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68

There are a number of different ways to do this. Method using GPS, compass and Google Earth. Get the GPS coordinates of where you can see the tree from. Take a bearing with a compass to the tree from that location and write it down. Move to another location a decent distance away from the first where you can also see the tree. Take another bearing with a ...


26

I'd give them whatever my device or map provided me, and let them convert to whatever their devices or maps use. Anyone used to receiving lat/lon coordinates regularly should be able to convert from various formats to whatever they use internally. You're the one in trouble with limited resources. You're out there with a broken leg, lost, in the cold or ...


21

If you're not using the device to find your way, it is useless as far as the GPS functionality is concerned, no matter whether it's switched on or off. If I know they are looking for me, would they pick up the signal, if I switch it on for short periods every now and again? What signal? The GPS signal is sent by satellites, GPS devices receive this ...


17

I think you already answered your own question. Most dedicated GPS devices are more rugged, have better battery life, and don't require a data connection to work well. A phone has a lot of power overhead and is fragile. There are a few possible advantages to a phone. If you're already going to be carrying one, it reduces the total weight required. It's ...


16

Most GPS receivers in phones do not work nearly as well as stand-alone GPS devices. Usually, one wouldn't notice this because phones use assisted GPS where they get the orbital data and/or almanac of the GPS satellites as well as the exact time from the GSM network. Also, they have an approximate position of the device. Without that data, phones are very ...


14

I would recommend UTM coordinates; it avoids the formatting uncertainty of lat/long and is better suited for ground operations. (Easy to translate to paper maps, define search areas, and calculate distances.) If you use the WGS84 datum, the numerical portions are also identical with the military grid reference system (MGRS) and the national grid (USNG). ...


13

GPS systems can, and do, work everywhere you can get satellites. The coordinate system -- or datum -- you choose to use should vary (even in the US) depending on the maps you are working with, your project needs, the area you are working in, or what the legacy system you are dealing with... In the history of map-making, a ton of different projections and ...


13

Take two compass bearings from two known GPS coordinates but different azimuths. Then just use the formula to calculate their intersection. Aviation Formulary -- Great Circle Navigation Formulae -- Intersection of two radials How to compute the latitude, lat3, and longitude, lon3 of an intersection formed by the crs13 true bearing from point 1 and ...


12

Let's go through the different aspects of phone versus dedicated GPS device point by point (however, quite surely without being complete). Basically you have to decide which points apply in your situation and how you weigh them. GPS reception and accuracy When the first smartphones with GPS units hit the market, there was the saying that their GPS ...


12

From your three options, a Dedicated GPS unit is going to be your best bet. Smart Phones barely last a day. If you're out of coverage, the phone will keep searching for network and battery will die as quick as a cat fight. Of course you can use the airplane mode but we all know how long they last. GPS watches do last a long time. It will vary a bit from ...


11

GPS is simply not a good way to measure trail distance. This is because the raw GPS fixes have a lot of noise on them. If you take them literally, then you get a much longer distance than you actually moved. If you low pass filter them too much, you cut off corners and get a shorter distance. The usual algorithm is to apply some low pass filtering, but ...


10

Use the GPS to determine your position and then text or email that to your rescuers. That will be the end of the GPS's contribution to the rescue process. Staying put is generally best (saves your energy and ensures you don't move into an area they have searched and think you are not in) but that place should be safe and you should be discoverable in it. ...


10

I don't know what phone you have, but there appears to be a relatively simple Android app called "GPS Coordinates GPS Location" that claims to be able to text your coordinates without requiring a data connection. Edit: The app has over 100,000 downloads with people claiming it does exactly what it states.


10

First thing I would try is to see if I could pick the tree out on Google Earth. https://earth.google.com/web/ In many locations, especially near mid-sized or larger towns and cities, even the tree canopy is modeled in 3D. If your tree is located in such a place, it would be easy to pick out and retrieve the coordinate.


9

GPS (wikipedia) is based on orbiting satellites and so is accurate worldwide. There are other similar systems in use or under development, run by other countries (Russia, China, India, and the EU), but the US GPS still works everywhere. This stick shadow method should work the same north and south of the equator. The constellation you should look for down ...


