The hand-held GEM-3 uses the same electronics and firmware as our GEM-2 ski, so its features and options are comparable. Because it is comfortable to carry and has a field-swappable battery, extended surveys are no problem.
It is available with 3 different diameters of sensing head: 30, 40 and 65 cm. The larger diameters provide more moment for greater depth penetration, while the smaller diameters are better for localization and target discrimination.
Depending on the model, it can use up to 10 simultaneous frequencies from 30 Hz to 93 kHz.
The GEM-3 configuration can be built as a GEM-3 array. The GEM-3 Array is a flat panel with a large transmitter coil along its perimeter and 3 , 5 or 7 equally-spaced receiver coils along its center line. This configuration provides the best of both worlds: a wide swath for fast area coverage, with the resolution of a smaller receive coils.
The GEM-3 array can be mounted to a cart for towing by a small ATV. It can also be mounted on a sled, mounted directly to a vehicle or used in stationary applications.
The system can provide a real time map showing potential targets on the screen. The unit comes with a GPS unit at decimeter accuracy. The system can merge data from other sensors and devices on the same platform using standard serial communication lines.
The array has the following advantages:
◇ Maximum possible transmitter moment for a given array size
◇ Broadband operation, typically 10 frequencies between 30Hz to 93kHz
◇ Multiple receiver channels operating simultaneously;
◇ High-speed survey with high data density
◇Easy shipping owing to its flat construction
