On Sat, 03 Mar 2012 04:02:49 +0000, 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?

I'd use the info from another licensee's application, (on the same
tower). With the FCC you also must specify which survey you are using.
All towers over 200'(AIR) have their own entry in a tower database.