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I bought my E-trex via e-bay a few months ago. I'm not a serious walker, but do enjoy the outdoors and like the odd mountain bike trek. I was looking for a unit that would be simple to use, but had enough features to grow with me if my needs increased. With the e-trek vista I found my requirements. Another plus is that it is possible to use it in the car quite well. The dedicated car units are too big and not practical for hand held use, but the vista covers both hand held and in car use pretty well. It's a little small on the display side for true car navigation, but if you have a passenger, then it's not a problem as they can read the screen leaving your eyes to concentrate on the road. I found that using it in conjunction with a map is the best way to navigate. Because of the small screen, it can get overloaded with detail (you need to find a compromise between two much, and not enough detail), and if you zoom in too much, you've travelled off the screen by the time it updates. However, I found that using the GPS to give you your position, and a map to know where you want to be works fine. Let's face it, it was never designed for in car use really so with this in mind, it does a good job (at a lot less pound notes than dedicated in car systems). I would certainly advise use of an in car charger (from the cigarette socket) to save your batteries. When walking / biking, it is very handy - you can just set off, and let the unit lay a track down to chart your progress so you know exactly where you've been. To get back to the same point you set off from, simply turn and trace your route back - the unit will plot your current position, and if you match that up to the route you've laid down then you're following your exact steps back home. You can navigate by the on screen map, or by using the in built electronic compass bearings. When used with the mapsource software and a
PC, you can download selected areas to give you street level mapping - right down to individual house numbers. The accuracy is very good. However, as the software is CD based, and there is no update facility, it's a picture of a moment in time, so you might find some of the businesses (shops / restraints etc) are no longer there. Mapsource CD's retail for approx. £100 - I have western Europe & the States. I've used both on recent holidays and found them very useful (Although check e-bay - you can pick up for much less than retail) The garmin unit provides accuracy down to a few feet in ideal conditions. It's waterproof (and can survive immersion in up to 1 metre of water for 30 minutes). - I've used mine for skiing and even with gloves on, operation is easy. There's only a total of 6 large buttons to press, and all functions are controlled with these buttons. It does struggle to get a signal sometimes where there is dense tree cover, so if walking thru the forest, you can't rely only on the vista and you'll need another form of navigation. (Obviously it doesn't work indoors or under buildings - tunnels, underground car parks etc - as it needs a clear view of the sky to get a signal) Battery life is from 2 x AA batteries, but it can go thru batteries at a fair rate so it's handy to always carry at least 1 spare set (maybe more if you are on a long trail) - using the electronic compass eats up batteries. There are lots of very advanced features available - I only use a small part of what is available. But the unit is capable of giving you a bewildering choice of options. The instruction manual covers all functions in an easy format, supported by screen shots - although it does assume you have knowledge of the advanced functions, and doesn't go into too much detail to explain these. - Although I guess if you need to use these sort of functions, you'll already know what they ar
e / how they operate. Connection to the PC is via 9 pin serial cable, so data transfer is not the quickest. Although memory space in the unit seems pretty good and is able to accept large areas that you choose to select from the maps on your PC. Remember that the unit relies on GPS - these satellites are actually U.S military hardware made available to the general public free of charge. I've heard reports that in times of heavy military operations (e.g recent Gulf / Iraq conflicts) the satellites go off line for public use as they become just for military use. So, as with any electronic device, it's always best to have a backup (Map / compass) in case of malfunction / loss of power etc All in all though, it's a very capable unit and meets (indeed exceeds) most of my demands. It's loaded with features, so your needs should never outgrow it. And it's got a nice robust case so can take a bit of rough handling - all this from something the size of a mobile phone that sits in your hand. Pretty impressive stuff really.
