Vivax Metrotech vLoc3-5000 - Classic Locating Modes (Response); Peak Response Mode; Broad-Peak Mode; Null Mode

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2 vLoc3-5000 Receiver
2.6 Classic Locating Modes (Response)
The vLoc3-5000 receiver has an array of six antennas, and these can be toggled through different configurations (modes) to
provide different responses to the signals radiating from buried utilities. The modes are:
2.6.1 Peak Response Mode
Two horizontal antennas provide a “Peak” or maximum signal response over the center of the
buried line. The compass (line direction indicator) aligns itself parallel to the direction of the cable
together with a line position indicator showing which side of the line the locator is (available in
Active modes).
This is an accurate method of the locating as both horizontal antennas are used to provide a
clearly identifiable “Peak”. It is also less prone to the effects of signal distortion.
A Peak Level Indicator is also provided on the bar graph. This indicates the largest signal detected
allowing the user to quickly return to this point.
2.6.2 Broad-Peak Mode
This uses a single horizontal antenna and provides a “Peak” or maximum signal response over
the center of the buried line. The compass (line direction indicator) aligns itself parallel to the
direction of the cable together with a line position indicator showing which side of the line the
locator is (available in Active modes).
This gives a less defined peak than the twin horizontal antenna “Peak” mode – but is useful in
some situations such as deep lines because using a single antenna has the effect of boosting the
received signal.
2.6.3 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 together
with a line position indicator showing which side of the line the locator is (available in Active
modes).
The null mode works well in uncongested areas but is more prone to inaccuracies because of
field distortion. This effect can be utilised 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 “Null” mode. The arrows indicate the
direction to move the receiver to locate the position of the buried line.