It really is hard to believe that metal detectors have been around for much longer than many people know. It was towards the end of the 19th Century that many scientists and engineers began to use their growing knowledge of electrical theory in order to develop a machine which would pinpoint the exact location of metal. Certainly the use of such an instrument would provide a huge advantage to any miner who was looking for ore bearing rocks. Then a German physicist by the name of Heinrich Wilhelm Dove invented the induction balance system which was incorporated in to the production of metal detectors 100 years later.
Many of the early metal detectors were crude and used a lot of battery power and they often only worked to a very limited degree. In fact Alexander Graham Bell used one in 1881 to try and locate the position of a bullet which was lodged in the back of the then American President James Garfield after his assassination.
However, the real development of the modern metal detector began in the 1930's when Dr Gerhard Fischer produced a system for radio direction finding and was used to accurately navigate pilots around the world. Although this system worked extremely well there were some anomalies noticed by Dr Fischer when over terrain that carried ore bearing rocks or metal was placed close to the system. He therefore reasoned that it should be possible to design a machine which would detect metal using a search coil resonating at a particular radio frequency. So in 1937 he applied for and was granted the first patent for a metal detector. He soon found that his designs were being put to a more practical use as they were used to help detect mines during the Second World War. Although they were heavy, consisting of a vacuum tube and required separate battery packs they worked and after the war many of the surplus mine detectors that were on the market were being purchased by relic hunters who not only used them for fun but for profit as well and so the hobby of metal detecting was born.
Soon more and more manufacturers were producing their own versions of the metal detector from the Oremaster Geiger Counter produced by Whites Electronics of California in the 1950's through to Charles Garrett who invented and produced the BFO (Beat Frequency Oscillator) metal detector (and Garrett's is still one of the world's leading designers of metal detectors today).
But it was during the 1950's and 1960's because of the invention and development of transistors that many metal detector designers and manufacturers were able to make smaller lighter machines with improved circuitry and were able to run on much smaller battery packs. They were even reduced to a size that a child would able to handle easily and many did. In fact there was such a huge requirement for these early models that Companies sprang up not just in the USA but in Britain as well hoping to supply the growing demand.
Even today the trend for metal detecting as a hobby still continues and the companies such as Garrett Metal Detectors and Fischer Metal Detectors are still producing new designs and models all the time.
J C Christian is an avid follower of metal detectors and how metal detectors work. He runs an informational site that follows Garret Metal Detectors, Fisher Metal DetectorsFisher Metal Detectors, Tesoro Metal Detectors, and Kellyco Metal Detectors just to name a few. Go to http://www.metal-detector-guides.com/ to find information to help with everything metal detecting.
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