76480213
Jan 3, 2003
Nov 30, 2004
Cableless directional steering system for underground borehole drilling equipment comprising a hand held electronic operator's unit that communicates with a borehole drill guidance probe that is part of an underground electronic surface unit that interfaces with the operator, the hand held operator's unit used to determine the underground location of the guidance probe, in the field of underground borehole drilling
Electrical and Scientific Apparatus