urned on, which can cause the calculation to be off by many miles. For example, if you last used the GPS at 500 feet in elevation and then travel to 5,000 feet and turn it on again and use it in 2D, the read-out could be more than a HUNDRED miles off. So either input your new, known elevation or wait till you get 3D mode.
- Signals can be blocked by solid obstacles, like trees, buildings and cliffs or canyon walls.
- Extreme temperatures can slow down the GPS or make the screen fade. In very cold weather, keep it in your jacket.
- Because your GPS is calculating a distance across the surface of a datum (to be discussed in another article) like that on a map, GPS distances can be off when calculated for a slope.
- Operator error is the biggest GPS "problem." Too many people become "out of the box users," not practicing with the technology before using it--and relying on it--in the backcountry. Keystroke errors are also quite common, with an error potentially causing a discrepancy of hundreds or thousands of miles.
While Your GPS Should Come With A User's Manual
Whether you are climbing a glacier, orienteering in the backcountry, or on an easy day hike, Mike and Bob Burns cover all the latest technology and time-tested methods to help you learn to navigate-from how to read a map to compasses and geomagnetism.
Another GPS How-To
This book below (by Steve Hinch) focuses only on the GPS.
Starting with essential definitions such as UTM coordinate systems, position formats, and map datums, and moving on to creating "waypoints," and using your GPS with a computer, long-time GPS instructor Stephen W. Hinch breaks down the jargon and teaches you what you really need to know.
Up Next in the How-To Series....
- How To Use A GPS: Coordinate Systems and Datums
When you use a GPS, it's important to not only have an understanding of how the unit works and receives the information it provides but also the languages it speaks.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
Questions & Answers
© 2009 Deb Kingsbury