In the basic post on GPS, we explored what GPS was and urged that you consider your needs for a handheld GPS before buying one. There are many features available on the various models out there, and there may be some features you would like, and likely some you would never use.
Screens
But before we get into the more exotic features, let’s look at the basics. One of the most important and basic features of any GPS is its screen. The screens on handheld units are basically of two flavors—monochrome and full color. As you would expect, the color screens are a premium feature and add to the cost. Screen size is also a significant consideration. A small screen can be very hard to see, and even if it looks OK in a store, taking it out into bright sunlight can really change a screen’s visibility.
Unit Size
Overall size and weight of the GPS unit are also something to consider. If you are planning to carry the unit around on hikes, small is definitely better. If it is so large and heavy that it gets left behind, it does you little good. It might not seem like it, but every ounce counts when lugging it around all day. On the other hand, if you are mounting it to your bike or boat, or driving into remote areas, its overall size might be less of a limiting factor.
Data handling
Be sure to review the unit’s ability to store waypoints and routes. A waypoint is simply the coordinates of any point you would like to reference again. For example, you might want to mark your car, camp, or house as a waypoint. It is fun when you are out in the boonies to see the direction and distance back to the house (“Look, we are 454 miles from home!”). Most units allow you to store several hundred to a thousand or more points.
A route is a series of connected waypoints that moves you from a beginning point to a destination. For example, on a hike you might start at the trail head, travel to a junction with another trail, take the right fork, and end at your camp. The route on the GPS will direct you from point to point as you go.
Some GPS units will allow you to save tracks. This is like leaving digital breadcrumbs. As you travel, the unit will mark your path along the way, showing where you have been.
Some of the GPS units allow you to connect them to a computer and move information back and forth between them. This is really handy in a number of ways. You could plan your route at home on the computer, upload the route to the GPS and let it take you on your way. Or, you might like to wander off and blaze your own trail, then download the track record to your computer to save a record of where you went.
Another important information-sharing feature is being able to upload additional maps into the handheld GPS unit. Most come with pre-installed maps, but depending on the unit, its maps might be more appropriate for a day hiking the golf course than trekking through seldom-explored wilderness. You can purchase software and map sets to load into your GPS so you could have full map details of the region you are planning to visit while in the field. You can also get free maps for Garmin GPS units at GPSFileDepot.
Weather resistance
Units might be billed as water proof or water resistant. Water resistant means that the unit can handle being splashed with water. Water proof means the unit can take being fully submerged in the creek or lake. Clearly, if you are going to be out in inclement weather, water proof is going to be an important feature. However, water proof does not mean you should plan to swim with it.
Signal receiving
Units vary as to how well they can receive the signals from the satellites. More expensive models often feature better signal capabilities that allows them to provide your location through trees and other sky-coverage. If you are going to be using your unit to travel in remote regions, make sure to get a high sensitivity receiver. You can also explore getting one with Wide Area Augmentation System (WAAS). This system supplements the standard GPS satellite system and provides for increased accuracy. It is not available everywhere, but if the unit you have is capable of receiving the WAAS signals, it will at no extra cost, and will increase the accuracy of your locations up to five times.
Battery life
Finally, you might consider battery life and type. Most units run on disposable batteries, typically AA, but they do not all consume batteries at the same rate. Some units have AC adapters, and some do not. Some have an internal rechargeable battery. Each style has trade offs. For example the disposable battery option might be fine for use a few times a year, but if you are a regular adventurer, you could spend a lot of money on batteries in a season.
Those are some of the basic features to consider. In future posts we will look at some of the fancier features, and investigate specific models.