In general, larger searchcoils will give better depth with larger targets and better ground coverage. However, sensitivity to smaller objects may be sacrificed. Smaller searchcoils will offer greater sensitivity to smaller objects and improved target separation in trashy soil. Be it out of sheer hobby or more on the professional level, you really would not perform well treasure hunting if you do not have a good metal detector to explore with.
A recent study proves that hand-held metal detectors are just as accurate as x-rays in finding coins and other metallic objects swallowed by children. They are cheaper and radiation-free, are usually lightweight, highly sensitive and require little maintenance. The special shape of the sensitive surface makes operation of the device easy, unlike portable metal detectors with ring transducers.
Metal detectors work on the principal of electromagnetism and their effects on conductive metals. The high-powered coil of metal, called the transmitter, uses the battery power to generate a penetrating magnetic field. As the electromagnetic field enters the ground, anything metallic will become charged with magnetism. Graduating from...