Getting Started with GPS—Equipment

Val Noronha | The Geography 80-20 collection

The basic outputs of a GPS are

GPS equipment today integrates these items with other data sources and sensors: street/topo maps, traffic updates and routing functions, heart rate and pace cadence sensors, engine RPM reports, etc. We're not going to discuss all these variants. Our interest is in reading and interpreting the basic outputs above, which are common to all devices.

You can buy dedicated GPS equipment. Or you may look at the GPS hardware you may own already: a car nav system or a smartphone. We'll cover each of these here.

1. Single-purpose GPS receivers

Genie BGT-31 displays basic outputs: time (UTC), date, heading (248°), speed (2 km/h), altitude (0 m), lat-long. There are several other report screens. BGT-31 is not WAAS enabled, so accuracy is not the best.

Limited in terms of mapping and general utility, dedicated receivers display basic outputs, hence are useful for learning first principles. The inexpensive ones at the top of the list will get you started on a low budget. Those lower down offer more, like integrated altimeters, electronic compass and even cameras, and their features start to abut against tablet- and computer-based functionality. Depending on your budget and tech savvy, lower-end options plus creativity could serve you well.

Maps on board
Egoman MG331
No Not tested
Bushnell Back Track series
Not tested USA
Genie BGT-31*
No Good
Magellan eXplorist series
Some road/topo
Garmin eTrex/Oregon series
Some road/topo

*Genie BGT-31 was $150 some years ago, probably much lower now if you can find one — seems to be off the market. It includes Bluetooth and a logger (capacity depends on user-supplied SD card).

This is just a quick sampling of options and prices, both of which change rapidly. There are hundreds of devices available.

Some things to consider when buying:

Sources: in addition to Amazon and REI, look at

2. Portable car navigation systems

Dominant brands: Garmin, Tomtom. Prices: $100+ minimalist, $200+ for better models with traffic and map updates

This is not designed as advice on acquiring a car nav system for navigation. It's about coaxing your car nav system to output raw GPS readings. Generally the point of a nav system is to insulate you from the user-unfriendly language of lat-long, presenting familiar addresses and maps instead. It tends to view the world through the mask of motorable surfaces. So to display lat-long in a wilderness area, you'll need a Tools menu. On a Garmin go to Tools | Where am I?

The issue of traffic updates just begs a couple of comments. Live traffic information is broadcast to these devices over a radio channel that's entirely separate from the satellite-based GPS signal. These secondary broadcasts to the device are of varying quality. One problem is that they're 15 minutes old or more by the time they reach the device, so when congestion is changing rapidly in the first and last stages of rush hour, the device is not getting the best data. At the beginning of rush hour, the ETAs tend to be optimistic, and at the end of rush hour, they're pessimistic. Secondly, congestion/speed sensors tend to operate on freeways, not on service roads. You'll often find drivers exiting a congested freeway on the advice of their GPS navigators, only to find the alternate streets chock-a-block too, because the broadcasters don't have the data showing those roads turning into less viable choices.

3. Smartphones

A cellular system must know roughly where you are (±100 m) in order to deliver your signals. And under U.S. law they are required to be able to locate you if you call 911. Cell phones do not rely on GPS to do this. They know which cell towers your signals are reaching, and they can work out location from that.

Practically all of today's smartphones add a GPS chip for accuracy, for routing functions and to let marketers follow you around. But because that compromises your privacy, you have the option of turning the GPS on/off.

So it takes two things to use your smartphone as a GPS receiver. (1) Get an app that queries the phone's GPS and displays the outputs. Among the better apps, in terms of breadth of options, is Handy GPS. The basic version is free, and available for both iOS and Android. (2) Turn on the GPS. In iOS there are two relevant dialogs. At Settings | Privacy | Location Services, you turn the GPS chip on/off. Turning it off protects your battery and privacy. Under the main Settings page, you can turn location on/off for each app. Denying an app access to location does not save your battery, but it does protect your privacy.

Long-term, the smartphone is the most logical platform for advancing and integrating GPS functionality. For hiking, it may fail on ruggedness and battery life.

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