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Alarm Circuits

IR Burglar Alarm Circuit

Last updated on 17 October 2025 by Admin-Lavi Leave a Comment

Want to protect our home or room from intruders? This simple IR Burglar Alarm Circuit is our smart security buddy! It uses invisible IR light to sense any movement or break in the beam. The moment someone crosses the path, a loud buzzer alerts us instantly. Easy to build, with low cost and perfect for […]

Filed Under: Alarm Circuits, LED and Lamps

Arduino Based Motion Dog Barking Alarm Circuit

Last updated on 13 September 2025 by Admin-Lavi Leave a Comment

This Arduino Based Motion Dog Barking Alarm Circuit make dog sound when motion detects. it uses Arduino Nano, Pir sensor, Dog Sound Module, BC547 transistor, IC LM386 Amplifier Module and 8Ω Speaker. Pir senses human or animal move. Arduino play dog bark sound to scare intruder. This is simple and low cost security system. Circuit […]

Filed Under: Alarm Circuits, Arduino Projects, Sensors and Detectors

Luggage Safety Alarm Circuit using IC LM358

Last updated on 3 September 2025 by Admin-Lavi Leave a Comment

Today security is big problem everywhere. Many time thief try to open bag or suitcase in bus, train or station. We cannot always watch our luggage. This small Luggage Safety Alarm Circuit using IC LM358 help to protect our bag. It uses piezo sensor and LM358 to sense vibration. When someone touches or try to […]

Filed Under: Alarm Circuits, Security and Protection

Simple Wire Loop Security Alarm Circuit

Last updated on 23 August 2025 by Admin-Lavi Leave a Comment

Simple wire loop alarm is small security circuit. It uses thin wire as sensor loop. If loop is cut or opened the buzzer will sound. It works on 9V battery, needs few parts, is cheap and easy to make. Circuit Working: Parts List: Component Specification Qty Resistors 4.7M 1/4 watt 1 100k 1/4 watt 1 […]

Filed Under: Alarm Circuits, Security and Protection

Simple Refrigerator Door Open Alarm Circuit with IC 555

Last updated on 18 August 2025 by Admin-Lavi Leave a Comment

Sometimes people forget to close the fridge door. This causes loss of cooling and waste of electricity. To solve this problem we can use a Simple Refrigerator Door Open Alarm Circuit with IC 555 When the door is left open a buzzer sound comes to remind the user to close the door. This project uses […]

Filed Under: Alarm Circuits

Simple Shock Sensor Alarm Circuit

Last updated on 6 August 2025 by Admin-Lavi Leave a Comment

In this Simple Shock Sensor Alarm Circuit we can feel vibration or shock, which then makes loud sound with piezo buzzer. This circuit is easy to make and can be used at home, in car and in many places. It is good for security, stop theft and in feel movement. Main parts of the circuit […]

Filed Under: Alarm Circuits, Sensors and Detectors

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