Thwart the attempt of a Bag snatching during journey. Keep this Tiny Alarm in your bag and it will beep loudly when somebody attempts to snatch your bag. It can protect your Laptop bag, Mobile pouch, Luggage etc during the journey. It is essentially a “Vibration Alarm” using ultra sensitive Vibration sensor SW 18020 P. So even a mild shake can activate the alarm. Build it and its cost is just Rs.50. Continue reading →
An Ultra sensitive Vibration SensorSW 18020 Pis now available from the Gaoxin. It can be used in different ways to sense mechanical vibrations to activate alarms and other surveillance systems and a variety of vibration detection projects.
The Vibration sensor has two electrical contacts which are not connected in idle condition. When an external force is applied due to movement or vibration , the Sensor’s contacts close. When the force is removed, the sensor terminal returns back to open contacts. The internal spring closes the contacts during vibration which triggers the circuit connected to it. Continue reading →
You can make a simple Knock Alarm using a Piezoelement. The Piezo element used in buzzers has a film of Piezoelectric material called Lead Zirconate Titanate. The crystals of this material generates around 1 volt when it is mechanically or thermally stressed. This principle is used to make this vibration sensor.