System for locating multiple concealed underground objects

摘要

An improved locator system is provided which simultaneously couples a number of different frequency signals to a number of concealed underground conductive lines, for the purpose of locating and distinguishing between the underground lines. The locator system includes a transmitter which generates the different frequency signals for coupling to the underground lines. A receiver is also provided that detects the different frequency signals and distinguishes between the underground lines. The locator system further provides an arrangement for operating at virtually any frequency within the locating band, and for preselecting an operating frequency that avoids interference from extraneous signals.