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2 vLoc3 RTK-Pro Receiver
2.9.3 Null Mode
This uses vertical antennas, and provides a minimum or “Null” response over the center of the
buried line.
The compass (line direction indicator) aligns itself parallel to the direction of the cable (available in
Active modes).
The null mode works well in uncongested areas but is more prone to inaccuracies due to the effects
of field distortion. This effect can be utilized to detect the presence of distorted fields. Compare the
locate position “Null Mode” with the position “Peak Mode”. If the two positions do not coincide, this
indicates possible distortion. The greater the difference the greater the distortion.
Left/right indication arrows are also displayed when in the “Null” mode. The arrows indicate the
direction to move the receiver to locate the position of the buried line.
2.9.4 Delta Null
This uses dual vertical antennas. This has the advantage that it provides a sharper response than
the “null” mode and is less affected by distorted fields. All other functions are the same as the “Null”
mode.
2.9.5 Peak with Arrows Response Mode
The peak with arrows mode operates in the same way as the peak mode. It gives the largest meter
deflection when directly over the line. However, the left/right indication arrows are also displayed.
The arrows indicate the direction to move the receiver to locate the position of the buried line.
Note:
If the arrows indicated a different position for the cable than the peak bar graph position, this
indicates the possibility of a distorted field. Check by taking a depth reading on the ground and
then lift the cable locator a known distance such as 1m (3ft). If the depth does not increase by this
amount it confirms a distorted field and the data should be treated with caution.
2.9.6 Omni Peak Response Mode
When you see the two double-ended arrows around an icon, this means that the line is detectable
regardless of locator blade orientation. It is very useful for quickly checking an area for buried
lines using a grid search as one sweep will catch all locatable lines. In the classic screen the Omni
feature is available in the “Peak” and “Broad peak” modes.
