User's Manual

Smart Systems User’s Manual Version 1.1

5.3.5 Depth Menu

This button cycles through 5 different depth ranges. The velocity of the material

determined under Calibration (Section 5.3.4) affects the total apparent depth scanned.

See Section 5.8.1 for more details about how depth is calculated.

The Depth units can be changed to metres, feet or time in nanoseconds. For details,

see Section 5.5.1 – Units. As well, all the Depth values can also be doubled or halved

by changing the Window Zoom option (see Section 5.5.1).

It is important to remember that the properties of the material control the actual

depth being scanned. Just because the Depth setting is set to a certain value, it

does not necessarily mean that the Noggin is able to penetrate to that depth and

collect data. For example, if the Depth setting is 5 meters but the material

penetration is only 3 meters the last 2 meters of the image will not contain

subsurface information. Some materials will absorb the Noggin signal and limit

penetration to less than the selected depth.

If the depth setting is deeper than the Noggin signals penetrate, the data in the lower

part of the section will look blank or speckled rather than signal with continuity.

5.3.6 Gain Menu

The signals that the Noggin system collects from the ground can be very weak,

especially from deeper objects. To see these weak signals it is necessary to amplify or

apply “gain” to them.

The Gain setting controls how much the signal is amplified. It varies from 1 to 9 with 1

the lowest and 9 the highest. In general, if the target is relatively shallow (1-2 meters) a

low gain value can be used. If the target is deeper or if the screen seems to be blank or

speckled in the lower part of the data section, increase the gain setting. Remember,

however, that if the Noggin signal is not penetrating to the maximum depth setting, even

the maximum gain setting will not show any data.

Figure 5-7 shows the effect of the gain setting. The data on the left has a gain of 1

incrementing to the right up to a gain of 9.