Unlike the simple handheld detectors used to trace a wire, the electromagnetic pipe and cable line locator, used by a professional Service Locate technician, allows adjustment to a variety of radio frequencies proved necessary to locate metallic service lines in resistive as well as conductive soils. The Service Locate technician has the knowledge and experience to determine when radio frequencies need to be intermittently changed to improve the location of a pipe or cable line. From this determination of the technician proves his or her “competence” which in-turn brings “confidence” to the information gathered and the work completed.