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BHC5 | Hydrophone String

The hydrophone string BHC5 is used to receive P-waves in water filled boreholes. The BHC5 consists of a downhole cable containing a Kevlar tension string and a number of moulded hydrophones at pre-defined intervals. Each hydrophone consists of a sensor with a pre-amplification board. The electronic boards are powered from the surface by a bank of rechargeable AA battery cells. The BHC5 amplifier boards are equipped with an internal test function to allow a quality check at any time. The test function outputs a synthetic signal on each channel where the amplification factors can be evaluated. The cable is terminated by a connector to the seismograph.