Image Number 2 for United States Patent #6653837.
A system includes a boring tool that is moved through the ground while transmitting a dipole locating signal such that the locating signal exhibits a pair of locate points at the surface of the ground. A local flux intensity of the locating signal is measured for at least one above ground point using a portable locator. A horizontal flux vector is established at that point, which is generally oriented in a horizontal plane, by using the measured local flux intensity to determine components of the locating signal in the horizontal plane that define the horizontal flux vector. The locator is moved in a direction generally defined by the orientation of the horizontal flux vector as at least an intermediate step in establishing the position of the nearest locate point. After moving, the procedure may be repeated to progressively converge on the nearest locate point.