9

Garmin GPSMap 182C and Simrad TP32 share the same language (NMEA 0183), but they do not have enough in common to talk about. The NMEA sentences that the 182C can transmit are GPRMC, GPGGA, GPGSA, GPGSV, GPGLL, GPBOD, GPRTE, GPWPL, PGRME, PGRMZ, and PSLIB. The first two letters of these identifiers are the Talker ID. GP stands for GPS receiver. PG and PS ...


8

Always have a water proof map of the area you're traveling in ( one with coordinates on each side if you can help it ), and a compass you can use to triangulate your position with. You'll be better prepared in an emergency and more confident outdoors in general if you practice triangulating your position until it comes naturally: http://www.rei.com/learn/...


8

I live in Sweden and I hike a lot in the wild. My personal top three properties to look for in a handheld GPS receiver for The Great Outdoors: Battery life Battery life Battery life I honestly don't care if the measurement is 20 metre off. In the Swedish mountains, it usually isn't, there are no deep canyons, and if there are you can only go in one ...


8

According to everything I have found on the web and experienced with my own watch, the watch will not register as mass storage so that you could access the recorded logs directly. Therefore you cannot just plug the watch to a random computer and copy he logs like it was a USB thumb drive. But, there's at least some help: Computers running on Windows or ...


8

I would consider using OSM as they are available for garmin devices.


8

I use Timble GPS Hunt Pro on my Samsung Galaxy S5 phone. You can download topo, BLM boundaries, private property and other types of maps that work just fine without a cell signal. The maps I use are incredibly detailed. If you do have cell coverage, you can add weather overlays. Map prices are reasonable, and you can buy a subscription that lets you ...


8

There are two main things that can go wrong with gps accuracy. The first is the quality of the signal, which can be less than for a dedicated gps unit (less space for an antenna and other design compromises). Of course the question of how you carry it comes into play here (a low pocket isn't very good and this may be worse than with a dedicated unit ...


7

I'd say the following are important things to have: Good signal strength is a must - Geocaching will often take you into built up areas or wooded areas, and it's incredibly frustrating going round in circles with an inaccurate GPS when one with a better signal strength could home in on it with no problem at all. Good battery life, preferably with standard ...


7

The easiest option is to use this website: Garmin.Openstreetmap.nl It has an option to select just the map tiles you want, so you can get a map for a fairly small area if you want. To do this, choose the option for "Enable manual tile selection", then click on the tiles to select them. Then enter your email address, and click the button for "Build my map". ...


7

If you really do need exceptional accuracy, you could use the solution many Ingress players use - a good Android phone with a battery pack. In the game you often need accuracy of 2 or 3 metres - so the Galaxy S3 or a phone paired with the Nexus 7 (which has an excellend GPS) are the tools of choice. The game uses google maps and wireless navigation, as well ...


7

For your situation I strongly advice against relying on your phone. It's a great backup but to much of a risk to use as a main device. Three reasons to get a dedicated gps: Batteries: A gps mostly works on standard AA batteries which can be bought anywhere and rechargeable ones are easily charged on solar energy. (look up goal-zero for instance). Rugged: ...


7

You’ve consistently maintained that you want to get the gps location of that tree, and you’ve said that the displayed view is the only one available and eliminated any method that uses a second line of view, including google earth. Since you’ve restricted yourself to the one line of view, you would have to get an accurate range, compass bearing, and ...


6

For compasses, it will depend on the model. You can get globally balanced compasses like the Suunto M3 Global, but Silva compasses (probably the most common in Europe) tend to be balanced for the Northern Hemisphere. As LBell says, they'll point the right way, but just won't work smoothly so you run the risk of taking inaccurate bearings. It's worth ...


6

I can't help you with exact configurations. But as usual this kind of thing has a basic rule. The less it's activated, the less it will use it's battery. Standby mode (time it spends counting the seconds to next use) will use almost no power at all. As soon as it comes to life it will aquire a GPS signal, Triangulate it's position and send it to a server ...


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