What is Sat nav?
The Global Positioning System (GPS) is really a satellite-based navigation system (hence they're in addition referred to as SAT NAV) made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense. GPS was initially created for armed service applications, but in the 1980s, the government made the system available for civilian use. GPS operates during any weather situations, anyplace in the world, 24 hrs per day. There are no subscription fees or setup expenses to use GPS.
How it works
Sat nav satellites circle the globe twice daily inside a very accurate orbit and transmit signal information to earth. Sat nav receivers acquire this information and use triangulation to calculate the user's exact situation. Essentially, the GPS receiver compares the time a signal was transmitted by a satellite with the time it had been acquired. The time difference tells the Sat nav receiver how far away the satellite is. Now, with distance measurements from a few further satellites, the receiver may determine the user's place and indicate it in the unit's electronic map.
Today's Sat nav receivers are incredibly exact, thanks to their parallel multi-channel construction. When first turned on they lock onto satellites and so they maintain effective locks, even in dense foliage or urban settings with tall buildings.
Using GPS or SAT NAV for Walking
Whether or not you are out for a leisurely trek or a high energy walk in rough terrain realizing exactly where you are at all times is particularly valuable, specifically bearing in mind how easily the weather may alter. For trekking you basically have to have a device that employs Ordnance survey maps as these are very helpful when exploring a spot on foot or following a predetermined path – an excellent Gps will let you know even when you happen to be just a couple of feet off the footpath. This really is incredibly appealing since you can see immediately where you happen to be and also the particulars on the screen are precisely precisely the same as a paper map. For this reason a dedicated outdoors Sat nav device is an attractive choice for most walkers not least because of their robustness and ease of use.
PDAs and Smartphones are in all probability the cheapest way to obtain Ordnance Survey mapping on to a GPS, unfortunately, the downside is the fact that they are really not as rugged as a dedicated device for walkers. The brightness of the display may very well be an issue with cell phones particularly on a sunny day. Dedicated Sat Navs are usually not cheap and really the only one available on the market dedicated to walkers is the SatMap. The quality and usefulness of these units is increasing all the time. We, therefore, recommend the SatMap Active 10, a gps for walkers that we right here at My Outdoor Store, use extensively ourselves.
Wanting to Find a GPS for Walking.
Bruno is a freelance writer with a keen interest in all sorts of outdoor activities. He is co-owner of www.myoutdoorstore.co.uk - a price comparison site for outdoor clothing, equipment and activities