This easy and Simple Entrance Alarm Circuit is made to protect door or way where people enter. It makes loud sound when someone walk through invisible IR light. It works good at day and night by not giving much wrong alarm. The circuit is simple and good for hobby people during nighttime. Circuit Working: Parts […]
Alarm Circuits
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Simple Smoke Alarm Circuit
This Simple Smoke Alarm Circuit is like house that has got a big nose. This circuit smells smoke in air and if smoke come it make loud alarm sound. Alarm can be buzzer, blinking light or it can be other alarm to start also. Smoke detector can work in different way one can use small […]
Simple Shadow Detector Security Alarm Circuit
This Simple Shadow Detector Security Circuit is like one guard with very sharp eyes. It uses one light sensor like photodiode to look shadow in one place. If something stop the light and make shadow then the circuit think someone is there and start an alarm. Alarm can be loud sound, blinking light or something […]
Simple Ultrasonic Security Alarm Circuit
Ultrasonic security alarm circuit work like invisible wall for ones home. It uses very high sound wave like tiny squeaky noise which human ear can not hear it uses this to find the movement. Think like circuit sends sound wave then it waits to hear echo come back. If someone walk in the way and […]
Simple Siren Circuit
Building a circuit that sounds like a real siren is made clear in this Simple Siren Circuit article! Similar to the siren of a police car or ambulance the sound rapidly rises and falls in pitch. Although this activity can be enjoyable keep in mind that sirens are also used in emergency situations. Circuit Working: […]
Simple Infrared Alarm Barrier Circuit
This circuit explains how to use invisible light to create a tripwire alarm. Think of it as a fence like beam of light. A loud alarm is sent off to warn of the presence of someone and to scare them away if they walk across the light and interrupt it. This is an enjoyable project […]