User's Manual

DIGITAL CONTROL INCORPORATED
28 DigiTrak F5 Operator’s Manual
Preparing for Off-Track Locating
3. While still holding the trigger in and keeping the receiver in the same orientation, step
to the side of the tool another predetermined distance (P2) further away 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.
4. While still holding the trigger in and keeping the receiver in the same orientation, step
to the side of the tool another predetermined distance (P3) further away 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. Release the
trigger.
5. Connect points P1, P2, and P3 with a line. This is the locate line. Because the LL
runs perpendicular (at a 90° angle) to the transmitter when the transmitter is level, we
can determine the heading of the tool. By comparing the slant distance or signal
strength at the predetermined distances of P1, P2, and P3, as the tool progresses,
we can verify if the drill head is moving away from or maintaining the intended bore
path. It is important to track the pitch of the transmitter (see Locate Mode Screen on
page xxviii) to verify that the tool is maintaining the desired path.
6. As drilling continues, steer the tool to maintain a constant slant distance at each of
the points P1, P2, and P3. If the slant distance increases, the tool is moving away; if
the slant distance decreases, the tool is moving toward the side position.
LL
P2 P3P1
D
r
i
l
l
Bore path
Obstruction
Path around
obstruction
Predetermined
distances