(Creating the Circuit) The Advantage of the Inductive Coupler
We’re going to do a conductive locate on a cable TV amplifier (Figure 1) using 33 kHz (Figure 2) and locating in a southerly direction (Figure 3). Here’s where the three cables are located. After passing all three cables, this is the result for the westernmost of the cables (Figure 4). Notice the depth reading. The signal is going to follow the path of least resistance, but that path of least resistance doesn’t always go where we want it to.
With this conductive locate, the signal can go to earth through the ground rod, and it can choose to go down any or all of the five cables that leave this amplifier pad (Figure 5). Three cables go south, but none of them located particularly well. Peaks and nulls did not agree, and digital depth readings were illogical.
The use of an inductive coupler gives us an advantage over conductive locating in certain situations. Here, there are five cables as well as a ground rod (Figure 6). That means that a conductive locate can see the signal going six different directions.