User's Manual

DIGITAL CONTROL INCORPORATED
DigiTrak F5 Operator’s Manual 27
Receiver Screen Tracking "On-the-Fly"
Actual Position of Receiver
and Transmitter
As the drill head advances, the FLP should travel along the receiver’s vertical crosshairs,
indicating that the tool is still on line. Once the FLP is in the box, hold the trigger in and
confirm that the predicted depth reading is as expected.
Off-Track Locating
The off-track locating technique is useful when it is not possible to walk above the transmitter
due to a surface obstruction or interference. Using the locate line’s perpendicular relationship
to the transmitter, it is possible to track the transmitter’s heading and also to determine if it is
maintaining its intended depth. The off-track locating method is only effective when the pitch
of the transmitter is 0% (0°) and traveling under flat ground.
To explain how the off-track locating method works, we will use the example of an obstruction
that is on the intended bore path, as shown in the figure below. The transmitter is about to go
under the obstruction.
1. Stop drilling and find the LL of the transmitter by putting the line in the box.
2. While holding the trigger in and keeping the receiver in the same orientation, step to
the side of the tool until you reach a predetermined distance (P1) from it. Move the
receiver forward and aft until you can see the ball jump from the bottom of the screen
to the top of the screen (or vice versa), then mark this location.