A testing unit for testing a device under testDUT comprises a signal generator for applying a stimulus signal to the DUT, a receiving unit for receiving a response signal from the DUT on the applied stimulus signal, and a synchronizing unit for synchronizing a data flow of the response signal between the DUT and the receiving unit. First arrivals to a plurality of receivers are picked and used to estimate a normal-moveout velocity. At least one field report is generated based on the certain information to characterize at least one of an inground operation, an operational condition of the downhole transceiver, an operational condition of the uphole transceiver, and an operational condition of the drill rig. The electrodes’ arrangement is configured for defining multiple spaced apart locations for collecting electrically charged particles emitted from said source of charged particles. The process includes the sequential steps of individually and simultaneously drawing and texturing a plurality of singles yarns; converging the drawn and textured singles yarns through an air jet entangler that simultaneously entangles and tensions the yarn bundle; twisting the singles yarns in the yarn bundle about each other in alternate, or otherwise patterned, S and Z directions.