Patent ID: 7345486

Claim:
In a technique for locating a boring tool which is within the ground, a method comprising: positioning no more than one single-axis transmitter for movement with the boring tool and for transmitting an electromagnetic locating signal; sensing at least one orientation parameter of the boring tool, using a sensor arrangement that is in electrical communication with the single-axis transmitter, to produce at least one orientation signal; modulating said electromagnetic locating signal using the orientation signal; transmitting the modulated electromagnetic locating signal; moving no more than one above ground portable locator, within a region containing a borepath of the boring tool, in relation to the boring tool while receiving said modulated electromagnetic locating signal therewith to generate at least one indication which provides for approaching the boring tool with the portable locator; establishing the orientation parameter of the boring tool as derived from the modulated electromagnetic locating signal; and generating a display on said above ground portable locator, responsive to the received electromagnetic locating signal, including said indication and said orientation parameter.