Sattelite navigation? In the palm of your hand? Surely not! Only two years ago your scepticism would have been justified, but technology has advanced rapidly during that time and it is now possible to get a range of GPS devices at a much more reasonable price. This particluar op is (obviously) on the Garmin eTrex hand-held GPS receiver, the cheapest in the eTrex family, a device aimed at the active outdoors type of a person. But first things first... what is GPS? It stands for Global Positioning System and at it's simplest can be thought of as an array of satellites circling the earth, each sending out a time signal. GPS receivers pick up these signals and, from the difference between the times in the signal from different satellites, works out where on earth you are (literally). GPS is surpsiingly accurate, down to about 20 feet on a good day, with the degree of accuracy depnding on how many satellites the receiver can pick up a signal from. It's worth pointing out that the satellite signals are not particularly strong so receivers only work when they have a clear view of the sky and definitely not inside buildings. It is capable of measuring not only your lattitude and longitude but your altitude as well. Combine this with the ability to take snapshots of your location while you are travelling and you have a device that is capable of tracking your route in 3 dimensions as you travel. The basics of GPS covered, what good is a hand-held receiver like the Garmin eTrex? Now is probably as good a time as any to give a brief description of the unit. It's about the size of a mobile phone, measuring 11cm x 5xm x 3cm. It doesn't weigh much more either. The body is made of a tough yellow plastic and it takes 2 AA batteries which provide for about 20 hours of use. The front of the eTrex is dominated by the large LCD screen, (3cm X 5.5cm), which occupies the bottom two thirds. The top third of the front displays the eTrex lo
go and covers the GPS antenna which needs to have a clear view of the sky. The sides of the unit contain all the controls, sheathed in a waterproof rubber casing. The two buttons on the right hand side are the power/backlight button and the 'page-select' button. The function of the first is obvious, the second cycles through the various displays available. The left hand side sports 3 buttons, again sheathed in rubber to protect from the elements. The top two are 'up' and 'down' buttons, used to navigate around the eTrex interface. The third is a select button, used to choose the currently highlighted option. The positions of the button make it easy to use the device single-handed which comes in useful when you're trying to stop your hat being blown off with the other hand! On the back of the unit is the battery cover, a rubberised, waterproof affair much in keeping with the rest of the unit. Finally there is the PC interface, again concealed beneath a waterproof rubber cover. It is through this port that, using the PC interface cable (sold seperately) that you can upload and download routes to/from the GPS unit. As far as the screens on the GPS are concerned, the first you see when you switch it on is a map of the sky, showing you which satellites the unit expects to be able to receive a signal from. Underneath this is a bar chart which lists all of the available satellites and the strength of the signal from each. Once the unit has confirmed it's coordinates and locked on to a strong signal from at least 4 satellites, it's ready to go. Pressing the page-select button takes you to the next screen, the map screen. This page will display a map of your route so far , indicating where you have been and the direction in which you are heading. This map can be zoomed in and out to give more or less details. *** It's worth noting that this map ONLY shows the route you have actually travelled (along with any waypoints
or features that you marked on it yourself). It does NOT give you any other detail and it is definitely NOT a substitute for a decent map and a compass. *** The next screen on the list is the Compass screen, where you get a large digital representation of a compas, showing you which way you are most recently headed. *** It's important to note that the digital compass only shows you your LAST heading. It will NOT update itself if you stand in one place and spin round as the GPS receiver only works on differences in coordinates. *** At the bottom of the screen you can also cycles through various statistics relating to your current trip using the up/down buttons. This includes things such as your current, average and maximum speed, current altitude and total distance travelled. Last on the list is the menu page. From here you are shown the time and date along with a battery indicator. It also provides you with a list of sub-menus which are chosen using the up/down and select buttons. The first of these sub-menus is the Mark menu which allows you to enter your current coordinates as a waypoint. It lets you set the name (up to 6 characters) and choose an icon from a pre-defined list. Once you are happy with the name and icon, you accept the waypoint and it is added to a list and will appear on the Map screen. The next sub-menu allows you to manage all of your waypoints, either choosing one to head for or deleting individual points (or the whole lot if you want to start from scratch). After the waypoint menu comes the Route menu, which allows you to make up routes using stored waypoints. To build a route you simply add waypoints to it. You can then choose to follow a route. After Routes comes the Tracks menu which gives you access to the track log which is essentiall a list of coordinate snapshots taken while the unit was switched on. Tracks can be saved into the units memory and once there, you can make use of the handy 'track-back' feature
