User's Manual

Smart Systems User’s Manual Version 1.1
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If units are metres then depths will appear in metres. If units are feet then depths will
appear in feet. Velocities appear in both metres per nanosecond (m/ns) and feet per
nanosecond (ft/ns). To change units see Section 5.5.1 - Units.
Selecting a Media
If a good hyperbola or a target of known depth is not available, the user will have to
estimate the velocity by selecting the predominant material in the area. This can be
done by selecting the MEDIA button and selecting one of the 8 choices. The velocity
associated with each of these choices is given in the following chart:
Material Velocity (m/ns) (ft/ns)
Very Dry Soil 0.170 0.558
Dry Soil 0.130 0.427
Dry Rock 0.120 0.394
Soil 0.100 0.328
Rock 0.100 0.328
Wet Soil 0.080 0.262
Wet Rock 0.080 0.262
Very Wet Soil 0.065 0.213
Input a Velocity Value
It is also possible to input a velocity value directly. When the Velocity button is selected
the user sees the current velocity and can use the up and down arrows to increase or
decrease that value. A table of typical radar velocities in various materials is given
below. If in doubt, use a value of 0.10 m/ns. This is a good average velocity that will
provide a good estimate of depth in most situations.
Material Velocity (m/ns) (ft/ns)
Air 0.300 1.000
Ice 0.170 0.558
Dry Soil 0.130 0.427
Dry Rock 0.120 0.394
Soil 0.100 0.328
Wet Rock 0.100 0.328
Concrete 0.100 0.328
Pavement 0.100 0.328
Wet Soil 0.065 0.213
Water 0.033 0.108
Velocities appear in both metres per nanosecond (m/ns) and feet per nanosecond
(ft/ns). To change units see Section 5.5.1 - Units.