Got A GPS now what?

[Fido]

I have a gps and was wondering is there any courses that you can take to teach you the right way to use them if so let me know thanks.

[LOC]

Fido, I've seen "How to use your GPS" courses listed in the Surrey Parks and Rec book before (under the General Interest catagory). For a more expensive option BCIT offers a course too http://www.bcit.ca/study/courses/surv0129 .

[Fido]

Thank you will look into that.

[Schutzen]

3skills...
I'll look into the backlite thing I do'nt know if I can turn it off but I put it on the lowest time I could at 30 secs.

Loc...
Thanx for the Ozi map info I'll check it out.

[BCKID]

I agree with the above {dont' leave your compass at home} I found mine would lose the satellite in the timber at times. You need to look for a clear spot if that happens. As for batteries I found the cheapest ones lasted twice as long as the pricey Duracell ones so try out a few to see what works best. BCKID

[zedex]

I have some more advice. When you get to your starting area and turn your gps on. Make sure you let the gps acquire all satellites.Then mark the waypoint. I mistakenly left in a haste once and didnt allow proper acquisition. When i decided to track back to the truck it was no where near the marked waypoint. Good thing i knew the area. If i didnt i would have been screwed.

[J_T]

The concept behind a GPS unit is simple. While we normally position ourselves in the field using three component x,y,z components (northsouth, eastwest and elevation) the GPS unit requires one more component. Time. receiving a signal from at least four satellites.

Your accuracy is based on the geometry (position in the sky) of the satellites. If you have a unit that can tell you what your expected accuracy is (IE, within 10 metres) this is preferable

There are two basic types of GPS units that you might bump into these days.
1) Recreational - Less than $500 (Can Tire, Walmart)
2) Mapping - Over $1000

The Garmin Product (www.Garmin.com) is absolutely the best in the recreational field. (GPS 2, 12XL) They have figured the mathematical geometry of a position fix very well. For the higher end models, Trimble (www.Trimble.com) is the best. The Mapping units allow you to interface with computer software.

For the money the best units are the Garmin ETrex series. There is a new Rhino series that is a combination radio GPS unit, that will let your buddy set a waypoint, based on your position (which is different than his) and navigate to your position using the radio and GPS combo. Waypoint, waycool.

The concept that to learn about it, just turn it on is absolutely correct. You can train a monkey to use a GPS. Just turn it on.

IF you are using a recreational GPS unit remember, the OMS (original manufactures specifications) indicates the unit is a 100 metre unit. 80% of the time the unit will give you a reading that is within 100 metres of the actual position. We know the units perform better than that (most of the time they are sub 20 metre), however, you should alway keep in mind the 100 metre expectancy.

If you are using the unit with a map, in order to have a good match, you need to know what datum your map is on. In BC, the green 1:50,000 topo maps use a NAD 27 datum reference and you have to go into the setup and set your readout to NAD 27. If you are using the white 1:20,000 TRIM based maps these operate on a NAD 83 or WGS 84. The differenc in a NAD 27 coordinate position and a NAD 83 position (same position, different reading) can be as much as 200 metres by 100 metres out.

All GPS units read in WGS 84. You will also have to decide if you want UTM (metres north of the equator and metres east or west of the central meridian) or degrees of latitude and longitude for a read out. Likely UTM.

If you are using a map, when you get to general location, find a known feature on the map, take a reading, and confirm the reading to the map. Any error will likely be your error over the next 6 hours. So if the unit is South and West by 100 metres of your known point, then make a similar adjustment through the day.

To get the best readings, don't take readings near your vehicle, powerlines, concrete structures. The satellite signal bounces off of these in what we call multipath and it distorts your signal.

Why the error when we take the readings? Initially it was the military that used the GPS. As civilians started using them, they introduced what is known as "selective availability" creating an error in the signal. As I said, the fourth component in a position is time and the military adjust the time, to distort your reading.

Remember, if there is political unrest, or a war going on, you may experience less accuracy because the US military move the satellites to the hot spots. By and large the civilian consumers in the states are taking over GPS and those of us close to the 49th parallel, will see more accuracy in the coming years. If you are moose hunting in the Prince George area, remember the best readings are taken in th early morning and late afternoon.

Sorry for the length.

JT

[Rob]

Ive also got a magellan sporttrac, its a couple years older, ive also found the backlight burns up the battery but youll only need that at night so i hardly use it(the light). Ive got mine on UTM which i find makes map reading a whole lot simpler. Go to a map store & p/u a map of some area close by your home talk to the guy at the store about maybe he can give some last minute advice, you can also p/u a roamer which will break down your grids even smaller. Gps's are fun but i also always bring my compass anyway. PS i read the manuel they give with it,it didnt make a lot of sense to me so i learned what i know from talking with people & going out to play with it.

[gpoole]

If you are like most of us you won't use most of the bells and whistles. I just use mine to tell me the UTM coordinates so I know where I am on a topo map. I don't use the compass features, distance to marked point, speed of travel or any other fancy features. This way I turn it on to find where I am then turn it off quickly. The batteries last longer like this too. And you still had best have topo maps and a compass.

[Ronforca]

I have used a gps for several years.I tend to wander a long way from camp so when I knock down an animal I then mark the animal and head back to camp for help,The gps will take you right back to your animal.No more stringing surveyers tape and wandering around looking for an animal with darkness coming on.
Good luck Ron