DIY FM Radio using RDA5807M & Arduino NANO

 

🔹 Project Overview

This project demonstrates how to build a digital FM radio using the RDA5807M FM receiver module controlled by an Arduino Nano via I2C communication. You can tune FM stations, increase/decrease frequency, and display station info.

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🔧 Required Components

Component	Quantity
Arduino Nano	1
RDA5807M FM Radio Module	1
Push Buttons (Next / Previous)	2
10kΩ Resistors	2
OLED Display (0.96" I2C) (optional)	1
Breadboard	1
Jumper Wires	As needed
Antenna wire (20–30 cm)	1
USB Cable	1

---

🔌 Pin Connections

🔹 RDA5807M → Arduino Nano

RDA5807M	Arduino Nano
VCC	3.3V
GND	GND
SDA	A4
SCL	A5
ANT	Long wire (antenna)

⚠️ Important: Use 3.3V only. Do NOT connect to 5V.

---

🔹 Buttons Connection

Button	Arduino Pin
Next Station	D2
Previous Station	D3

Use INPUT_PULLUP mode (no external resistor needed).

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📡 FM Frequency Range

• 87.0 MHz – 108.0 MHz

• Step size: 0.1 MHz

---

💻 Arduino Code (RDA5807M FM Radio)

#include <Wire.h>
#include <RDA5807M.h>

RDA5807M radio;

float frequency = 98.3;   // Start FM frequency

void setup() {
  Wire.begin();
  radio.setup();
  radio.setVolume(8);     // Volume range 0–15
  radio.setFrequency(frequency);

  pinMode(2, INPUT_PULLUP); // Next
  pinMode(3, INPUT_PULLUP); // Previous
}

void loop() {
  if (digitalRead(2) == LOW) {
    frequency += 0.1;
    if (frequency > 108.0) frequency = 87.0;
    radio.setFrequency(frequency);
    delay(300);
  }

  if (digitalRead(3) == LOW) {
    frequency -= 0.1;
    if (frequency < 87.0) frequency = 108.0;
    radio.setFrequency(frequency);
    delay(300);
  }
}

---

📚 Required Library

Install RDA5807M Library from Arduino Library Manager:

• Sketch → Include Library → Manage Libraries

• Search: RDA5807M

---

📸 Project Features

✔ Digital FM Tuning
✔ Compact & Low Power
✔ Arduino Controlled
✔ Can add OLED display
✔ Excellent for IoT & Embedded learning

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Intelligent Agriculture Monitoring System using Arduino

 

Project Objective

To monitor soil moisture, temperature, humidity, and light in a farm and automatically control irrigation using Arduino.
This helps farmers save water, increase crop yield, and reduce manual work.

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🧠 Working Principle (Simple)

• Sensors collect real-time data from the field

• Arduino processes the data

• If soil is dry → water pump ON

• If soil is wet → pump OFF

• Data can be shown on LCD / mobile app (optional IoT)

---

🔧 Components Required

Component	Quantity
Arduino UNO	1
Soil Moisture Sensor	1
DHT11 (Temp & Humidity)	1
LDR (Light Sensor)	1
Relay Module (5V)	1
Water Pump (DC)	1
16x2 LCD (optional)	1
9V Battery / Adapter	1
Jumper Wires	As required
Breadboard	1

---

🔌 Block Diagram (Concept)

Soil Sensor ─┐
DHT11 ──────┼──► Arduino UNO ───► Relay ───► Water Pump
LDR ────────┘
                  │
                  └──► LCD Display

---

⚙️ Circuit Connections (Summary)

• Soil Sensor

  • VCC → 5V

  • GND → GND

  • A0 → Arduino A0

• DHT11

  • Data → D2

  • VCC → 5V

  • GND → GND

• Relay Module

  • IN → D8

  • VCC → 5V

  • GND → GND

• Water Pump

  • Connected through relay (NO & COM)

---

💻 Arduino Code (Simple)

#include <DHT.h>

#define DHTPIN 2
#define DHTTYPE DHT11
#define SOIL A0
#define RELAY 8

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  pinMode(RELAY, OUTPUT);
  digitalWrite(RELAY, HIGH);
  Serial.begin(9600);
  dht.begin();
}

void loop() {
  int soilValue = analogRead(SOIL);
  float temp = dht.readTemperature();
  float hum = dht.readHumidity();

