®
Finding the Front Negative Locate Point (FNLP)
Locating
4.At the PLL, con- tinue walking away from the drill with the trigger held in; the signal strength
will decrease. When the “+” sign flips to a
| Plus |
| Changes |
| to Minus |
Surface of |
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Ground | Drill |
| FNLP |
Transmitter
Finding the Front Negative Locate Point (FNLP) from the Drill
5. To find the actual location of the FNLP, turn toward |
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the left so that the receiver is perpendicular (90°) to |
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the drill string and move the receiver toward the left |
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side of the drill string and, again, move the receiver |
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forward and backward until pinpointing the location |
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where the | Plus | ||||||||||||||||||
Mark this spot. |
| Changes | |||||||||||||||||
6. When the trigger is held in at the FNLP (and only | to Minus | ||||||||||||||||||
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the FNLP) the bottom window displays a prediction |
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of the transmitter’s depth as it would pass under the |
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FNLP, assuming no change in the pitch of the |
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transmitter. To distinguish the predicted depth from |
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the slant distance | (trigger released), the bottom |
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window will flash the predicted depth with a solidly |
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illuminated squiggle (“~”). For receivers that have |
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is not available. | (see “5.0 Series Firmware |
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Functions” in the Receiver Section) |
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RNLP
Fine Tuning
the FNLP
(Walking
Toward Left)
Drill
DigiTrak® Mark III Operator’s Manual | 47 |