The GeoMetrics G-816 Pushbutton Portable Magnetometer is a simple, low-cost instrument designed for field survey work. According to news releases, the basic G-816 system weighs only 1½ pounds, including, battery-powered console, sensor, cable and 8-foot aluminum staff, and offers 1-gamma sensitivity.
As a proton precession magnetometer, the G-816 reportedly offers absolute, drift-free measurements of total magnetic field, directly in gammas, anywhere in the world. Measurements are repeatable to the limits of sensitivity throughout the instrument's 20,000 to 90,000 gamma range. Measurements can be made in the field with no compensation for temperature drift, no setup for leveling, and no adjustments for orientation, field polarity or arbitrary reference levels. Each measurement is displayed on a 5-digit high-brightness numeric readout. Power is supplied by common D-cell flashlight batteries in an internal battery pack. Battery life is sufficient for more than 10,000 readings, with replacement signaled in advance by a flashing indicator light. For further information write GeoMetrics, 914 Industrial Ave., Palo Alto, California 94303.