Anyone notice GPS errors

Hi,
I went for a hike yesterday with my Droid using OruxMaps to record my trail. The terrain was hilly (Big Basin State Park in CA) with some heavy forest, some clear areas on the tops of the hills. I was on trails and roads marked on the map so I could easily check if the position was correct. It wasn't for large parts of the hike! It sometimes was correct, especially in the canyons under deep forest, but it was off (maybe 500 feet) for long periods of time when I on the ridges under clear skies. There is no phone service there so I had the phone in airport mode for the whole time to conserve batteries. Maybe that was the problem.
Jon

hikerjon wrote:Hi,
I went for a hike yesterday with my Droid using OruxMaps to record my trail. The terrain was hilly (Big Basin State Park in CA) with some heavy forest, some clear areas on the tops of the hills. I was on trails and roads marked on the map so I could easily check if the position was correct. It wasn't for large parts of the hike! It sometimes was correct, especially in the canyons under deep forest, but it was off (maybe 500 feet) for long periods of time when I on the ridges under clear skies. There is no phone service there so I had the phone in airport mode for the whole time to conserve batteries. Maybe that was the problem.
Jon

Hi, Jon;

Please, read this -->https://oruxmaps.forumotion.com/improvements-f11/fix-for-gps-on-droid-x-t513.htm?highlight=droid

orux

Hi Orux,

I think my problem is different. The original map was a USGS map in datum NAD 1927. I converted it from Oziexplorer to Orux using OruxDesktop. I think the datums are confused. It acts like it is using WGS84.

hikerjon wrote:Hi Orux,

I think my problem is different. The original map was a USGS map in datum NAD 1927. I converted it from Oziexplorer to Orux using OruxDesktop. I think the datums are confused. It acts like it is using WGS84.

Hi;

Could you send me the .map + image file _-> oruxuro@gmail.com

You can check if the calibration is correct, using the map and an online source:

Load the map, scroll to a well know point (a road, peak,....). Then change to google earth map. You should see the same point.



orux

Thanks for the tip. This allows me to easily check the accuracy. When I ran oruxdesktop to convert from Oziexplorer it did not recognize the datum. So I chose WGS84. This was wrong. When I chose North America 1927 CONUS the map was more accurate. Here is the line from the Oziexplorer .map file:
OziExplorer Map Data File Version 2.2
Franklin Point
FranklinPoint.jpg
1 ,Map Code,
NAD27 CONUS,WGS 84, 0.0000, 0.0000,WGS 84