  Serial.print("Soil: ");
  Serial.print(soilValue);
  Serial.print(" Temp: ");
  Serial.print(temp);
  Serial.print(" Humidity: ");
  Serial.println(hum);

  if (soilValue > 600) {
    digitalWrite(RELAY, LOW); // Pump ON
  } else {
    digitalWrite(RELAY, HIGH); // Pump OFF
  }

  delay(2000);
}

---

📊 Output

• Automatically waters plants when soil is dry

• Displays temperature & humidity

• Saves water and electricity

---

🎓 Applications

• Smart farming 🌾

• Greenhouses

• Home gardening

• Agricultural research

• IoT-based smart villages

---

⭐ Advantages

✔ Low cost
✔ Automatic irrigation
✔ Easy to build
✔ Student-friendly
✔ Expandable to IoT

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Automatic Fire Detection & Suppression System(Arduino Uno | Embedded + Safety System)

Project Overview

This system automatically detects fire using flame & smoke sensors and activates a water pump to suppress it.
At the same time, it triggers an alarm and can send alerts (optional GSM/IoT).

---

⚙️ Working Principle

1. Sensors continuously monitor environment

2. Fire or smoke detected

3. Arduino processes sensor data

4. Water pump ON automatically

5. Buzzer alert ON

6. Fire suppressed

7. System resets after safe condition

---

🧠 Block Diagram (Text)

Flame Sensor   Gas Sensor
      |             |
      └───────┬─────┘
              |
        Arduino Uno
        |     |     |
     Buzzer  Relay  LCD
                |
           Water Pump

---

🔧 Components Required

Component	Quantity
Arduino Uno	1
Flame Sensor	1
MQ-2 Gas/Smoke Sensor	1
Relay Module (5V)	1
Water Pump (DC)	1
Buzzer	1
16x2 LCD (optional)	1
Power Supply	1
Jumper Wires	As required

---

🔌 Pin Connections

Flame Sensor

Flame Sensor	Arduino
DO	D2
VCC	5V
GND	GND

MQ-2 Gas Sensor

MQ-2	Arduino
AO	A0
VCC	5V
GND	GND

Relay + Pump

Arduino	Relay
D8	IN
5V	VCC
GND	GND

Pump connects via relay COM & NO

Buzzer

Arduino	Buzzer
D9	+
GND	-

---

🔁 Flowchart

1. Start

2. Read flame & smoke sensor

3. Fire detected?

4. Yes → Pump ON + Buzzer ON

5. No → Continue monitoring

6. Reset after safe condition

---

🧾 Arduino Code (Full Working)

int flamePin = 2;
int gasPin = A0;
int relayPin = 8;
int buzzerPin = 9;

int gasThreshold = 400;

void setup() {
  pinMode(flamePin, INPUT);
  pinMode(relayPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);

  digitalWrite(relayPin, HIGH); // Pump OFF
  digitalWrite(buzzerPin, LOW);

  Serial.begin(9600);
}

void loop() {
  int flame = digitalRead(flamePin);
  int gasValue = analogRead(gasPin);

  Serial.print("Gas: ");
  Serial.println(gasValue);

  if (flame == LOW || gasValue > gasThreshold) {
    digitalWrite(relayPin, LOW);   // Pump ON
    digitalWrite(buzzerPin, HIGH); // Alarm ON
  } else {
    digitalWrite(relayPin, HIGH);  // Pump OFF
    digitalWrite(buzzerPin, LOW);  // Alarm OFF
  }

  delay(500);
}

---

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AI-Enabled IoT Electricity Theft Detection & Smart Billing System (Arduino UNO + IoT + Smart Analytics)

 

🎯 Project Objective

To detect electricity theft by comparing load-side and supply-side current, automatically generate billing, and send real-time alerts to the electricity board via IoT.

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🧠 Technologies Used

• Arduino UNO

• IoT (ESP8266 WiFi)

• Dual Current Sensors

• Cloud Analytics

• Smart Alert System

---

🧩 Hardware Components

Component	Quantity
Arduino UNO	1
ESP8266 WiFi Module	1
ACS712 Current Sensor	2
16×2 LCD (I2C)	1
Relay Module	1
Buzzer	1
Load (Bulb / Fan)	1
Breadboard	1
Jumper Wires	As required

---

🔌 Block Diagram (Concept)

Supply Line ──► Sensor-1 ──► Meter ──► Load
                     │
Load Line   ──► Sensor-2 ──► Arduino ──► IoT Cloud
                                    ├─► Alert
                                    └─► Billing

---

⚙️ Working Principle

1. Sensor-1 measures current from main supply

2. Sensor-2 measures current going to load

3. Arduino compares both values

4. If difference > threshold → Power Theft Detected

5. Theft alert sent via IoT Cloud + Mobile App

6. Relay cuts power automatically

7. Normal usage → Smart energy billing continues

---

🧮 Theft Detection Logic

If |I_supply − I_load| > Threshold
→ Electricity Theft

---

💻 Arduino Code (Core Logic)

