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Alarm Circuits

Simple Thermistor Based Fire Alarm Circuit

Last updated on 11 November 2025 by Admin-Lavi Leave a Comment

This Simple Thermistor Based Fire Alarm Circuit is very small, simple and smart. It uses a thermistor to sense heat fast. When temperature goes high the circuit wakes up and makes loud sound. No microcontroller, no complex parts. Only few components and we get a working fire alert that anyone can build at home Circuit […]

Filed Under: Alarm Circuits, Heater and Temperature Controllers, Sensors and Detectors

Fire Alarm Circuit using IC LM358

Last updated on 11 November 2025 by Admin-Lavi Leave a Comment

This Fire Alarm Circuit using IC LM358 is simple but smart. It uses a 10k thermistor and LM358 IC. It watches heat using a thermistor and makes buzzer ring when danger comes. This circuit is cheap and is good for home, school projects and safety demos. Circuit Working: Parts List: Component Value / Type Resistors […]

Filed Under: Alarm Circuits, Sensors and Detectors

MQ2 Gas Sensor Circuit with Arduino

Last updated on 9 November 2025 by Admin-Lavi Leave a Comment

The MQ2 Gas Sensor Circuit with Arduino is a low-cost sensor. It can catch bad gas in air very quickly. When we connect it with Arduino, we make small gas alarm system. It reads gas level, show number on LCD and buzzer make sound when gas goes high. This circuit is very simple to make […]

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

Gas Alarm Circuit using MQ Sensor and Buzzer

Last updated on 9 November 2025 by Admin-Lavi Leave a Comment

A Gas Alarm Circuit using MQ Sensor and Buzzer gives quick warning when gas level becomes dangerous. MQ Sensor senses gas leak fast and buzzer makes loud sound when gas is found. Circuit runs on 5V and uses very few parts. It is good for low-cost safety at home, kitchen and workplace. Circuit Working: Parts […]

Filed Under: Alarm Circuits, Sensors and Detectors

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

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Recent Posts

  • Simple Thermistor Based Fire Alarm Circuit
  • Fire Alarm Circuit using IC LM358
  • Smoke Detector Circuit using IC LM358
  • MQ2 Gas Sensor Circuit with Arduino
  • Gas Alarm Circuit using MQ Sensor and Buzzer

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