Grasscatcher Posted June 26, 2006 Share Posted June 26, 2006 Shouldn't the satellites shown as being visible at a particular time for a station location be the same "Numbers" as what the GPSr actually "sees" at that location and time? Quote Link to comment
+Timpat Posted June 26, 2006 Share Posted June 26, 2006 Shouldn't the satellites shown as being visible at a particular time for a station location be the same "Numbers" as what the GPSr actually "sees" at that location and time? Yes. I'm using my Trimble Pathfinder "GPS Pathfinder Office 2.70" desktop software and my session planner data reflects what I see displayed on my Map 60Cx right now. Not sure if another free version of this operates the same but it sure should. A few things to check first. You need the current Almanac from Trimble found here, called GPS Almanac is .SSF file format. Download this file and save it. Open a session and point to this current almanac file. The almanac should not be older than 30 days to be accurate. Next, be sure you have your correct location entered for your session. Finally, make sure you have the correct time zone for your location. (Adjust for daylight savings, etc.). If you can specify a narrow time frame it should then agree with your GPSr. Hope this helps answer your question. Quote Link to comment
Grasscatcher Posted June 26, 2006 Author Share Posted June 26, 2006 Ill try it and let you know . Quote Link to comment
Grasscatcher Posted June 26, 2006 Author Share Posted June 26, 2006 Shouldn't the satellites shown as being visible at a particular time for a station location be the same "Numbers" as what the GPSr actually "sees" at that location and time? Yes. I'm using my Trimble Pathfinder "GPS Pathfinder Office 2.70" desktop software and my session planner data reflects what I see displayed on my Map 60Cx right now. Not sure if another free version of this operates the same but it sure should. A few things to check first. You need the current Almanac from Trimble found here, called GPS Almanac is .SSF file format. Download this file and save it. Open a session and point to this current almanac file. The almanac should not be older than 30 days to be accurate. Next, be sure you have your correct location entered for your session. Finally, make sure you have the correct time zone for your location. (Adjust for daylight savings, etc.). If you can specify a narrow time frame it should then agree with your GPSr. Hope this helps answer your question. Timpat, Thanks ! It was the Almanac file. The "Current" Ephemeris file on the Planning Software page is NOT current in spite of it's name. Used your link and now everything agrees exactly. At the same time I downloaded the planning software , I downloaded the Current Ephemeris file, so that's where I got the almanac. I was using Lake City for a station. 38 03 lat, 107 18 lon, Sun 6/25, Elev cutoff 20 deg The time I was looking at was 3:30 pm Program said I should only be seeing G05,G17,G25 (due to high Position DOP) My GPSr was seeing 1,16,20,23. With "Your" almanac, program now says 1,16,20,23. Thanks again Quote Link to comment
+Timpat Posted June 26, 2006 Share Posted June 26, 2006 Glad it worked Grasscatcher and that I could be of help. Happy caching! Quote Link to comment
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