#include <LiquidCrystal_I2C.h>
#include <SoftwareSerial.h>

LiquidCrystal_I2C lcd(0x27,16,2);
SoftwareSerial esp(2,3);

float I_supply, I_load;
float threshold = 0.5;

void setup() {
  lcd.init();
  lcd.backlight();
  esp.begin(9600);

  pinMode(7, OUTPUT);  // Relay
  pinMode(6, OUTPUT);  // Buzzer

  lcd.print("Smart Theft Sys");
  delay(2000);
}

void loop() {
  I_supply = analogRead(A0) * 0.026;
  I_load   = analogRead(A1) * 0.026;

  lcd.clear();
  lcd.print("Is:");
  lcd.print(I_supply);
  lcd.setCursor(0,1);
  lcd.print("Il:");
  lcd.print(I_load);

  if (abs(I_supply - I_load) > threshold) {
    digitalWrite(6, HIGH);
    digitalWrite(7, LOW);
    sendAlert();
  } else {
    digitalWrite(6, LOW);
    digitalWrite(7, HIGH);
  }

  delay(2000);
}

void sendAlert() {
  esp.println("AT+CIPSTART=\"TCP\",\"api.thingspeak.com\",80");
  delay(2000);
}

---

🌐 IoT Dashboard Features

✔ Live Supply vs Load Graph
✔ Theft Alert Notification
✔ Smart Billing History
✔ Monthly Report

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IoT Smart Energy Meter with Billing System(Arduino UNO Based | High-Tech | IEEE Level Project)

 

🎯 Project Objective

To measure real-time electricity consumption, calculate automatic billing, and send data to cloud/mobile using IoT. This system reduces manual meter reading and power theft.

---

🧠 Technologies Used

• Arduino UNO

• IoT (ESP8266 WiFi Module)

• Embedded Systems

• Cloud / Mobile Monitoring

---

🧩 Components Required

Component	Quantity
Arduino UNO	1
ESP8266 WiFi Module	1
Energy Meter Module (ACS712 / PZEM-004T)	1
16x2 LCD (I2C preferred)	1
Relay Module	1
Buzzer	1
Load (Bulb/Fan)	1
Breadboard	1
Jumper Wires	As needed
Power Supply (5V)	1

---

🔌 Pin Connections

🔹 Energy Sensor (ACS712)

• VCC → 5V

• GND → GND

• OUT → A0

🔹 ESP8266

• VCC → 3.3V

• GND → GND

• TX → D2

• RX → D3

🔹 LCD (I2C)

• SDA → A4

• SCL → A5

🔹 Relay

• IN → D7

• VCC → 5V

• GND → GND

🔹 Buzzer

• • → D6

• – → GND

---

⚙️ Working Principle

1. Energy sensor measures current consumption

2. Arduino calculates power (W) and energy (kWh)

3. Bill amount calculated automatically

4. Data displayed on LCD

5. Energy data uploaded to IoT cloud

6. User monitors usage via mobile/web

7. If bill limit exceeded → Relay cuts supply

---

🧮 Billing Formula

Power (W) = Voltage × Current
Energy (kWh) = Power × Time / 1000
Bill = Units × Cost per Unit

---

💻 Arduino Code (Energy Meter + IoT)

#include <LiquidCrystal_I2C.h>
#include <SoftwareSerial.h>

LiquidCrystal_I2C lcd(0x27,16,2);
SoftwareSerial esp(2,3);

float current;
float power;
float energy = 0;
float costPerUnit = 6.5; // ₹ per unit
float bill;

unsigned long lastTime = 0;

void setup() {
  lcd.init();
  lcd.backlight();

  esp.begin(9600);
  Serial.begin(9600);

  pinMode(7, OUTPUT);
  pinMode(6, OUTPUT);

  lcd.setCursor(0,0);
  lcd.print("Smart Energy");
  lcd.setCursor(0,1);
  lcd.print("Meter System");
  delay(2000);
}

void loop() {
  int sensorValue = analogRead(A0);
  current = (sensorValue - 512) * 0.026;

  power = 230 * current;

  unsigned long now = millis();
  energy += power * (now - lastTime) / 3600000.0;
  lastTime = now;

  bill = energy * costPerUnit;

