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Simple Infrared Fire Alarm Circuit

Last updated on 1 December 2025 by Admin-Lavi Leave a Comment

This is Simple Infrared Fire Alarm Circuit for beginners. It use infrared receiver sensor to detect fire heat or flame light. When fire come close sensor output changes. Then LED glow and buzzer makes sound. This circuit is cheap and easy to make. It also use only few parts like BC547 transistor, LED, buzzer, IR […]

Filed Under: Alarm Circuits, Sensors and Detectors

Laser Light Alarm Circuit using Arduino

Last updated on 27 November 2025 by Admin-Lavi Leave a Comment

This article is for simple Laser Light Alarm Circuit using Arduino. A laser light shines on an LDR. When someone blocks the laser beam, the LDR changes its value. Arduino reads this change and turns ON the buzzer to make alarm sound. A reset button stops the alarm. The system is low cost and easy […]

Filed Under: Alarm Circuits, Arduino Projects, LDR Circuits, Security and Protection

Laser Security Alarm Circuit using LDR and BC547 Transistors

Last updated on 27 November 2025 by Admin-Lavi Leave a Comment

This project is for Laser Security Alarm Circuit using LDR and BC547 Transistors. It uses LDR, two BC547 transistors, one diode and a buzzer. When laser light breaks an alarm rings. Circuit is cheap and very easy to build. Good for door security, box security and drawer protection. Circuit Working: Parts List: Component Value Quantity […]

Filed Under: LDR Circuits, Security and Protection, Transistor Circuits

Simple Sound Sensor Circuit with Arduino

Last updated on 25 November 2025 by Admin-Lavi Leave a Comment

This project show how to use sound sensor with Arduino. Sound sensor detect clap or loud voice. When sound come, Arduino turn ON LED and buzzer. This project for Simple Sound Sensor Circuit with Arduino help beginner understand sensor working. Arduino Coding: Code Explanation: Circuit Working: Parts List: Item Quantity Resistors 220Ω 1/4 watt 1 […]

Filed Under: Arduino Projects, Sensors and Detectors

Arduino and Joystick LED Controller Circuit

Last updated on 25 November 2025 by Admin-Lavi Leave a Comment

This project shows how to control many LEDs using one joystick and Arduino. The joystick moves in X and Y direction. Arduino reads this movement and turns ON or OFF the LEDs. This Arduino and Joystick LED Controller Circuit is simple to build. Good for beginners and Arduino lovers. Arduino Coding: Coding Explanation: Circuit Working: […]

Filed Under: Arduino Projects, LED and Lamps

Measuring Bend Angle using a Flex Sensor Circuit

Last updated on 24 November 2025 by Admin-Lavi Leave a Comment

Flex sensor is a small strip that changes resistance when we bend it. When straight, resistance is low. When bent, resistance becomes high. Many projects use this sensor. It is used in robots, gloves, gaming, medical tools and wearables. Sensor works simple with more bend gives more resistance. Flex Sensor Output Voltage Comparison Graph: Circuit […]

Filed Under: Sensors and Detectors

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