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Your unit display will indicate whether you are in 2D or 3D mode. If it's displaying 2D, try moving around and getting into a more open area, free of obstacles like tall trees, to hopefully get to 3D mode if at all possible.
**You should always check your "EPE" or "Estimated Position Error," which will display on your GPS, usually right on the same screen that indicates how many satellites it's communicating with--the satellite page. This will also show you how accurate, or perhaps inaccurate, the position fix is. An EPE of 20 feet or less is good. The lower the EPE the better.
A Word On Satellite Configuration
And why it matters
Where in the sky the satellites your GPS is communicating with are located relative to where it -- and you -- are located is important when it comes to the accuracy of the information the unit will provide. And your handheld unit will display that configuration on the satellite page. Again, this is page where you can determine how many satellites the GPS is connecting or communicating with and the Estimated Position Error (EPE). So this is yet another piece of information right on one screen.
The satellite screen is the first screen you should use when you fire up your GPS.
The satellite configuration is usually depicted within two concentric circles on the screen, with the satellites represented by dots or numbers. The inner circle on the screen represents the sky more above you than to the sides. The outer circle represents the horizon.
If your GPS is connecting with four or more satellites and is in 3D mode, and your EPE is low, that means your position fix will be good. And a good satellite configuration is even better.
What you want to see, ideally, is that one or two satellites are overhead -- within that inner circle -- with the rest spread out around the sky, somewhere in that outer circle. If all of those satellite "dots" or numbers are in the outer circle, with none over head, try moving around and see if you can improve that configuration.
Buying The Right Handheld GPS
What to look for...
GPS units range from basic to complex, with a wide range of features, capabilities and prices from around $100 into the thousands of dollars, believe it or not. Me, I use fairly basic units, which do everything I need for Search & Rescue work and backcountry travel. I'll show you which units I use below.
But when it comes to choosing a GPS for yourself, think about what you want to use it for, where you'll be using it, and which features you really want and need, not to mention your budget. Features to consider might include:
- Weight and bulk--Where will you being carrying the unit? In a jacket pocket? A radio harness? In or on a backpack?
- Durability--Is it water-resistant or waterproof? It is dust-proof? How well can it handle extreme temperatures?
- Screen and text size--Can you see the text and numbers well enough?
- Data entry--Is it easy to enter information? How are the buttons laid out? Can it be used one-handed? How easy or difficult is it to move between menus and screens? And are those menus and screens set up logically?
- Battery type--What kind of batteries does it take, and do they match your other gadgets? (I prefer a GPS that takes AA batteries, because that's what my headlamp and flashlights take. That way, I don't have to carry multiple types for spares, and the batteries are interchangeable if necessary.)
- Mapping capabilities--Does the GPS take topo maps? Does it have computer download and upload capabilities? How much memory does it have, and is it enough?
You may also want to purchase a case and a strap to attach the unit to a belt or backpack.
A Basic But Good GPS - The Garmin eTrex series, beginning with the "10"
To me, the most important functions of a GPS for the average user are the abilities to set waypoints and do "go-to's" as well as to determine one's location at any given moment and plot that location on a map. And the Garmin eTrex 10 will certainly do that and more. This model is a dependable, easy-to-use unit, which now offers better accuracy in heavy cover and