Remote Controlled Bulb

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On October 12, 2025

Have you ever imagined switching your light ON and OFF with your TV remote?
In this project, we’ll turn that idea into reality by building a remote-controlled bulb using an Arduino, an infrared (IR) receiver, and a relay module.

It’s a simple and fun home automation project that teaches how to read IR signals, decode remote buttons, and control electrical devices safely.

What You’ll Need

Component	Quantity	Description
Arduino Uno / Nano	1	The brain of the project
IR Receiver (e.g. TSOP1838)	1	Detects infrared signals from a remote
Relay Module	1	Acts as an electronic switch
IR Remote Control	1	Any TV or set-top remote works
Jumper Wires	—	For connections
Bulb or LED Lamp	1	The load controlled by the relay

Circuit Connections

Arduino Pin	Connected To	Description
D3	IR Receiver OUT	Signal pin
5V	IR Receiver VCC	Power
GND	IR Receiver GND	Ground
D2	Relay IN	Relay control pin
5V	Relay VCC	Power
GND	Relay GND	Common ground
Bulb	Through Relay Output	Switched load

🔸 Important: If you’re working with mains electricity (110V/220V), test with a low-voltage LED bulb first for safety.

🧮 Step 1: Get Your Remote Button Code

Before controlling the bulb, we need to find out what IR code your remote sends when you press a button.

Upload this simple sketch to your Arduino:

#include <IRremote.hpp>

#define IR_RECEIVE_PIN 3  // IR sensor pin

void setup() {
  Serial.begin(115200);
  IrReceiver.begin(IR_RECEIVE_PIN, ENABLE_LED_FEEDBACK);
  Serial.println("Press any button on your remote...");
}

void loop() {
  if (IrReceiver.decode()) {
    Serial.print("Code received: 0x");
    Serial.println(IrReceiver.decodedIRData.decodedRawData, HEX);
    IrReceiver.resume();
  }
}

🧾 What to Do:

Open the Serial Monitor (set baud rate to 115200).
Press any button on your remote.
You’ll see something like this:

Code received: 0x649BF708

Copy the hexadecimal value (the part after 0x).
That’s your unique remote button code.

We’ll use that code in the next step.

💡 Step 2: Use the Code to Control the Bulb

Now that you have your remote’s button code, let’s use it to control a relay connected to a bulb.

Replace 0x649BF708 in the code below with your own remote code.

#include <IRremote.hpp>

#define IR_RECEIVE_PIN 3  // IR sensor pin
#define RELAY_PIN 2       // Relay control pin

bool bulbState = false;   // Bulb initially OFF

void setup() {
  Serial.begin(115200);
  pinMode(RELAY_PIN, OUTPUT);
  digitalWrite(RELAY_PIN, LOW); // Start with bulb OFF

  IrReceiver.begin(IR_RECEIVE_PIN, ENABLE_LED_FEEDBACK);
  Serial.println("Ready to control bulb with remote...");
}

void loop() {
  if (IrReceiver.decode()) {
    unsigned long code = IrReceiver.decodedIRData.decodedRawData;
    Serial.print("Code received: 0x");
    Serial.println(code, HEX);

    // Replace this with your remote button code
    if (code == 0x649BF708) {
      bulbState = !bulbState; // Toggle bulb state
      digitalWrite(RELAY_PIN, bulbState ? HIGH : LOW);
      Serial.println(bulbState ? "Bulb ON" : "Bulb OFF");
    }

    IrReceiver.resume();
  }
}

⚡ How It Works

The IR receiver detects signals from your remote.
The Arduino reads and decodes the signal into a unique hexadecimal code.
When it matches your chosen button’s code, the relay toggles, switching the bulb ON or OFF.

🧩 Ideas for Improvement

Once you’ve mastered this, try:

Using two buttons (one for ON, another for OFF).
Adding an LCD to show “Bulb ON” or “Bulb OFF.”
Controlling multiple relays for different devices.
Upgrading to a Wi-Fi module (ESP8266/ESP32) for mobile app control.

🏁 Conclusion

You’ve successfully created a remote-controlled bulb using Arduino!
You learned how to read IR remote codes and use them to switch a relay on and off.

This same method can be applied to control fans, lamps, or other appliances — bringing you one step closer to building your own DIY smart home system.

Tutorials