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Over the last 60 years magnetometers have been credited with finding thousands of shipwrecks worth hundreds of millions of dollars. These super sensitive metal detectors, first used in WWII to locate and track submarines, have today become the workhorse of any serious marine search operation.
Magnetometers or "mags" are in use by a diverse group including professional treasure hunters, marine archeologists, commercial diving companies, law enforcement agencies, and military units. In addition to finding shipwrecks, mags are often employed to locate pipelines, anchors, sunken automobiles, weapons, and unexploded ordnance.These instruments locate shipwrecks and other lost objects by sensing changes in the earth's magnetic field. Any object made of iron or steel creates a disturbance in the field which the magnetometer can measure. A mag can detect a major disturbance, like the one created by a large steel wreck, at a distance of a quarter mile or more. This makes it theeal piece of equipment to use when searching a large area. Even old wooden wrecks, like Spanish galleons, have a "magnetic signature" created by the cannons, cannon balls, anchors, stoves, and other iron objects carried on board. Although the timbers have long since disintegrated, and valuable cargo is hidden under the sandy bottom, the powerful mag can detect the wreck's debris regardless of the material covering it.JW Fishers has specialized in the design and manufacture of magnetometers for over 20 years. Currently they produce two state-of-the-art mags, the Proton 4 boat-towed model and the Diver Mag 1, a hand-held unit carried by a diver. Both mags have visual and audio readouts. The Proton 4 features an easy-to-read LCD display that is backlit for night operations and an audio alarm to alert the operator when a target is encountered. The Diver Mag 1 has an LED display for easy underwater viewing and a waterproof earphone that lets the diver know a target is being detected. Both devices employ a unique triaxial noise-cancelling sensor which allows the mag to move in any direction without heading error or dead zone. A software package is available for the Proton 4 that allows the mag readout data, the boat's GPS position, and the track of the boat over the search area to be displayed and stored on a laptop PC.To receive a data sheet on Fishers marine magnetometers or a color brochure on all of their quality underwater search products contact:Christopher CombsJW Fishers Mfg. Inc.1953 County St.East Taunton, MA 02718, USAPhone: (800) 822-4744 or (508) 822-7330Fax: (508) 880-8949E-mail: firstname.lastname@example.orgWebsite: www.jwfishers.com