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 […]
Alarm Circuits
IR Burglar Alarm Circuit
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 […]
Arduino Based Motion Dog Barking Alarm Circuit
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 […]
Luggage Safety Alarm Circuit using IC LM358
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 […]
Simple Wire Loop Security Alarm Circuit
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 […]
Refrigerator Door Open Alarm Circuit with IC 555
Sometimes, people forget to close the fridge door and 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 stays open, the buzzer gives a sound, so it reminds the user to close the door This […]