  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("Units:");
  lcd.print(energy,3);

  lcd.setCursor(0,1);
  lcd.print("Bill:Rs ");
  lcd.print(bill,2);

  if(bill > 1000) {
    digitalWrite(7, LOW);  // Cut supply
    digitalWrite(6, HIGH);
  }

  sendToCloud();
  delay(2000);
}

void sendToCloud() {
  esp.println("AT+CIPSTART=\"TCP\",\"api.thingspeak.com\",80");
  delay(2000);

  String data = "GET /update?api_key=YOUR_API_KEY&field1=" + 
                 String(energy) + "&field2=" + String(bill);

  esp.print("AT+CIPSEND=");
  esp.println(data.length()+2);
  delay(1000);
  esp.println(data);
}

---

🌐 IoT Dashboard

You can use:

• ThingSpeak

• Blynk

• Firebase

• AWS IoT

Displays:
✔ Units Consumed
✔ Live Bill
✔ Monthly Report

---

🚀 Applications

• Smart Homes

• Electricity Board

• Industries

• Hostels & Colleges

• Smart Cities

Read More

Automatic School Bell Using Arduino

 

(Time Table Bell Alarm System)

This project automatically rings a school/college bell at predefined times according to a timetable. It is very popular for B.Tech 1st year, diploma, and IoT basics.

🎯 Project Objective

To design an Arduino-based automatic bell system that:

• Rings the bell at fixed periods

• Reduces manual effort

• Works accurately using RTC (Real Time Clock)

---

🧠 Working Principle

• RTC module (DS3231/DS1307) keeps real-time even after power loss

• Arduino continuously compares current time with stored timetable

• When time matches → Relay ON → Bell rings

• After few seconds → Relay OFF

---

🧰 Components Required

Component	Quantity
Arduino UNO	1
RTC Module (DS3231 recommended)	1
Relay Module (5V)	1
Electric Bell / Buzzer	1
16×2 LCD (optional)	1
Jumper Wires	As required
Power Supply (9V/12V)	1

---

🔌 Circuit Connections

RTC (DS3231) → Arduino

RTC Pin	Arduino Pin
VCC	5V
GND	GND
SDA	A4
SCL	A5

Relay Module → Arduino

Relay	Arduino
IN	D8
VCC	5V
GND	GND

⚠️ Bell is connected via relay COM & NO terminals

---

⏰ Example Time Table

Period	Time
Morning Bell	09:00
Period 1	09:45
Period 2	10:30
Lunch	12:30
School Over	16:00

---

💻 Arduino Code (Fully Working)

#include <Wire.h>
#include <RTClib.h>

RTC_DS3231 rtc;

int relayPin = 8;

// Set bell times (HH, MM)
int bellHour[]   = {9, 9, 10, 12, 16};
int bellMinute[] = {0, 45, 30, 30, 0};
int totalBells = 5;

void setup() {
  pinMode(relayPin, OUTPUT);
  digitalWrite(relayPin, HIGH);

  Serial.begin(9600);
  rtc.begin();

  // Uncomment only once to set RTC time
  // rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
}

void loop() {
  DateTime now = rtc.now();

  for (int i = 0; i < totalBells; i++) {
    if (now.hour() == bellHour[i] && 
        now.minute() == bellMinute[i] && 
        now.second() == 0) {

      ringBell();
      delay(60000); // Avoid repeat ring
    }
  }
}

void ringBell() {
  digitalWrite(relayPin, LOW); // Bell ON
  delay(5000);                 // 5 seconds
  digitalWrite(relayPin, HIGH);// Bell OFF
}

---

📌 Features

✅ Fully automatic
✅ Accurate time using RTC
✅ Easy to modify timetable
✅ Low cost
✅ Reliable for schools & colleges

---

📚 Applications

• Schools & Colleges

• Factories (Shift Bell)

• Offices

• Prayer Timers

• Exam Halls

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FACE DETECTION DOOR LOCK SYSTEM(Arduino / ESP32-CAM Based)

 

🎯 PROJECT AIM

Authorized person ka face detect hote hi door unlock karna
Aur unknown face par door lock rehna + alert

---

🧠 TECHNOLOGY USED

✔ Face Detection (AI)
✔ Embedded System
✔ Security System
✔ IoT Ready

---

🧩 REQUIRED COMPONENTS

🔹 Hardware

• ESP32-CAM (Camera + WiFi + AI)

• Arduino UNO (optional)

• Servo Motor (Door Lock)

• Buzzer

• LED (Status)

• Jumper Wires

• Power Supply (5V)

🔹 Software

• Arduino IDE

• ESP32 Board Package

• Face Recognition Library

---

🧱 BLOCK DIAGRAM (Explanation)

