GPS is wacky

path1 wrote:
Call Garmin. Be specific with what is wrong, they might have answer.

Got one last month and sales guy told us about going to a Garmin seminar and was telling us about some of the strange problems they run across. Worth a phone call.



Ours was made in China, it only speaks Chinese... OK joking!!! Just had to throw that in. Ours works fine.:)

I've had GPS direct me via different routes, coming and going, in bothe USA and Canada. Had nothing to do with which country I was in.

Call Garmin. Be specific with what is wrong, they might have answer.

Got one last month and sales guy told us about going to a Garmin seminar and was telling us about some of the strange problems they run across. Worth a phone call.



Ours was made in China, it only speaks Chinese... OK joking!!! Just had to throw that in. Ours works fine.:)

There are multiple parts to the system. One part is the satellites that orbit the earth and broadcast to the GPS receivers on the ground, on the water, in the air, etc.

Another part is the calculations that take place in GPS unit to determine a lat/long/elevation for the unit.

A third is the datum used by the GPS system (WGS84) which provides a mathematical model of the earth's surface.

Also, there are the maps which are used to display the location of the GPS unit, nearby roads, rivers, waterfalls, Walmarts, etc. etc. to the user.

Local maps in "backwoods" areas tend to be less precise, and are often older and were produced on older and local datums which don't match WGS84 (which means that a given lat/long location (say of a bridge) as measured by the GPS could be miles away from the place the bridge shows up on the non-WGS94 map.

More money and effort is spent making the maps used in the GPS in your hand or your car or RV to be accurate in busy/important areas - while out in the boondocks they may have just picked up some out of date and inaccurate map because they don't want to spend the time and money it takes to make and keep maps up to date for areas which are seldom travelled.

Note that the maps used in different GPS units may have been made by different map making companies and so may not show the same position on the MAP even though they calculate the same lat/long.

There are more factors (like the use of local datums in map making) that can affect the accuracy of your GPS - such as a large volcano eruption which changes the earth's center of gravity :).

Complete ignorant BS

It's the -same- satellites.

I bought my most recent Garmin in the US, and brought it home to Canada. Never any problem.
What model is your Garmin?

We are having the same problem. The GPS goes insane in both Canada and Alaska. We took a picture of our GPS screen when we were near Fairbanks and it actually said "Go Thata Way." Good reason not to depend solely on the GPS.

Could you tell us the general location where the GPS acted abnormally?