When tracing a signal, adjust the signal level so that a high reading is indicated on the bar graph, but ensure the signal is not turned up so high that the bars are completely filling the screen.
When the maximum signal is detected, stop at this point and rotate the CAT so that the signal increases and decreases. The maximum signal is detected when the CAT is at right angles or directly across the buried utility.
If the detected signal is undistorted or no adjacent buried utilities are present, the signal drop-off on either side should be equal. When the signal is distorted or other buried utilities may be present, the drop of signal will be different on either side of the utility.