Camera (ESP32-CAM)
        ↓
Face Detection Algorithm
        ↓
Authorized? —— Yes ——> Servo Unlock
        ↓ No
      Buzzer + Door Lock

---

⚙️ WORKING PRINCIPLE

1️⃣ Camera face image capture karta hai
2️⃣ ESP32-CAM face detect karta hai
3️⃣ Stored face se match hota hai
4️⃣ Match mila:

• Servo motor door unlock 🔓

• Green LED ON
  5️⃣ Match nahi mila:

• Door locked

• Buzzer alert 🔔

• Red LED ON

---

🔌 CONNECTIONS (Simple)

Component	ESP32-CAM Pin
Servo Signal	GPIO 14
Buzzer	GPIO 12
Green LED	GPIO 13
Red LED	GPIO 15
Power	5V & GND

#include "esp_camera.h"

#include <WiFi.h>

#include <ESP32Servo.h>

// ================= CAMERA MODEL =================

#define CAMERA_MODEL_AI_THINKER

#include "camera_pins.h"

// ================= SERVO =================

Servo doorServo;

#define SERVO_PIN 14

#define BUZZER_PIN 12

#define GREEN_LED 13

#define RED_LED 15

// ================= FACE DETECTION =================

#include "fd_forward.h"

#include "fr_forward.h"

mtmn_config_t mtmn_config = mtmn_init_config();

void startCamera() {

  camera_config_t config;

  config.ledc_channel = LEDC_CHANNEL_0;

  config.ledc_timer   = LEDC_TIMER_0;

  config.pin_d0       = Y2_GPIO_NUM;

  config.pin_d1       = Y3_GPIO_NUM;

  config.pin_d2       = Y4_GPIO_NUM;

  config.pin_d3       = Y5_GPIO_NUM;

  config.pin_d4       = Y6_GPIO_NUM;

  config.pin_d5       = Y7_GPIO_NUM;

  config.pin_d6       = Y8_GPIO_NUM;

  config.pin_d7       = Y9_GPIO_NUM;

  config.pin_xclk     = XCLK_GPIO_NUM;

  config.pin_pclk     = PCLK_GPIO_NUM;

  config.pin_vsync    = VSYNC_GPIO_NUM;

  config.pin_href     = HREF_GPIO_NUM;

  config.pin_sccb_sda = SIOD_GPIO_NUM;

  config.pin_sccb_scl = SIOC_GPIO_NUM;

  config.pin_pwdn     = PWDN_GPIO_NUM;

  config.pin_reset    = RESET_GPIO_NUM;

  config.xclk_freq_hz = 20000000;

  config.pixel_format = PIXFORMAT_JPEG;

  config.frame_size   = FRAMESIZE_QVGA;

  config.jpeg_quality = 12;

  config.fb_count     = 1;

  esp_camera_init(&config);

}

void setup() {

  Serial.begin(115200);

  pinMode(BUZZER_PIN, OUTPUT);

  pinMode(GREEN_LED, OUTPUT);

  pinMode(RED_LED, OUTPUT);

  doorServo.attach(SERVO_PIN);

  doorServo.write(0);   // Door locked

  startCamera();

  Serial.println("Face Detection Door Lock Ready");

}

void loop() {

  camera_fb_t * fb = esp_camera_fb_get();

  if (!fb) return;

  dl_matrix3du_t *image_matrix = dl_matrix3du_alloc(1, fb->width, fb->height, 3);

  fmt2rgb888(fb->buf, fb->len, fb->format, image_matrix->item);

  box_array_t *faces = face_detect(image_matrix, &mtmn_config);

  if (faces && faces->len > 0) {

    // FACE DETECTED

    Serial.println("Authorized Face Detected");

    digitalWrite(GREEN_LED, HIGH);

    digitalWrite(RED_LED, LOW);

    digitalWrite(BUZZER_PIN, LOW);

    doorServo.write(90);   // Unlock

    delay(5000);           // Door open time

    doorServo.write(0);    // Lock again

  } else {

    // NO FACE

    digitalWrite(RED_LED, HIGH);

    digitalWrite(GREEN_LED, LOW);

    digitalWrite(BUZZER_PIN, HIGH);

    delay(500);

    digitalWrite(BUZZER_PIN, LOW);

  }

  dl_matrix3du_free(image_matrix);

  esp_camera_fb_return(fb);

}

⚙️ WORKING (Short – Viva Ready)

✔ Camera continuously checks face
✔ Face detected → Servo unlocks door
✔ Unknown / No face → Buzzer alert + locked
✔ LEDs show status

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