GPS Basics

First, some basic GPS history

The Global Positioning System was invented by the U.S. Department of Defense and Ivan Gelling using eighteen satellites together with their ground stations primarily as a navigational tool to calculate geographical locations. The satellites are geostationary, or geosynchronous, meaning that they revolve at the same rate as the earth rotates, so they always stay above the same place on the earth’s surface.

Two major brand-names of handheld GPS units

There are many brands, but the most common handhelds are:

Garmin -- 22 models, ranging in price from about $115 to $550

Magellan -- 8 models, about $110.00 to $450.00

That’s 30 of the newest and most popular compact GPS receivers to choose from! How do you make a decision?

What’s your purpose?

I talked with our local sporting goods retailer to get advice. If you use your ATV as a hunting vehicle and/or want to use your GPS unit as a fishing tool, it would probably be worth your while to consider map software capability. And there’s plenty to consider. You can get CDs for varying purposes. MapSource™ has a quite a few CDs including: Roads and Recreation maps, USA Topographical Information, Metroguide – for residential and business addresses, hotels, restaurants, emergency etc., and World Map. When I was in our local sales and service center, I noticed software for Wisconsin ATV trails. I imagine most states probably have them available. Make sure the software you purchase is compatible with your brand-name GPS unit.

As trail riders, we were most interested in using our GPS for tracking our rides and finding our way home when we got lost. We decided against purchasing additional map software because trails are added and/or changed in our area often depending on weather, wildlife, and wear and tear. This would make map software obsolete shortly after we purchased it.

A few options

Here are a few of the options available on handheld GPS models.

Most have 12 channel receivers and WAAS capability

Antenna type: patch, detachable, quad helix, or built-in quad helix.

Acquisition time, the time it takes the unit to acquire satellite information based on manufacturer literature. Garmin - 0:15 to 0:45 seconds, Magellan – 0:15 seconds to 2:00 minutes.

Navigation accuracy will vary from <15m (Garmin) to <7m (Magellan) depending on number and strength of satellites acquired.

MB of memory: 1 to 115.

Number of waypoint and route storage capability. Most store from 1to 50 routes and 50 to 250 waypoints.

Most have waypoint icon options. It’s nice to be able to plug in an icon, a gas pump icon, for example, at your favorite fill-up.

Some have a tracback mode option, but some don’t. Since our primary use was to keep us from getting lost in the woods, we opted for tracback.

Compasses. GPS computes compass headings if you are moving forward at least two MPH. Some units have an electronic compass that allows the user to read the heading while standing still.

Barometer and altimeter.

Calendar.

Battery life from ten to thirty hours. Most units can use AAs. We plug ours into to the 12 volt jack on our quads. See photo.

Display sizes vary from1.7 x 1.3 to 2.2 x 1.5.

Number of pixels varies from 128 x 64 to 288 x 160.

Display type: color or gray scale.

Alarm capability.

USB or serial capability.

Hunting/fishing calculations

Celestial calculations.

Tide information.

Unit size (HWD): 2.9 x 6.4 x 1.33 to 7.5 x 2.3 x 1.8.

Unit weight: 5.30 to 12.25 oz.

Waterproofing. Most are IPX7.

Garmin GPS 60

We chose the Garmin GPS 60 because price was an issue (approximately $180) and we weren’t interested in a lot of memory (1 MB) for software storage for maps. It stores up to 50 routes with 250 waypoints in each. It automatically puts in the date and time of a waypoint, and then assigns a number that can be changed to a name using the rocker switch. We thought the Tracback mode option on the Garmin 60 was important for our uses. The display size is 2.2 x 1.5 with 240 x 160 pixels in a gray scale display. Unit size is 6.2 x 2.7 x 1.4., 5.4 oz. without batteries.

GPS Mounts

There are a variety of GPS mounts made just for ATVs. They range in price, beginning at about $60. As you can see in the photo, we tuck our unit into a small pouch along with our cell phone.

GARMIN GPS 60, Basic Operation

The Garmin GPS 60 has 5 main pages or screens and indicates the level of battery charge in the upper left corner. When you turn it on, it opens to a greeting page and then automatically goes to the Satellite page.

Satellite Page: displays longitude and latitude coordinates. Includes the number of satellites providing information and the relative strength of each signal.

Information Page: heading, speed, max speed, odometer, elevations. You can program your choices and whether you want small or large print, which is nice for people (like us) who usually need reading glasses to see anything smaller than a matchbook.

Map page: Zoom out to 200 miles and in to 20 feet. You can set the unit to declutter the screen of extraneous information.

The solid triangle indicates your present location. You can depress the “quit” button to back up a page without altering any settings. You can set North at the top of your screen or Heading at the top of your screen. We like North at the top, and use Heading at the top of screen to orient ourselves to N. The Map Pointer/arrow will give latitude and longitude coordinates as you move it around the map and will also calculate mileage as the crow flies. Tracking is automatic and is shown by small black dots. Double dots appear when you are tracking back, but they are very small so you need to look closely at the screen to see whether they are single or double. You can get 2D or 3D navigation, depending on the number of satellites that are drawing information.

Compass page: shows reading with either North at top or Heading at top of unit. Gives “as the crow flies” information.

Menu page: shows 12 available icons from which to choose including: calculator, tracks, routes, date, setup, and others.

We are primarily trail riders and so are most interested in marking points on our travels, called waypoints, so we don’t get lost. Use the “mark” button at the point you want to mark. The unit will assign it a number and will tell you the date and time. You can also name your waypoints and add an icon at this point using the rocker switch and menu option.

Hypothetical example

Let’s say we’re out riding and come to a fork in the trail and it’s not marked by any signage. We stop and hit “mark” button. It shows up as #36 (for example). We use the rocker switch to enter a name. (We call this one, “fork number one”, for example.) Then we press enter to record the waypoint and continue exploring the trail. At the next fork, or point of interest, we stop and hit the “mark” button again. The unit names this one #37, we rename it “fire tower”. There’s a gas station here, so we add the gas icon and then press enter. You get the general idea.

At any time during our ride, we can push the “find” key and it will list all the waypoints we’ve entered so far.

More advanced maneuvers - Routes

A route gives straight line directions from one waypoint to another. You can create routes with multiple waypoints by using the Route icon on the menu page. You can also edit routes by adding or removing a waypoint, changing the order of the waypoints, or by replacing one point in a route with another.

GPS units can be complex and sophisticated. But remember, whatever unit you choose you don’t need to be an expert on every facet of operation in order to get out there and find your way around. Happy trails!