27-05-2017, 09:43 AM
An ultra sensitive earthquake detector circuit that can detect seismic vibrations. It can be used to detect vibrations on Earth. Therefore, it is an ideal device for monitoring incoming passages. The circuit exploits the direct piezoelectric property of the piezoelectric element used in the buzzers.
The lead zirconate crystals present in the piezoelectric element can easily store the current and can release the current when the orientations of the crystals are altered through mechanical vibrations. IC1 amplifies the signals of the piezoelectric element and the high output of switches IC1 in T1. When T1 leads, trigger 2 of the monostable (IC2) will be grounded to give 3 minutes of high output.
This high performance is used to sound the alarm and to turn on the LED. VR adjusts the sensitivity of the piezoelectric element. Attach the thin side of the piezoelectric element to the ground (if used as an incoming alarm) or inside a metal case (if used to bury the ground to detect vibrations in the ground).
Earthquake detector scheme:
![[Image: earthquake-detector.jpg]](http://www.electroschematics.com/wp-content/uploads/2009/11/earthquake-detector.jpg)
It can be understood in the following video:
