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GEM-5B Array
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Data examples
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GEM-5 Poster ▪
Frequently asked questions
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GEM is a Registered Trademark
The GEM-5 array is a vehicle-mounted or vehicle-towed gradiometer sensor for rapid ground coverage. It has a transmitter in the middle straddled by two identical receiver coils below and above. The difference between the two receiver coils constitutes the signal. The gradiometer sensor has the following advantages:
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Ability to work as an array in which all sensors can operate simultaneously
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Immunity to noise induced by sensor motion
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Immunity to ambient environmental EM noise, and
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Increased signal-to-noise ratio (SNR) owing to the noise immunities.
GEM-5 Array Specifications
Programmable Operation
Swath: 210 cm (7 ft)
Dimensions (variable): 30cm x 50 m x 210cm
Coils configuration: Coaxial
Transmitter current: 20 amp RMS max
Transmitter moment: 180 Am2 at 270 Hz
Power supply: 12 VDC
Frequency range: 90 Hz to 96 kHz
Number of frequencies: 10-12
Sampling rate: 30 Hz
Output: Inphase and quad in ppm
Apparent conductivity
Magnetic susceptibility
Powerline amplitude
Realtime GPS input for navigation
Remote operation options – vehicle towed, for instance
Program upload and data download: WinGEM
Ppm to conductivity and susceptibility conversion
GEM-5 for utility detection
GEM 5 Array on an armored vehicle
for landmine detection
Geophex, Ltd. 605 Mercury St., Raleigh. NC 27603, USA; (919) 839-8515