DCI DigiTrak Mark III, Руководство оператора

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Locating
®
7. Repeat steps 2 through 6 until the “+/–” signs flip from one to the other over a very small area. This is
either the FNLP or the RNLP. To find the other locate point, walk in the assumed direction of drilling.
If the signal strength increases you are at the RNLP; if it decreases you are at the FNLP.
8. To confirm you are over the FNLP or RNLP (as opposed to being over the transmitter), rotate the
receiver (with the trigger held in) 360° at the FNLP or RNLP. The signal strength should remain con-
stant during the entire rotation. If the signal strength changes significantly, you are not directly above
the FNLP or the RNLP.
Calculating Depth Based on Distance Between FNLP & RNLP
It is possible to estimate the transmitter’s depth should the information displayed in the depth/distance
window become unreliable. This is only possible if the pitch and negative locate points are reliable and
the ground surface is level.
To estimate the transmitter’s depth, first measure the distance between the FNLP and the RNLP. The
pitch of the transmitter must also be reliably known. Using the Depth Estimation Table below, find the
divider that most closely corresponds to the transmitter’s pitch. Then use the following formula to esti-
mate the depth:
Divider
RNLP and FNLP between Distance
Depth
=
For example, if the transmitter’s pitch is 34% then the corresponding divider value (from the table) is 1.50.
In this example, the distance between the FNLP and the RNLP is 11.5 ft (3.5 m). The depth would be:
7.66
1.50
ft 11.5
Depth
= =
ft or approximately 7.7 ft (2.35 m)
Depth Estimation Table
Pitch Divider Pitch Divider Pitch Divider Pitch Divider
0 1.41 26 1.47 52 1.62 78 1.84
2 1.41 28 1.48 54 1.63 80 1.85
4 1.42 30 1.48 56 1.64 82 1.87
6 1.42 32 1.49 58 1.66 84 1.89
8 1.42 34 1.50 60 1.68 86 1.91
10 1.42 36 1.51 62 1.69 88 1.93
12 1.43 38 1.52 64 1.71 90 1.96
14 1.43 40 1.54 66 1.73 92 1.98
16 1.43 42 1.55 68 1.74 94 2.00
18 1.44 44 1.56 70 1.76 96 2.02
20 1.45 46 1.57 72 1.78 98 2.04
22 1.45 48 1.59 74 1.80 100 2.06
24 1.46 50 1.60 76 1.82
52 DigiTrak
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Mark III Operator’s Manual