March 3rd 12, 06:47 PM
posted to alt.internet.wireless,rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jun 2006
Posts: 1,898
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What's the most accurate elevation tool on the net (freebie)
In rec.radio.amateur.antenna alpha male wrote:
What elevation tool do you use and how does it compare in accuracy?
I'm trying to do some antenna siting calculations ... and ... for
that ... I need elevation information.
However ... given any set of coordinates ... e.g., Mt Hamilton,
California at coordinates 37.337408,-121.644073 ... I find the following
elevation tools all give DIFFERENT elevations (some are off by more than
a hundred feet!)
1. Google Map API yields 1217.061889648438 meters (3992.985 feet)
http://maps.googleapis.com/maps/api/elevation/json?
locations=37.337408,-121.644073&sensor=false
2. Geoplaner yields 1217.1 meters (3993 feet)
http://www.geoplaner.com
2. Daftlogic yields 1230.988 meters (4038.676 feet)
http://www.daftlogic.com/sandbox-goo...d-altitude.htm
4. Earthtools yields 1210 meters (3969.8 feet)
http://www.earthtools.org
5. Heywhatsthat (SRTM db) yields 1213 meters (3980 feet)
http://www.heywhatsthat.com/profiler-0904.html
Q: Which elevation tool do you use ... & what's the accuracy?
GPS 3 meter error
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