19-03-2014, 02:32 PM
A Homemade Metal Detector
Homemade Metal.docx (Size: 544.47 KB / Downloads: 20)
Introduction
A Calculator & Radio Metal Detector, as its name suggests, is made from a calculator and radio. You don't have to take anything apart or follow any complicated directions. All you’re going to do is tuning the radio, sticking the calculator on it and let the reaction happen. Nothing fancy, but it works!
Pre-knowledge
Metal detectors operate on the principle of magnetism. A metal detector will set up a magnetic field through a coil of wire and then direct this field down into the ground. Another circuit in the metal detector will "listen" to this field and emit a steady tone that you hear through a speaker.
When the coil is passed over the ground and a metal object comes in close proximity to this magnetic field, the tone will change pitch. This change in pitch means that you are close to a metal object.