Having an alarm system is one of the best ways to deter burglars and keep your home safe. However, professional alarm systems can cost hundreds or even thousands of dollars. Luckily, with an Arduino microcontroller, some basic electronic components, and a little bit of coding, I was able to create my own DIY dog bark alarm that helps protect my home for less than $20.

In this guide, I will walk through the full process of making this alarm, from gathering materials to coding and setting up the device. With just beginner-level experience in Arduino and electronics, you can build your own economical version of this clever alarm.

Gathering the Electronic Components

The great thing about Arduino projects is that they don't require lots of expensive parts. Everything I needed for this build I was able to find online and in local electronics shops for very reasonable prices.

Here are the components you'll need:

So the total component cost was right around $15, which fits our budget nicely! Now let's look at the coding.

Coding the Alarm

One of the best things about Arduinos is how easy they are to program. We'll use the Arduino IDE to write and upload the code that will control our alarm.

The code has just a few key parts:

I've included the full code for the alarm below with comments explaining each part. No prior experience with the Arduino language is needed to use this code!

// Full Arduino code for the alarm

// Initialize speaker pin
int speakerPin = 8;

// Setup runs once when Arduino starts
void setup() {

// Init serial communication

// Set speaker pin as output
pinMode(speakerPin, OUTPUT);

// Main loop
void loop() {

// Randomly generate number 1-30
int randNumber = random(30);

// If 1, bark
if (randNumber == 1) {

// Wait half a second before looping


// Function to generate bark sound
void bark(int speakerPin) {

// Turn speaker on
digitalWrite(speakerPin, HIGH);

// Short delay

//Turn speaker off
digitalWrite(speakerPin, LOW);

// Longer delay before next bark


This code gives the illusion of a dog barking at random intervals to scare away intruders. The timing and duration of the barks can be adjusted easily by modifying the delay times.

Putting It All Together

Once the code is complete, it can be uploaded to the Arduino using the USB cable and Arduino IDE in just a few clicks.

Here are the remaining steps:

Circuit diagram for connecting components

And that's it! For just a small investment in parts and a little coding, you can build your own realistic Arduino dog bark alarm to help protect your home.


With crime on the rise in many areas, home security has become a priority for a lot of homeowners. But professional systems can be prohibitively expensive. The Arduino provides an affordable way to create your own DIY alarm that really works.

In this guide, I walked through how I built an alarm that randomly barks like a dog to scare away burglars. The total cost was less than $20, and it only took some basic coding skills to program the Arduino.

This could serve as either a standalone system or supplement to an existing home security setup. The barking sound it produces is realistic enough to convince potential intruders there is a large dog on the premises.

I hope this DIY Arduino project has inspired you to build your own devices for home security or other purposes. The Arduino platform makes it possible for anyone to inexpensively create their own electronics projects with just a little guidance. Let me know if you have any other questions!