Earthquakes are sudden and cannot be predicted when, where and how harmful it could occur.
so here is an instructable for how to make an "earthquake alarm" which could be very helpful especially at the time when people are sleeping .
this earthquake alarm cannot predict about the earthquake but can warn or notify you while the earthquake is hapenning.
Step 1: Material and Tools Required
-one relay (5v or 12v)
-one slide switch
-one 9v battery with connector
-one pcb standoff screw
- two screws 3mm and 1 nut
-one slide switch
-copper wire (38 swg , 1foot long)
-two red led (3mm)
-one zero pcb board
-solder and soldering iron
-iron sheet strip (0.5mm thick , 10cm x 1cm)
- one AA size cell
Step 2: Circuit Diagram (connetions)
this is the circuit connections for the earthquake alarm
Step 3: Pendumul Switch
-take the metal sheet (you can also use thick aluminium foil ) and cut 1cm wide strip about 10 cm long.
-now take the AA size cell and roll the metal strip to make a NINE (9) shape as shown in pictures.
-measure about 2 cm and cut the rest of strip (still maintaining the '9' shape).
-now take the pcb standoff screw and screw up the 3mm screw into it.
-take about 5cm of copper wire and make a loop shape by winding it on the standoff screw, after that solder it to make it fixed and conducting .
-now take the rest of copper wire and solder it to the loop on the standoff screw.
now with the help of screwdriver, make a hole on the pcb for the 3mm screw and fix the screw on pcb as shown in pictures
Step 4: Connections
-according to the circuit given, connect all the components together on the pcb.
-after all connections done , take the depron piece and stick it to the back of pcb with the help of glue gun.
now where to place it ?? , my suggestion is that you should stick it on the wall (where the pendulum is not affected by the flowing air or you can cover it up in a box and fix it on the wall )