WinFrog User’s Guide - Appendix C – GPS/MX 9400
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Calculation:
Set the Calculation selection to Primary or Secondary. Devices set to Primary
calculation are used to provide a vessel position. Note that more than one Primary
positioning device can be added to a vehicle’s device list; data from these devices
will be combined in a weighted mean solution. (See the paragraph on Accuracy
below for more on the weighting of Primary calculation device data).
If the Calculation type is set to Secondary, WinFrog will simply monitor the device’s
data. WinFrog will not use the position data from the device in the final solution of
the vehicles’ position.
Note: In the case of Primary device failure, WinFrog will not automatically use the
Secondary devices for the vessel’s position computation. Instead, the vehicle’s
positioning will go to dead reckoning (if dead reckoning is turned on). You must
manually change a Secondary device to Primary in order for the data to be utilized.
Use For Heading Calculations:
Select this checkbox if the device is to be used in conjunction with another GPS
device for determination of the heading of the vessel.
Graphics:
If On is selected, a labeled square will show the raw (offset but unfiltered) location of
the GPS antenna in the Graphics and Bird’s Eye windows. This provides a means of
comparing raw device and filtered vehicle positions.
Elevation:
Setting the Elevation option to On will result in the elevation determined by GPS to
be used as the elevation of the vessel referencing the GPS (WGS84) Ellipsoid. The
sounder data recorded in WinFrog’s .RAW data files will not be affected.
This option is meant only for those applications where there is no fixed vertical
reference (i.e. mean sea level), such as on a river. For acceptable results, this option
requires the use of high accuracy “RTK” GPS data.
