User's Manual

12-Survey & Map Mode Noggin
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Figure: 12-2 Effects of the Gain setting
Note that the gain setting is only for data display. The data are always saved without any
gain applied. It is not possible to collect Noggin
data with an “incorrect” gain setting.
If the user finds that they are always using very high or very low gain settings to see the data
adequately, the user may want to adjust the Linear Gain setting under Setup (see Linear Time
Gain on page 88).
12.2.7 Collecting Data using the Odometer
As the Smart System moves, the odometer triggers the system to collect a data trace at fixed
distance intervals. This interval is called the “station interval”. For the Noggin 250, the normal
station interval is 5 centimeters (about 2 inches). For the Noggin 500, the normal station interval
is 2.5 centimeters (about 1 inch). For the Noggin 1000, the normal station interval is 1.0
centimeter (about 0.48 inch). The station interval can be changed to a longer or short distance in
the Setup (see Station Interval on page 93).
Each data trace is plotted as a vertical strip on the screen (see Figure 12-1). The width of this
strip can be changed to 1, 2, 4, or 8 pixels (see Plot Interval on page 96). The normal trace width
for Noggin 250 traces is 2 pixels while the normal width for Noggin 500 and Noggin 1000 systems
is 1 pixel.
The odometer units that appear across the top of the screen can be set to either metres or feet
(see Depth Units on page 85).
Smart Systems can normally collect data at a very fast walking pace. However, if the system is
moved too quickly, data quality is reduced (see below).
During data acquisition, the current odometer position value (in the current units, either metres or
feet) is written to the lower left corner of the screen (see Figure 12-1).
Note that Smart systems can be configured to collect data either by pushing the system (forward)
or pulling the system (reverse). See Cart Direction on page 89 about changing the direction of
data acquisition.