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 […]
Alarm Circuits
Simple Siren Circuit
This Simple Siren Circuit article show how to make circuit sound like real siren! Sound goes up and down fast like police car or ambulance siren. Making this type of circuit is fun but remember siren are also used when emergency happens. Circuit Working: Parts List: Category Description Quantity Resistors 47k 1/4 watt 2 Capacitors […]
Infrared Alarm Barrier Circuit
This Infrared Alarm Barrier Circuit show how to use light which we cannot see to make tripwire alarm. It work like beam of light for small fences. When someone walk in front of light and break it, loud alarm make big noise to warn and scare person. It is fun project to do but real […]
Infrared (IR) Sensor Alarm Circuit using TSOP1738
This tutorial show how to make a Infrared (IR) Sensor Alarm Circuit using TSOP1738. It finds intruder using light which we cannot see. This alarm uses infrared light so people call it IR alarm. It make one invisible light beam with small chip named IC 555. If someone walk in front of light, then the […]
Infrared (IR) Intruder Alarm Circuit
This article tell how to make new type of Infrared (IR) Intruder Alarm Circuit. It can find person who walk through invisible light beam. Circuit have two main part: one transmitter and other one is receiver. Transmitter send out one infrared light beam across a room. If someone goes in front of light the LED […]
Simple Solar Powered Plant Watering Alarm Circuit
Simple Solar Powered Plant Watering Alarm Circuit tell us how to make small device that gives water to plant when plant need it. There are many ways to use solar energy but it should be clean and should not cost much. This device is mix of solar power and electronics which is very interesting. What […]