Choose a location that you feel is relatively clear of external magnetic fields. These may cause false triggering or reduced sensitivity respectively.
Turn the UFO detector right side up and apply power to the circuit. After one second the UFO Detector circuit will beep and the LED lights will begin flashing in a moving circular pattern to let you know it is in its detector mode. Once in its detector state, the UFO Detector will signal any magnetic or electromagnetic anomalies and any change it senses in our Earth’s magnetic field.
There are many ways to test the UFO detector. Once triggered the UFO Detector will continue to signal by flashing its LED and beeping until it is reset. If you used the mercury-reset switch, reset the circuit by turning the circuit upside down for a few seconds, then placing it right side up.
Test the UFO Detector by waving a magnet a few inches away from the detector. In addition to passing a magnet by the detector, one can obtain similar results by waving a ferrous material (like iron) close to the detector sensor as described for the magnet.
Other possible terrestrial triggers include external electromagnetic fields as discussed previously.
Resetting The UFO Detector
To reset the alarm, turn the UFO Detector upside down. This turns off and resets the circuit. Sometime the mercury will stick to the bottom electrodes in the switch even when the UFO detector is turned upside down and keep the circuit powered. Just tap or jiggle the detector a little to make the mercury fall.
It's normal to check the UFO Detector function every week or so when you first build it just to make sure it's working. I'm sure after a month or so, your confidence in the unit will be such that it will not be necessary to check the functionality. Once the circuit has been tested, it can be mounted inside a suitable housing.
UFO Detector Kit Page