How to make your own earthquake detector

(x2) 741 OpAmps (Radioshack Catalog #: 276-007)

(x1) 9V Relay (Radioshack Catalog #: 275-005)

(xvar) jumper wires (Radioshack Catalog #: 276-102)

(x2) Heavy duty 9V battery clips (Radioshack Catalog #: 270-324)

(x2) 9V batteries (Radioshack Catalog #: 23-866)

(x1) Prototyping PCB (Radioshack Catalog #: 276-170)

(x1) Piezo Buzzer (Radioshack Catalog #: 273-080)

(x1) 5K Ohm Potentiometer (Radioshack Catalog #: 271-1714)

(x1) Potentiometer cap (Radioshack Catalog #: 274-415)

(x1) 470 Ohm Resistor (Radioshack Catalog #: 271-1317)

(x1) 3" diameter acrylic tube

(x1) Magnet (Radioshack Catalog #: 64-1888)

(xvar) lamp-pull ball-chain

Tools:

Solder

Soldering Iron

Wire Snips

Hot Glue Gun

I used a laser cutter to make my own personal enclosure, but one could easily modify a pre-made project enclosure to suit the needs of this project.