Earth Quake Alarm Circuit

Here is a simple project called earth quake alarm circuit. This circuit is divided into two sections.

1. Geo mechanical detector (Earth quake sensor)
2. Alarm circuit

The earth quake alarm circuit is based on the principle that earth quake create slow and suddenly vibration. In order to detect this vibration geo mechanical detector is used. The construction of geo mechanical detector is shown in figure 2.

Alarm Circuit | Earth Quake Alarm Circuit

The alarm circuit is built around dual input, 4 NAND IC (CD4011) and a NPN transistor. Input of NAND gate 1 (pin 1) is connected to sensor through probe 1, where NAND gate 2 configured in monostable multivibrator mode. NAND gate 3 and 4 is used as audio oscillator. The output form NAND gate 4 (pin 11) is given to base of speaker driver transistor T₁ through coupling resistor R₄.

The complete circuit can be kept in cabinet with 9V power supply. The geo mechanical detector where non on can disturb.

Check out other Earthquake Sensor and alarm circuit posted in bestengineeringprojects.com

1. Earthquake detector | Indicator Circuit using Vibration Sensor
2. Earthquake Detector using Arduino

PARTS LIST OF EARTH QUAKE ALARM CIRCUIT

Resistor (all ¼-watt, ± 5% Carbon)

R1 = 100 KΩ R2 = 2.2 MΩ R3 = 10 KΩ R4 = 680 Ω

Capacitors

C1 = 100 µF, 10V (Electrolytic Capacitor) C2 = 10 KPF (Ceramic Disc)

Semiconductors

IC1 = CD4011 (Quad 2-Input CMOS NAND Gate IC) T1 = BC147 (NPN General Purpose Small-signal Driver Transistor) D1 = 1N4148 (Silicon Switching Diode)

Miscellaneous

LS1 = 8 Ω speaker B1 = 9V PP3 battery PCB, screw, nuts, metal rod etc.