Abstract: A multi-frequency platform for metal detection is disclosed. The transmission frequencies may be selected by the user or in an autonomous fashion. Further, the weighting of the frequencies may also be selected, either by the user or in an autonomous fashion. The ability to select transmission frequencies and weighting of the frequencies provides expanded detection capability, both in terms of the types of targets being sought and the types of ground conditions being experienced.

Abstract: A non-invasive method and system for reliably locating underground pipes, particularly non-metallic pipes. The invention uses portable seismic generator to direct seismic waves into the earth at a downrange sampling location suspected to overlie a buried section of pipe. The seismic waves are imbued with a distinctive attribute, such as a predetermined frequency or digital pulse. Upon encountering the pipe, seismic waves are efficiently converted to longitudinal waves which are conducted lengthwise along the pipe to an accessible region. A receiver coupled to the accessible region is tuned to detect vibrations that carry the distinctive attribute. The receiver wirelessly transmits data indicative of the intensity of detected vibrations to a remote communicator which may be attached directly to the seismic generator. By sampling several locations in near vicinity, the most probable location of the buried pipe can be deduced.

Abstract: A metal detector includes a control housing electrically coupled to a search coil. The control housing includes a battery compartment having a first battery support surface located adjacent and a second battery support surface aligned at an angle relative to the first battery support surface to facilitate removal of a battery from the battery compartment. The metal detector also includes a movable door coupled to the control housing. The door is movable from a first, open position to permit access to an audio connector and a second, closed position covering the audio connector.

Abstract: A buried utility locator uses the “gradient method” to determine the depth of a buried, current-carrying utility. The method and corresponding apparatus used in said locator, to minimize field gradient measurement errors, includes first and second antennas. Both the first and second antennas are mounted along a common vertical axis inside the locator's housing. The first antenna is a gradiometer formed by two vertically spaced-apart magnetic field sensors connected in a differential configuration. The second antenna provides a secondary field measurement along the direction of the gradient sensor axes.