We now learn about buzzers and use them to build a simple game.
There are different types of buzzers so we will not be getting into the details of their construction but in short, a buzzer produces sound when voltage is applied to it.
This is the symbol for a buzzer and applying 3V to the buzzer contained in BBox 1 will produce a sound. The sticker is meant to protect the buzzer from damage during automated assembly but you don’t have to remove it as they are generally loud either way.
Here’s what the circuit looks like and you can see that the buzzer is simply placed between the positive terminal and transistor. When the transistor is switched ON, the negative terminal of the buzzer will be connected to the ground, generating a sound.
The rest of the circuit is very simple. We have two probe points and when they come in contact with each other, the transistor switches ON, which then switches ON the LED and buzzer. Technically, you could simply use a switch to control a buzzer but we used a transistor here as we would like to turn this into a game and it’s always better to prevent exposing battery terminals directly from a safety point of view.
Let’s use the breadboard layout to build and test the circuit.
You can use this circuit to form a simple game by using two pieces of conductive metal wire.
One forms a loop while the other forms a unique shape or pattern, like this. They are both connected to the individual probe points and the buzzer sounds when they come in contact.
The goal is to navigate the pattern without touching the two wires. You can vary the diameter of the loop and change the pattern to increase the difficulty.
Now that you’ve learnt about buzzers, you can add them to the previous alarm circuits to generate a sound when they are triggered.
We will learn about logic gates in the next post.