in the longitudinal direction by means of a spring pin terminating at the transmitter housing 13 is a rod linkage 15 which is bolted thereto on the other end of the transmitter housing 13 the transmitter housing 13 has a collector space 10 in which a pressure sensor 1 can be housed the pressure sensor 1 can be designed as one unit with a locating probe and a transmitter for wireless transmission of the measured or determined values of the pressure sensor 1 there are longitudinal slots 14 in the area of the collector space 10 in the transmitter housing 13 for wireless transmission by the transmitter the pressure sensor 1 is separated from the drilling fluid intended for flushing which is routed to the drill head 4 via a drilling fluid feed line 3 by means of a seal 2 the collector space 10 and thus the pressure sensor 1 has a fluid connection with the exterior compartment u2014 the drilling channel 6 via a bore 5 the fluid in the drilling channel 6 can thus enter the transmitter housing 13 via the bore 5 and a pressure sensor 1 is in contact with the fluid in the drilling channel 6 in order to measure that same pressure the bore 5 extends transversely with respect to the longitudinal direction of the transmitter housing 13 a filter 7 disposed between the bore 5 and the.