Metal Detecting Theory - C-SCOPE EVO6000 User Manual

Metal Detecting Theory

How a Metal Detector Works
Metal detectors work by creating a magnetic field which stimulates electric currents in metal objects.
the metal detector measures the changes in the magnetic field caused by the currents. by analysing
the strength and timing of the currents the metal detector can estimate the depth and the type of
metal in a target.
the EVO6000 shows the depth on the right side of the display and the type of metal as a target id on
the large digits in the centre of the screen. the sensitivity level setting (SENSITIVITY) is used to filter
out weak signals which might be noise.
the volume of the low pitch tone the evo6000 makes when it detects iron targets is controlled by the
iron volume setting (IRON VOL). if you are not interested in digging iron targets, set the iron volume
setting (IRON VOL) low. Using an iron volume setting (IRON VOL) of zero will mute iron targets
entirely.
the EVO6000 lets you assign different tones to different target ids using the discrimination level
setting (DISCRIM). the volume of the medium pitch tone that the EVO6000 makes when it detects
targets with target ids above iron, but below the discrimination level (DISCRIM) is controlled by the
discriminate volume (DISC VOL). if you want to focus on targets with higher target ids, set the
discriminate volume (DISC VOL) low.
Ground Signals
The ground can also cause changes to the magnetic field. the effect of the ground on the magnetic
field changes with the level of mineralisation of the soil and on how close the ground is to the metal
detector search head. metal detectors use timing information and the rate of change of the magnetic
field to eliminate the ground signal.
The EVO6000 can automatically track and eliminate the ground signal (TRACKING). you can also set
the ground level yourself (GROUND) or have the EVO6000 calculate a ground setting for you to use
(AUTOSET). To help you spot when ground conditions have changed, the EVO6000 will tell you if the
tracking value it would have used is different from the ground level you have set.
Detection Modes
Metal detectors working in motion mode monitor the instantaneous changes in the magnetic field as
they pass over a target. motion mode is easier to use and set up because it is less sensitive to changes
in ground conditions. in motion mode a detector will detect a target only when the search head is
moving. even small movements of the search head are enough to make motion mode work.
Non-motion modes measure the level of the magnetic field relative to a baseline level. the baseline
level has to be reset when ground conditions change or in the presence of multiple targets. Non-
motion modes can find deep targets and do not require you to move the search head. Non-motion
modes are great for pin pointing targets and on sites where it is difficult to swing the search head.
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