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Long Range Locator
A long-range locator is a class of fraudulent devices purported to be a type of metal detector, supposedly able to detect a variety of substances, including gold, drugs and explosives; most are said to operate on a principle of resonance with the material being detected. Theory of operation Skeptics have examined the internals of many such devices and found those that have been examined to be incapable of operating as advertised, and have dismissed them as overpriced dowsing rods or similarly useless devices. Virtually all such devices claim to operate on a resonance, resonant frequency principle where the device is said to emit an electromagnetic signal, either through an antenna or a probe, that will respond to a specific substance such as gold, silver, or sometimes even paper money, and that the device will indicate the presence of such material by indicating a change in direction relative to the operator. This theory of operation is not supported by scientific theory; the devi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal Detector
A metal detector is an instrument that detects the nearby presence of metal. Metal detectors are useful for finding metal objects on the surface, underground, and under water. The unit itself, consist of a control box, and an adjustable shaft, which holds a pickup coil, which can vary in shape and size. If the pickup coil comes near a piece of metal, the control box will register its presence by a changing tone, a flashing light, and or by a needle moving on an indicator. Usually the device gives some indication of distance; the closer the metal is, the higher the tone in the earphone or the higher the needle goes. Another common type are stationary "walk through" metal detectors used at access points in prisons, courthouses, airports and psychiatric hospitals to detect concealed metal weapons on a person's body. The simplest form of a metal detector consists of an oscillator producing an alternating current that passes through a coil producing an alternating magnetic field. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
