Details and First Impression

Garmin GPS III PLUS Details and initial impression

This is one cool gizmo. I bought it one Saturday afternoon and had it out of its box while I was still driving down the road. I was obliged to park to put the batteries in, which is to say, I was compelled to read the instruction book to figure out how to get the batteries in. I was less than a mile from home, but it had already initilized, gained satellite lock and was tracking by the time I was home. ( By the way, the lanyard clip is the battery release -- open the metal ring, rotate it a quarter turn counterclockwise and the battery compartment opens).

< Click the photo to open a page of photographs showing this unit in hand and on dashboard.

Shape and Feel: It has a versatile, detailed display window and fits snugly in your hand. It is triangular in cross section which feels odd, but it perches at a comfortable angle when placed on the dashboard of your car, unless you are on a bouncy road (I often am) in which case you will wish to clamp it firmly. It is fairly heavy, especially with alkaline batteries, and creates a sense of a well built instrument.

It can display in portrait or landscape mode, depending on whether you intend to lay it on its side or hold it in your hand with the antenna end away from you.

Operate in Dark: The Magellan is easier to operate in the dark, in my opinion, but the Garmin's display and buttons are illuminated -- making the buttons easier to find on the Garmin, hence, also easy to operate. The on/off/illumination button is shaped differently (recessed) so you can illuminate it even though you cannot see the illumination button until you illuminate it!

Endurance: It is said to run for 16 hours, 32 in power-saving mode. I haven't worn out a set of batteries yet; I am on my second set of batteries and I have had it for a couple of months. The 12 volt cigarette adaptor for the Garmin II works just fine; this unit is rated to take anything from 10 volts all the way to 32 (one source says 6 to 40), so that means it will run on 12 volt automotive power or 24 volt aircraft power. It is smart; the illuminator turns off automatically at user-changeable interval, but when it is plugged into external power, the illuminator stays on continuously (if the illuminator is turned on, of course).

Antenna: It has a swivel rod antenna that will be more sensitive to satellites down near the horizon and less sensitive to satellites directly overhead, as compared to flat antennas which are more sensitive to overhead satellites. I did not particularly like the rod antenna, but I have discovered that it is ideal when the GPS is stuffed into a fanny pack pocket and it still has a 360 degree view of the satellites. When a patch antenna (flat, as in some Garmin and Magellan GPS) is stuffed into a pocket, it can only see the satellites in front of the unit; or half the sky. Obviously, the patch antenna could be kept flat to the sky, but that means you cannot put such a GPS in a pocket. The Garmin GPS III+ rod antenna is also removeable and external antennas can be attached, which means you can put the GPS pretty much anywhere you want and still have good sky coverage.

Initialization is a snap. If you've never had a GPS before, read this. The GPS, when first turned on new out of the box, has no clue where it is, thus, it doesn't know what satellites to expect. It can take a LONG time (an hour or so) for it to decide which satellites it is even listening to, if you do not help it. On Magellan, you type in your guesstimate date/time and lat/long, and if you are within 500 miles or so, it will acquire in a couple of minutes. The Garmin gives you a world map, and you scroll to your neighborhood, click "enter" and it locks on the satellite in about two minutes. After that, it locks on the satellite in mere seconds (as does the newer Magellan units).

MapSource™ CD-ROM: You can purchase a CD that, when used with a computer, permits you to upload highly detailed maps into the GPS III+. First Impression: Not very impressive, it did not seem to contain any of the dirt roads that I was interested in exploring. Unbeknownst to me at the time, most of the detail does not "turn on" until you zoom real close (less than 0.3 miles indicated). This can be changed using the "map detail" menu item on your map setup screen. In the city, too much detail makes the screen go black, but in rural areas, you will probably want to turn on maximum detail so you don't miss an important road that just happens to have been marked as "tiny" and hence not visible except at maximum zoom or maximum detail setting. Once I figured this out (by accident), the dirt roads north of Canyonlands National Park are accurately and comprehensively mapped. It made finding my desired destination easy, even in the dark.

The MapSource™ CD appears to have excellent detail and accuracy, but is no competition for DeLorme's Street Atlas™ for general utility. It is wise to have both; the MapSource for uploading to the GPS, and the StreetAtlas for plotting a destination and obtaining the waypoints. The DOS-based program for waypoint uploading and downloading is expensive and does not appear to have much utility.

Map Storage Capacity: It was tough to find, but the Garmin GPS III+ holds 1.44 megabytes of MapSource information, so you can select maps until you hit the limit. It is quite a lot; I loaded 5 counties into 1.1 megabytes. This is revealed in the map setup screen where you can turn off the MapSource information, it reveals how much storage space you have used. Why turn off MapSource info? Each MapSource map is approximately one county, and is rectangular -- however, the data inside the rectangle often does not go to the edges of the rectangle. That means, and you may be surprised by it just as I was, as you drive to the edge of the county that you uploaded, suddenly your map screen is full of cross-hatching -- no roads, boundaries or anything but your little black triangle and "breadcrumb" trail behind it. As soon as you enter the next county, the basemap becomes visible and all is well. This "no map zone" can be rather large at times, however; several miles or more. Zooming out will restore the basemap, and turning off MapSource info will fix it, and so will loading the adjacent county into the GPS (if it will fit, of course).

