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Alarm Circuits

Fire Alarm Circuit using IC LM358

Last updated on 29 June 2026 by Admin-Lavi Leave a Comment

This Fire Alarm Circuit using IC LM358 is simple but smart, as it uses a 10k thermistor and LM358 IC; also it watches heat using a thermistor and makes buzzer ring when danger comes. Additionally, this circuit is cheap and is good for home, school projects and safety demos. Circuit Working: Parts List: Components Value […]

Filed Under: Alarm Circuits, Hobby Circuits, Mini Projects, Security and Protection, Sensors and Detectors

Smoke Detector Circuit using IC LM358

Last updated on 29 June 2026 by Admin-Lavi Leave a Comment

This circuit is for simple Smoke Detector Circuit using IC LM358, as it uses MQ2 gas sensor to sense smoke; also it uses LM358 IC to compare sensor voltage. Therefore, when smoke is present the buzzer and LED turn ON and, in addition, this circuit is good for beginners. Circuit Working: Parts List: Components Quantity […]

Filed Under: Alarm Circuits, Hobby Circuits, Security and Protection, Sensors and Detectors

MQ2 Gas Sensor Circuit with Arduino

Last updated on 29 June 2026 by Admin-Lavi Leave a Comment

The MQ2 Gas Sensor Circuit with Arduino is a low-cost sensor, as 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. Also, this circuit is very simple […]

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

Gas Alarm Circuit using MQ Sensor and Buzzer

Last updated on 29 June 2026 by Admin-Lavi Leave a Comment

A Gas Alarm Circuit using an MQ Sensor and a buzzer gives a quick warning when the gas level becomes dangerous; also the MQ Sensor quickly detects a gas leak, and the buzzer produces a loud sound when it detects gas. Moreover, circuit runs on 5V and uses very few parts and it is good […]

Filed Under: Alarm Circuits, LED and Lamps, Security and Protection, Sensors and Detectors

Chirping Sound Buzzer Circuit

Last updated on 29 June 2026 by Admin-Lavi Leave a Comment

This simple circuit makes a normal buzzer produce a chirping or tweeting sound; it uses a 9 V battery, two push buttons, one capacitor, and a buzzer, also the circuit also does not need a microcontroller or IC. Also, it works on charging and discharging of capacitor and this Chirping Sound Buzzer Circuit is good […]

Filed Under: Alarm Circuits, Audio Circuits, Mini Projects

Make Sound with Arduino using Buzzer Circuit

Last updated on 29 June 2026 by Admin-Lavi Leave a Comment

This project shows how to Make Sound with Arduino using Buzzer Circuit; also buzzer makes sound when we send signal from Arduino pin. Here, we can use it for alarms, alerts, or simple tones; moreover, we use two versions here: one with individual components and another with a buzzer module. Arduino Code: Code Explanation: Parts […]

Filed Under: Alarm Circuits, Arduino Projects, Audio Circuits, Mini Projects

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