One of These Could Help Him Find the Right Way at Last

Call me Wrong Way Corrigan. Give me a map and compass, and I’ll find my way . . . eventually. I call it just being turned around a little. Some of my hiking companions call it something else: being lost.

Whatever you call it, it’s less likely to happen if you’re carrying a Global Positioning System receiver. These increasingly popular and affordable units pull in signals from a U.S. military satellite network to determine latitude and longitude. Put the “lat-lon” cross-hairs on your topographic map, and you will know exactly where you are.

GPS units are great for marine navigation. Off-road enthusiasts can use them to meet up at a specific location in the trackless desert. And GPS units with mapping software are standard equipment in many luxury cars.

For this review, I tested two small, hand-held GPS units: the Magellan GPS 315 (about $150) and the Garmin Etrex Summit (about $250). The manufacturers, which also make less-expensive models (see chart), specifically recommended these units for hiking.

I’ve owned a similar unit for three years and been frustrated by its inability to pick up satellite signals in steep canyons and mountainous areas. That’s not a problem with the two models I tested from the major manufacturers, Magellan Corp. of San Dimas and Garmin International of Olathe, Kan. Both were able to receive signals anywhere there was a view of the sky.

But you should consider your actual needs before shelling out $150 to $250 for these devices. They won’t replace your map and compass, and you’ll need to invest quite a few hours to learn to operate all their functions.

What They Do

Pinpointing your location is, of course, the main purpose of the GPS system. But most GPS receivers--including the ones I tested--also measure elevation, distance and speed of travel. The latter is a nifty feature for anyone who has struggled to gauge his or her stride with a mechanical pedometer.

Both units I tested come with navigational aids, including backtracking technology that enables you to create an electronic “bread crumb” trail to follow back to your campsite or starting point. Both also connect to computers, enabling users to download software upgrades and maps of landmarks for specific regions.

Of the two, I found the Etrex Summit easier to use and operate. It costs more but has two special features: an electronic compass and an altimeter that can be calibrated by barometric pressure, for a more accurate reading than GPS-calibrated elevation.

Ease of Use

My test models arrived the day before I left on a weekend backpacking trip. I had little time to study the manuals, and was unable to make full use of either unit right out of the box. But right away, I was annoyed that neither one had a clip to attach to my belt or the pack’s sternum strap. As a result, I couldn’t check the odometer and elevation readings as we hiked. So they rode in the pack, dead weight.

Later, I set aside a Saturday afternoon to study both manuals. Here is where the Etrex Summit was hands down the winner. It came with a detailed manual that clearly explained each feature.

Navigation

Using the latitude-longitude, elevation and odometer functions on both units was easy. But learning the navigation features took some time.

Both GPS units allow you to create “way points” that are stored in the receiver’s memory. Mark a way point as you set out on a hike or along the way, and the GPS will help guide you back to it. Each receiver can also draw a line--something like the track on an Etch-a-Sketch--so you can retrace your route.

These features are most useful for boaters and people hiking in areas with no trails or at night. But they are not easy to learn how to use.

The Garmin manual includes a test run that allows you to take the unit outside and walks you through each step. But the Magellan manual’s explanation of its navigational functions was confusing.

To “Edit a way point,” for example, the manual instructs you to hit Menu from any NAV (navigational) screen and select way points. I tried doing that from every NAV screen, and never saw a way points entry to select.

It was fairly easy to figure out the electronic bread crumb trail on the Garmin machine; on the Magellan, repeated attempts to display this function ended instead with me getting a series of alpha-numeric codes.

Unfortunately, the Magellan manual seems to take pride in its minimalist approach. “In order to get you outdoors quickly,” the introduction says, “the manual is designed with key sequences rather than wordy sentences.” Fortunately, instructional videos (for various GPS models) are available for about $20.

Field Test

After reading both manuals, I took the receivers on two hikes in Deukmejian Wilderness Park in Glendale, where trail distances and elevations are clearly marked on park maps at the trail head.

Until recently, the accuracy of civilian GPS receivers was intentionally distorted (as an anti-terrorism measure) but President Clinton signed an order May 1 ending the practice, and dramatically increasing the accuracy of the units. How accurate? We were about to find out.

