a tact switch, two red and one LEDs, three 220 ohm resistors for the LEDs, and one 10 kiloohm resistor. The code you’ll need to do this project is included in the Arduino Starter Kit book. The Arduino Starter Kit book includes circuit diagrams and code which is referred to as sketches. A sketch includes a set of functions followed by curly brackets, such as void setup () and void loop (). Anything you put in the curly brackets is the code that is executed when the function is called. Sometimes you will need to create what are known as variables for your code. A variable are items that you want your code to remember so that you can reference them later. One good thing about variables is that if you use the same variable throughout your code and need to adjust the value of the variable, you only need to set the variable to another value at the top of the code. Karen shows you how to set an integer as a variable for the project. After defining the variable, Karen moves along to the setup code. The setup is where we configure the pins so that the Arduino knows what’s an input, what’s an output, and which pins we’re using. In her code the 3 LED are designated as outputs, for pinMode, and the button is designated as an input for pinMode.