CREATING A GEOID99.GGF FOR USE

G99DEF.EXE is a self-extracting zip file. By default, files will be unzipped to C:\GPSurvey\Data directory. You will also place the GEOID files you downloaded from the NGS Site in the same directory.

The Link below will get you to the NGS Web Site to download the PC version of GEOID99.

http://www.ngs.noaa.gov/GEOID/GEOID99/datageo99upc1.html

The above Link will connect you to the proper Web site location.  Depending on your Web Browser; you will see a Graphical and Non-Graphical Interface for GEOID99 Grid selection.
CAUTIONARY NOTE:
(When downloading the files from NGS choose Download PC version of Geoid 99) and follow the instructions below.
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STEPS TO FOLLOW:

1.  Launch GPSurvey

2.  Open a project in GPSurvey and select Adjust / Network and the
TRIMNET Plus Network Adjustment menu will be displayed

3.  Select the Geoid module and the Main menu will be displayed.

4.  Select Import New Geoid Model and then select Create New Global
     GGF File.

5. Select the source file. (These are the PC version GEOID99 grid files from the NGS Web Site)

	a.  The next screen will display the model name. 

6.  Select the interpolation method. 
	a. To do this, press the [*] (down arrow) key and highlight Spline. 
	b. Then press the space bar to toggle the selection to biquadratic.
NOTE: 
If you want to arrow a description, arrow down, enter a description, and press [Enter] to create the *.GGF file.

7.  The model is now loaded...... 
NOTE:
The new file will not become a part of the default selection found in the Load Geoid model menu.
Therefore, each time a new project is created, you will need to select Import New Geoid Model to select the
GEO99**.GGF files.


Additional Information:

This larger GEOID99 *.ggf file can then be used in Trimble Survey Office.  It can also be loaded into Grid Factory and smaller size Sub Grids can then be created to be loaded into the TSC1 Dataloggers running Survey Controller and Asset Surveyor