A portable locator for detecting a buried object characterized by an electromagnetic (EM) field emission employing three-dimensional (3D) sensor arrays each having three substantially-identical EM field sensors disposed on a flexible annular wall having a radial centroid defining a sensing axis. The flexible annular sensors are retained in substantial concentricity with the corresponding sensing axes disposed in substantial mutual orthogonality. A pair of 3D sensor arrays disposed on a first axis substantially orthogonal to a second axis defined by another pair of EM field sensors each having a sensing axis disposed along the second axis. The locator introduces a user-reconfigurable user interface (UI) employing a “sticky” ratcheting audio UI and a hollow hinge assembly for redisposing the sensor assembly from an operating to a storage disposition.