The BSS-02B is a borehole probe for measurement of magnetic susceptibility from 10-5 to 10-1 cgs. It is calibrated for 50mm diameter boreholes up to +90°C, and is able to operate at depths of up to 6000 metres over a temperature range of ambient to +120°C. The sonde can resolve strata as thin as 25mm, and will display a double response for layers thinner than 20mm. The operating frequency is 1.36 kHz.

The sonde comprises two sections: an aluminium alloy cylindrical enclosure containing electronic circuitry, and a high strength, non-magnetic enclosure in which the detector is located. The electronics enclosure must be surrounded by a pressure enclosure; this is usually provided by the client, to fit the rest of their system.

The sonde operates from an unregulated 15V nominal supply. It provides an output in the form of a three-wire CMOS serial interface (for integration into the client’s data acquisition system), and a single wire pulse rate output for use with rate meters and counters.