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Re: [RC] [RC] GPS - April

Hi, Dave,

It actually depends on a lot of things. The answers to the following questions can go a long way towards answering the original question.

How good was your GPS signal? Where did you carry the GPS? You'd have to have a good solid lock on as many satellites as possible. I suspect the Tevis trail is probably one of the more challenging in respect to GPS technology. The Legend units do not have the high sensitivity SIRF III receiver that many of Garmin's later units have. So that right there can be a challenge to the accuracy of the unit in the Tevis environment.

Was the 6.1 mileage readout come directly from the unit itself or did you load up the track point data onto the computer and have a program calculate the distance from the track points?

What setting were you using for recording track point data?

Was WAAS enabled or not? (not sure this would make a difference in your exact location, though)

Are you running the latest firmware for the unit? This can be downloaded from Garmin's web site and sometimes can make a difference.

The last question to ask is how and when did the Park Service come up with the 8 mile distance? Their method of measuring may have been flawed or not updated or based on old, unreliable maps. I'm not saying it is wrong, I'm just saying it could be.

Nashville, TN

On 4/24/07, Smith, Dave <dsmith@xxxxxxxxxxxx> wrote:

Just used for the first time my new Garman "Legend" and I have a question for those of you who know something about GPS.  We rode the Western States Trail (Tevis) yesterday from the Hwy.49 crossing to a mile past Poverty Bar.  The Trail signs said that distance was about eight miles one way.  The GPS, however, stated it was only 6.1 miles one way.  Why the discrepancy?  I can't believe the state parks/WSTF were that far off when posting their signs.  So what's the explanation?  Thanx.

"It doesn't matter how slowly you go - as long as you don't stop!" - Confucius
[RC] GPS, Smith, Dave