Have you just bought a starter kit, or are you hesitant to buy one because you’re not quite sure what’s in it? You’re not alone. Faced with a box full of electronic components, it’s easy to be overwhelmed. Here’s a guide to exactly what you’ll find in your kit.
We’re using the SunFounder UNO Starter Kit, available for $49.99, which we recommend because of its fantastic value for money. If you have a different starter kit, it’s likely you’ll find some (but not all) of the same components, so it’s still useful to read. You may also want to check our electronics skills for beginners article.
What’s Included in an Arduino Starter Kit?
The most important piece of the kit is the Arduino itself. The Uno is one of the more basic models, but for a beginner it’s completely serviceable and there isn’t much you can’t do with it. If you’re looking for bigger or more powerful models, the Arduino Mega fits the bill; while for projects that require use of very small spaces the Mini or the Pro Micro should be more than adequate.
The model in the Sunfounder kit is actually an unofficial Uno clone. Since the Arduino design is open source, it’s perfectly legal for other companies to reproduce or modify as long as they don’t brand it as an official “Arduino” board.
The breadboard is a tool used to experiment with circuits without the need for soldering wires. In essence, it’s a temporary testing tool with which you can make and break electrical connections quickly. The breadboard consists of a sheet of plastic with holes on the top, and metal rails connected underneath: components and jumper wires are inserted into these holes. Each of those rows of 5 holes in the middle is connected. On the outside, the entire column is connected: these are typically used as common power lines.
The Sunfounder kit comes with several LEDs in various colors (red, yellow, green and white) as well as a single RGB LED. The RGB LED features 4 pins (one for each color and one common cathode – or ground), so you can experiment with color mixing, or create displays of random color. It’s quite cool to play with once you dive into code. In fact, for a beginner, it was very satisfying to see instant results when I edited my first bits of Arduino code.
One important thing to note is the pins on the LED. Typically the positive is longer than the negative, but if yours are the same size, then look for a flat side on the base of the actual LED. The leg on the flat side is the ground or negative.
The USB cable connects to your Arduino, as well as your PC or a separate power supply. In addition to providing power to the unit, the cable transmits data – in the form of programs or sketches – from the PC to the Arduino. Once uploaded, the Arduino stores the information even if it’s disconnected from power. To erase the program, you simply upload a new one.
While the Arduino will store your program indefinitely, even without power, it’s important to note that the board itself has no power source, thus it will not work unless it’s connected to a power source of some kind. As well as power from a USB port or wall charger, a 9 or 12v DC input can used.
40x Pin Header
This is a series of 40 pins that can be broken or cut to fit any size. Components often come with pins, but if you’ve bought something that only has holes, a pin header can be soldered in to make it easier to work with on a breadboard.
Ceramic Capacitor (10nF & 100nF)
Capacitors store and discharge energy: they’re generally used to regulate voltage or smooth out a signal. A specific example of this is “debouncing” a button press. While pressing a button may seem like a simple, quick action to you, but on an electrical level it can in fact generate a series of very quick high and low electrical noise. Debouncing is process of smoothing this so that a single button press is just that.
H Bridge (L239D)
The H-Bridge is an integrated circuit that allows voltage to be applied in either direction. These are typically used in conjunction with the DC motor to allow it to spin both forward and backward. L239D is actually a dual H Bridge, so you can drive 2 motors, useful when building simple robots.
Accelerometers are made to measure acceleration and tilt in one to three linear axes (x, y, z). While it does a lot of things, it’s commonly used to measure distance, side-to-side movement, and sudden stops and starts by all types of devices. For example, if you have a device that only moves in one direction, such as a line following robot, then the accelerometer allows you to get a reading for distance traveled by factoring in acceleration and time to measure the distance travelled by an item.
The DC motor is a component containing a metal rod that spins when connected to power. The spinning rod can then do simple things like spinning a fan, or running a pulley system that creates motion (in an RC car, for example).
The optocoupler allows you to transmit a signal between two parts of a circuit while keeping them electrically isolated. Internally, it’s just an LED with a photoresistor. Conceptually they’re quite similar to a relay, but differ in a number of ways:
- They’re smaller and lighter than a relay.
- It’s solid state, meaning there are no moving parts and thus offers fewer opportunities for failure.
- It requires less current to activate than a relay; but conversely, can only switch small amounts of current.
Resistors (220, 1k, 10k, 1M, 5.1m Ohm)
Resistors are components that limit the flow of current to other components. When you plug a wire into the 5v power pin on an Arduino, but a component can only handle 3.5v, you need to find a way to restrict the amount of power (current) it receives in order to avoid damage.
James wrote a piece that covers basic components in a starter kit, and his pipe analogy is right on the mark.
“If you like to think of a circuit as a network of water pipes flowing in one direction, a resistor would be like connecting a smaller pipe to the end of a larger one. The main reason for doing this is to protect other components from damage.”