which will help you retrace your steps. Finally you get to the setup menu which allows you to set things like the time format, time zone, display contrast and backlight timer, the units in which things are measured and map datums. As you can see, you get quite a sophisticated piece of kit for your money, all well packaged in a sturdy impact and waterproof case. From it's appearance it's obviously aimed at people who spend a bit of time out and about. I use it when I'm out on hiking or biking. Set a waypoint where you parked the car and at strategic points along the way add some more (usually where there's a landmark or something similar) and should the worst happen you can use it to find your way back. This came in particularly useful on a recent trip to the Lake District when the cloud descended very suddenly leaving me with no visible landmarks and precious little hope of finding my way off the moors I was on. Fortunately, as I had used the GPS to track my way up the moors I was able to use the trackback eature to guide me back along the path I had taken and down to below cloud level without incident. As a test I even used it to take me back to the car and it was dead on. Suffice to say I was suitably chuffed. *** Another safety pointer at this stage, a GPS should NOT be used as a substitute for a proper map and compass. It should always be used alongside these tools to aid and improve your situation, never on it's own. There are situations when GPS is all you have to go by, such as when the cloud descends and you have nothing to take a bearing from in which case it can be extremely handy, but remember that they are only accurate to within 20 feet at best so don't rely on them completely if you're anywhere near any big drops or other hazards.*** Being able to find out where you have been is one thing, but the other beauty of GPS is the ability to give it pre-defined routes and let it tell you where you need
to go. As GPS becomes more widespread, businesses are starting up that provide mapping information. This ranges from digitised OS maps and software that you can use to build a road route to routes that people have recorded on their GPS and downloaded for other peoples reference. A good example of the latter is mountain bike routes. A slowly increasing number of websites are offering GPS coordinates files for routes around the country. As always you shouldn't blindly trust them, but it's a good starting point. I certainly saved some of my recorded walks in the Lake District for future reference and next time I will probably take notes along the way (along with photos etc) and post them on a website for others to use. Earlier in the op I mentioned that this is the bottom of the range unit from Garmin and so it is but in my opinion it represents the best value for money. The more expensive units (costing anywhere between £250 and £400) offer additional features such as a true digital compass and a barometric altimeter for greater accuracy. They also offer a larger memory capacity for tracing routes and storing waypoints but I have not found a single situation where I would need these features and certainly not one that would justify the additional cost. Add to this the fact that the eTrex is brightly coloured and ruggedised and the plain-old bottom-of-the-range eTrex comes out by far the best value. Accessories are available in the shape of cables to connect it to a PC, Cigarette lighter power cords and handlebar & dashboard mounts and I have found www.dabs.com to be the best place to order most of these. GPS software is slowly becoming more widely available on the 'net too. Shareware programs include GPS Utility (http://www.gpsu.co.uk) and Waypoint (http://www.tapr.org/~kh2z/Waypoint/). The best commercial program available at the moment is probably Memory Map Navigator (http://www.memory-map.com/) but at £100 for the software and £25 pe
r OS map it's pretty expensive. So to wrap up then, when you first look at it you may well think that it's just another gadget. However scratch a bit deeper and you will find that if you do a lot of walking/bike riding etc. it actually offers an exceptional amount of functionality from a package the size of a mobile phone and anything that gives you a little extra help can't be a bad thing.
The eTrex GPS unit takes the best features of a 12 parallel channel GPS receiver and put them into a six ounce package that is only four inches high and two inches wide. The result is a unit that will literally fit in the palm of your hand.