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Get a recent latest version of GeoExplorerII® firmware Currently we have only one question and answer listed here. Please note that there is a new patch available for those still using Pathfinder Office™ 2.11. Click here to download. Information is provided below. For those still using Pathfinder Office 2.80, there are five patches available for this version. Click here to download them. Go to Trimble's Web site for additional Support Notes and helpful hints on the GeoExplorerII® Q. After collecting data for several hours, I downloaded my file. I performed differential correction and got a status report that said I only corrected 64% of my file. Can you tell me what went wrong? Webmaster's Note: Since this solution was posted in late 1999, Trimble has released a new software patch for Pathfinder Office™ v2.11. This results in creating Pathfinder Office™ v2.12. The patch fixes the above problem by automatically borrowing the IODE (Issue Of Data Ephemeris) records from the base file and inserting them into the rover file. Click here to go to the explanation or here to download the patch. By downloading and using this patch, you will not have to implement the solution below. A. There are a couple of things to look at. 1) Are you using a base station close enough to your project site? The recommended distance is no more than 300 miles (500Km) from your project site. It's possible that the rover (Geo) was "seeing" (using) satellites the base station could not see. 2) Is the Elevation Mask set at 15 degrees in your Geo? Lowering the Elevation Mask can make it easier to collect data but can also degrade the quality of your field data. In addition, it can allow the Geo to use satellites the base station cannot see, even if your base station is within the recommended distance limits. 3) Was your Geo sitting under your desk for a few days, weeks or months before using it in the field? If so, it was using an old Almanac. An Almanac is a data file that contains the rough, or general location, of all the satellites in the GPS constellation. This helps your GPS unit acquire satellites quickly. If your Geo hasn't been turned on in awhile and is still using an old Almanac, it will take a little longer to "find" satellites than usual. The big problem, though, is the Base and Rover must be using the SAME Almanac for differential correction to be 100% successful. What might have happened, is during differential correction in Pathfinder Office, the first part of the file may not have been corrected (while the unit was using the old Almanac), whereas the latter part of the file corrected successfully. As soon as the Geo had received a new Almanac (receiving satellite data continuously for 20-25 minutes), it was using the same Almanac as the Base, and therefore differential correction was successful. To prevent this last occurrence, let your GeoExplorerII "look" at the sky for 25 minutes while on the roof of your truck or on the roof of your building BEFORE you attempt to create a rover file and collect GPS data. This is extremely important, especially if you haven't used the unit for longer than a week. The Geo does not have to log data, just be exposed to as open a sky as possible. There is a way to fix this file, but it requires that you have the very first version of Pathfinder Office 1.0 or 1.10 or an older version of PFINDER. These versions have the original version of a program called the "SSF Editor." This program allows you to delete the old Almanac data from the rover file, then paste the current Almanac data from the base file you're using. It is a six step procedure. I have composed a document describing this process. I can email the document to you, as well as providing you with an copy of the older version of "SSF Editor." Send an email to request info.
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