As I hiked, I noted that both units measured distance accurately and gave identical “lat-lon” readings. But there were significant discrepancies in their elevation readings.

The main trail head at Deukmejian Park has a posted elevation of 2,335 feet. On my first trip, the Magellan showed an elevation of 2,358 feet. But the Etrex Summit was way off, showing 2,204 feet.

Half a mile up the hill, I stopped to check the elevation at a lookout marked on the map at 2,660 feet. The Magellan was dead-on with a reading of 2,660, while the Etrex Summit registered 2,519.

Puzzled, I called the manufacturer. The Etrex Summit, it turns out, has two ways to calibrate elevation. The preferred method is an altimeter set by barometric pressure. But the only way to calibrate it is if you know the current pressure, or the correct elevation.

There is an auto-calibration function on the Etrex Summit to make the GPS elevation reading more accurate. But this feature is not mentioned in the main section of the manual, only in an appendix. And the function is found not on the unit’s calibration screen, but instead on a separate setup screen.

After setting the auto-calibration, I took both units back to Deukmejian Park. At the 2,335-foot trail head, the Etrex showed 2,368 feet--off by just 33 feet now--and the Magellan read 2,336. At the 2,660-foot lookout, the Etrex read 2,672 and the Magellan read 2,669.

At a second lookout, with a posted elevation of 2,715 feet, the Etrex read 2,739 and the Magellan read 2,731.

In each case, the Magellan was closer to the posted altitude.

The Garmin folks note that the barometric pressure altimeter is more accurate than GPS-calibrated elevation. But having to know the base elevation or barometric pressure takes away some of its advantage.

Backtracking

The navigational features were mixed; I was able to figure out the electronic bread crumb trail with the Etrex receiver, and it appeared to track my twists and turns correctly. But I could never get the Magellan to perform this function. This was undoubtedly a case of operator error, but a clearer manual would have helped.

The Magellan did have one feature that was nice--a built-in database of lat-lon coordinates for major cities. I entered in the coordinates for Burbank, and sure enough, the receiver pointed in the right direction.

At each stop, I also checked compass headings. The Etrex always had north where it was supposed to be, but north on the Magellan unit was just as likely to be east, south or west.

The manual was no help, so I called the company’s toll-free consumer hotline. After a few minutes on hold, I was prompted to record a message and await a return call. A few hours later the call came and I learned that the Magellan doesn’t have an electronic compass like the Etrex Summit--meaning you have to actually be moving so the satellites can show your direction. I think most hikers stop when they take a compass reading. With the Magellan, you won’t have that luxury.

For good measure, I called the Garmin hotline as well. I waited 30 minutes on hold before giving up. Both companies post answers to frequently asked questions on their Web sites (https://www.garmin.com and https://www.magellangps.com) and allow you to e-mail specific questions if you can’t find the answer.

The Bottom Line

Backpackers love gadgets, and a GPS is fun for show-and-tell around the campfire. Whether it’s $150 to $250 worth of fun depends on your needs and budget. Most recreational hikers probably won’t need the navigational aids engineered into these things. For my money, a simple GPS receiver that offers lat-lon, odometer, and elevation for about $50 would be attractive.

If you do buy a GPS, you should still pack your compass. It never needs batteries--and it’s easy to use.

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To read past E-review columns, go to https://www.latimes.com/business/columns/ereview.

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GPS Navigation Devices

For this review, two hand-held units were tested: the Garmin Etrex Summit (about $250) and the Magellan GPS 315 (about $150). The manufacturers also offer other models:

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GPS model Weight Battery life Miscellaneous Garmin Etrex 5.3 oz 22 hours Bright yellow case $120 Garmin Etrex 5.3 oz 16 hours Barometric $250 Summit* altimeter, elec- tronic compass Magellan 7oz. 24 hours Basic unit, fewer $100 GPS Blazer navigational features Magellan 7 oz. 20 hours Built-in database GPS 315* of world cities $150

Price Garmin Etrex Garmin Etrex Summit* Magellan GPS Blazer Magellan GPS 315*

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*Tested model