The moving map is the most conspicuous feature. It can zoom out to cover the entire world although highway information is loaded only for the USA, North and South America (less detail in South America and less detail north of Edmonton, Alberta; or Saskatoon, Saskatchewan) . It can zoom in to a scale where approximately 1 centimeter is shown as 120 feet. At that scale, driving around in a parking lot shows up on the track plot. Then you can zoom out in 22 steps to 500 miles per centimeter. Garmin's website offers details about what is included in the basemap.

Compass: It has a full circle compass of large size and excellent detail, which gobbles up the screen. It's pretty, but not always needed. You can choose a smaller compass but much larger numbers revealing speed and distance to the next waypoint.

"Road" Route Display: The Garmin "road" display is an oblique view in the direction of travel, and the track is a black line. I found use for it on the bouncing dirt roads of Utah's canyon lands where you need something big and bold, but also, anticipates which way you are going to turn.

The route screen offers a bonus; a table of waypoints and distances on each leg; plus a sum total of all legs. You can also perform fuel computations for the trip.

Multiple Data Screen: A general purpose data screen exists on the Garmin; it has an edge-reading compass at the top, six user-configurable windows, and the latitude, longitude, date and time in small print. This appears to be the only place that the actual latitude and longitude appears, and in this regard, the Magellan appears much superior.

Also, the Magellan remembers and displays its most recent fix (lat/long) whereas the Garmin does not if it is not currently tracking satellites. If you go indoors, the Magellan can still display its last lat/long but you just get dashes (---) from the Garmin. The data fields are: Altitude, Avg Speed, Battery Timer, Max Speed, Odometer, Speed, Sunrise, Sunset, Track (the compass direction of travel), Trip Odometer, Trip timer, User timer, and Voltage (for the battery -- by the way, when you are plugged into the cigarette lighter socket, it reads your automobile battery voltage -- very handy for alternator and battery quality checks). It lacks the moon phase of the Magellan which is convenient for camping and fishing projections. Also, the Magellan GPS 2000 XL allows one to compute sunrise, sunset for any latitude/longitude and date, for looking elsewhere and into the future. If the Garmin can do this, I have not yet discovered how. After all, my interest may well be to compute moon phase and sunset at Lake Powell, 300 miles away.

So, if the purpose is to include the GPS in a photograph to establish the location, date and time; the Magellan's huge latitude/longitude (or UTM coordinates) display is superior -- it is exactly what you need to establish where and when in 3-dimensional space. But for an impressive display of a lot of info, the Garmin is hard to beat.

Suggestions for Garmin:

display more map in the direction of travel, less map behind. In other words, don't center the bug. It may be that this is yet another operator configurable feature (it has many deeply hidden features).
Let the computer decide to show some "small" roads at larger scales when no neighbor roads exist. For instance, the road that goes out to Horse Thief Point is a dirt road, and shows up only on very close zoom, but in fact, it has a meaningful destination -- an airstrip and boat launching ramp down on Green River, and it has no competition, thus, it should be visible on wider area zooms.
MapSource™ CD can use a LOT of features. The most important feature I would give it, would be the ability to designate certain roads as "preferred" which appear at any zoom level and which perhaps optionally are highlighted in some manner. Setting waypoints on the MapSource computer display would also be very useful.
Edge boundary problems need to be fixed. Imagine my surprise when, after loading the Cache County map, I was driving down to Salt Lake City, and right at the edge of Cache County, the map ceased, and became a crosshatch grid, through which not even the basemap was visible.
Other features: I like the altitude recording of Magellan waypoints. This is missing from the Garmin unit. By not having so much information, it may be that is how Garmin can store so many waypoints, but the value of each waypoint is slightly less.
The latitude and longitude last fixed should remain visible or at least recallable. The Magellan has an "unlock" indicator to show that thedisplayed fix is not current, but if all one has done is take the GPS indoors, then it is certainly a good, and perhaps useful fix nonetheless. The Garmin blanks out the lat/long when the signal lock is lost but otherwise does not let you know that you have lost satellite lock. So, unless you think to mark a waypoint before walking indoors, you lose your lat/long. I prefer a lock indicator and the most recent fix should be "persistent."
A "Here You Are" datascreen, large numbers showing coordinates, altitude, date and time; suitable for inclusion in a photograph.
The voltage screen is potentially very useful; but at what voltage does the unit cease to operate? Is 5.32 volts a good thing, or should I change batteries? Eventually I will hook it up to a variable power supply and find out (and report on this web page, although I suspect different units may have different cutoff points).
The moon phase thing may seem trivial, but I actually used my Magellan GPS to choose a camping date that would have plenty of moonlight, for a moonlight swim on Lake Powell. The Magellan also can project sunrise/sunset and moonphase for arbitrary locations and dates (such as for a distant camping trip). Still, I would not sacrifice the right-now, right-here, sunrise, sunset indicators on the data panel, since it is great when traveling to know when the sun is going down (and avoid driving due west at that time).

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