BHC4 Hydrophone String

The hydrophone string BHC4 is used to receive P-waves in water filled boreholes. The BHC4 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 cells. The cable is terminated by a connector to the seismograph.