The resistors in our kit come in various values (220, 1k, 10k, 1m, 5.1m Ohm). This was confusing to me at first, as I couldn’t decipher the value of each capacitor. The important thing to remember is the colored bands hold all of the information you need in determining the value of each capacitor. The first two represent a number value, while the next determines the number of zeroes you’ll add to the end of it. The fourth colored band is known as a tolerance band, and it shows the variance of the resistor, which is something you probably don’t need to worry about at this point. This chart proved very handy.
You can work out what value of resistor for a particular LED using this handy tool – but you’ll need to know the LED’s working voltage and current.
I won’t spend too much time on a switch as most of us already know the basics of what they do. Essentially, it cuts off or allows the passage of current which effectively acts as an on/off lever for your projects.
However, it is worth understanding the different types of slide switch, such as SPDT (which is what’s included in the kit) and DPDT. The first two letters – SP and DP – mean “single pole” and “double pole”, which is the number of things they can switch a once. A single pole switch (as in the photo) has a single set of contacts, so it can switch one thing on or off. A double pole switch has two separate sets of contacts which are simultaneously operated by the same switching action.
The second set of letters – ST or DT – means “single throw” or “double throw”. Single throw switches are those which are just open or closed. Double throw (such as in the kit) has a single common pin, and switches between making contact with the two other pins. A double throw switch can be used to simply turn something on or off, but can also p
The 7-segment display is an integrated package of LEDs which act as a digital readout for projects that need a display of numbers. While it can’t handle images or the like, the display is actually quite perfect for things such as electric dice, an alarm clock, or even a countdown timer (if you have several of them).
The rotary encoder is a rotational measuring device that is used for counting rotations or to create wheel controls – like knobs – that can turn infinitely. They’re a little more complex to wire up than a potentiometer, and they output the number of “steps” of rotation that have occurred.
To give you an idea how it’s used, my first project with the rotary encoder involved turning it in order to brighten or dim the RGB LED.
Though visually similar to a rotary encoder, a potentiometer has a fixed range of motion and produces an easy to read analog output to show exactly where it’s been rotated to. The main difference is that it has a fixed start and end point.
A shift register is a kind of short term memory chip that receives data in series, then “shifts” it all out once. In practical terms, this means you can free up I/O pins on the Arduino. Crucially, shift registers can also be daisy chained together, allowing you to drive many more outputs than would otherwise be possible.
They’re a bit harder to program, but when you’re ready to have a go you can follow our shift register beginner project.
The LCD display features a 16×2 character display that can show static or scrolling messages. Typically you’d use this to output sensor readings. Be warned, the displays uses a lot of output pins, so you won’t have many left to play with.
Dot Matrix Display
The dot matrix display features an 8×8 grid of LED lights within a plastic housing. Each of these LEDs can be programmed to display together, or independently to create simple messages or images. Bigger and smaller dot matrix displays are also available.
Transistors (PNP and NPN)
Transistors are the foundation of modern electronics. Both PNP (positive, negative, positive) and NPN (negative, positive, negative) transistors are controlled by electrical current and act as a digital switch – used in digital logic and signal amplifying circuits. Each type of transistor has a base, collector and emitter.
While the two are nearly identical, the difference is in both having completely opposite polarities. The PNP flows out, from the emitter to the connector. The NPN flows in, from the collector to the emitter. If you need a simple mnemonic, remember this:
NPN: Not Pointing iN
The push button is a simple button that makes or breaks an electrical contact when pressed. You can program this kind of interruption to the circuit to any number of different effects depending on the project, but might include things like: rolling dice (for display on the LCD or dot matrix), sounding the Piezo buzzer, or starting/stopping an LED light show.
You may also come across the terms NO or NC when working with switches and relays: they mean “normally open” (a connection is not normally made, and it be activated to make the connection), and “normally closed” (the connection is normally made so that current flows – the switch must be pressed to break the connection).
A diode lets electrical current flow in only one direction. Typically this is used to protect components or circuits from reverse current surge, such as from a motor that continues to turn after the power has been switched off.
Male to Male Jumpers
The jumper wires are for making connections on the breadboard, as well as from the breadboard to the Arduino itself. The starter kit includes several colors and although the color doesn’t matter, it’s a great way to organize your projects.
A common beginner question is how to do a project if you have jumpers that don’t match the colors of the diagram you’re using to build it. Colors are merely for organization purposes and they really don’t matter. You may however want to adopt the rule of using red for +ve power, and black for ground, since that’s a universal standard (but again, it doesn’t affect functionality).
The Piezo buzzer is merely a simple speaker that can beep in different tones. The speaker itself emits a solid tone once it’s connected to power, but you can program them within the code to change the length and frequency of the sounds emitted. James used it to create a simple Arduino alarm system.
So, if you’re a confused novice like I was, this should give you an idea for what the components in your kit are, and how we’d use them. Over the coming weeks, we’ll dive a bit further in-depth each week until we get a chance to tackle some projects using these components.
What did I miss? Is there a piece in your kit you can’t identify? Shoot us a description or a link below in the comments. In addition, are there any Arduino-related beginner problems you’re running into? Let us know and we might do a write up in a future piece.