Author Topic: How To Use A GPS: Coordinate Systems and Datums  (Read 846 times)

TheGUYuk

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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." If we don't truly understand these languages and how, why, and when to change from one to another, a GPS can end up being more of a hindrance than a help.
 
 What it comes down to is that relying on a gadget we don't understand can get us into trouble. When we're talking about using a GPS, trouble means getting lost.
 
 So in this second article in a series, I'll cover the basic principles of coordinate systems and map datums and how they relate to GPS use. This is intended to be an introductory overview, so I'll direct you to some additional reading material on these topics in case you want to learn more and get even more out of your GPS.
 
http://www.squidoo.com/GPS-coordinate-systems-datums
 
Enjoy O0

TheGUYuk

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Re: How To Use A GPS: Coordinate Systems and Datums
« Reply #1 on: 17:56:14, 08/10/12 »
What is a GPS Waypoint?
 

 What is a GPS Waypoint?written by: Daniel P. McGoldrick   • edited by: Rhonda Callow• updated: 2/8/2010A waypoint is a term you need to know in order to most effectively utilize and navigate with a portable, handheld GPS device whether you’re using it for hiking, geocaching, fishing, or any other outdoor activity. Find out what you need to know about waypoints below.
  • slide 1 of 2The Importance of WaypointsAre you wondering what a GPS waypoint is because you’re new to the world of portable, handheld GPS devices and their capabilities? Garmin Topo Then let’s get right to a good working definition and explore all the ramifications regarding the significance of these navigational tools. The term has been around since the revolutionary handheld GPS devices first became available to the public and was no longer the exclusive [size=100%]domain[/size] of the military. A waypoint is a physical location somewhere on our planet as determined by the satellites up there in the stratosphere designed for the purpose of communicating location data to a GPS receiver. A waypoint is the set of coordinates representing the longitude and latitude of a given position. Older models would represent the coordinates of a waypoint with some code limited to four characters but now they allow for a more apt description such as “primitive camp site” for example.

  • http://www.brighthub.com/electronics/gps/articles/63503.aspx

  • TheGUYuk

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    Re: How To Use A GPS: Coordinate Systems and Datums
    « Reply #2 on: 18:00:43, 08/10/12 »
     
     
    Information on GPS navigation and
    other GPS applications
     Information on GPS navigation and
    other GPS applications
    GPS Navigation everywhereIf Navigation stands for "determining of position and direction on or near the surface of the Earth", than GPS Navigation stands for the same with the help of the Global Positioning System (GPS). A GPS chip is a small radio-receiver that can capture the signals of several GPS satellites simultaneously. This way it can compute its Position, Velocity and the exact Time. This information is given out in encoded form.

    How to use this information for navigation?
    http://www.gps-practice-and-fun.com/index.html

    Wurz

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    Re: How To Use A GPS: Coordinate Systems and Datums
    « Reply #3 on: 20:48:26, 10/10/12 »
    I think that the 1st article just confuses matters.  All you need to know is that by default a gps uses WGS84 and you need to use a local datum, typically in the UK for walking being OSGB and then use grid references.  There is a datum shift between the 2 systems which varies on your distance from the centre of the relative systems.  For the user all that matters is that you select the right one when you first turn on your GPS or use it in a different part of the world.

    DrNytol

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    Re: How To Use A GPS: Coordinate Systems and Datums
    « Reply #4 on: 22:36:12, 10/10/12 »
    Great post  :)  and perfectly timed after last weekends adventure
    114/214