Question for someone who knows more than me about GPS

[olcoon & Tigger2]

I bought a Garmin Map76s in March. Until this last weekend the best accuracy I could get was 12'. After last weekend I'm getting 7-8' routinely. Does anyone have an explaination?

[+CYBret]

It happens to me every now and then too. Just consider it one of those happy little gifts from the satellite fairies.

 

Also, make sure you keep holding your mouth right.

 

Bret

 

"The kingdom of heaven is like treasure hidden in a field.

When a man found it, he hid it again." Mt. 13:44

[+phantom4099]

The EPE or accuracy reading on your GPSr is just a guess. YOu can have better or worse accuracy, the only way to test it is to go to a know location.

 

Wyatt W.

 

The probability of someone watching you is directly proportional to the stupidity of your actions.

[Couch_Potato]

As mentioned above, the EPE/accuracy reading on your GPSr is an approximation of the error in position. The calculation of which is very complex, involving the positions of the satellites, time of day, multipath delay, atmospheric conditions, amount of visible sky, surrounding landscape/architecture, position of sun and moon, which hand you hold the gpsr in, the flight path of the african swallow, and the flapping of a butterfly's wings somewhere in Asia. Well, maybe not all of those, but some of them do contribute to the EPE. Sometimes you just get lucky and everything aligns just right to yield a low EPE.

 

I'm not lost!

I just don't know where I am.

[+tonyjago]

quote:

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Originally posted by olcoon & Tigger2:

I bought a Garmin Map76s in March. Until this last weekend the best accuracy I could get was 12'. After last weekend I'm getting 7-8' routinely. Does anyone have an explaination?

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The longer you have the GPS switched on for, the more satellites it will know about and the better accuracy the location will be. I leave my GPS on in the car on the way to a cache so by the time I get there, all of the satellite orbits will have been updated in memory. This helps alot if the bush your traveing through has poor radio penetration.

 

Also, try swithing WAAS on or off depending on where you are. In Australia, the WAAS function of the 76S blows the accuracy way out, much better to have it switched off here. In the US it would be probably better to have it switched on.

 

The 76S can also average a waypoint when you record it. Hold down the "enter" key to mark a way point. When the waypoint information appears, press menu and select "Average Location". This should improve accuracy.

 

BTW, 12' is a good accuracy figure anyway

 

Tony

[olcoon & Tigger2]

Thanks for the answers! I kind of figured that it was something like I was standing 16.3 ft. from a white oak tree, on the north side with the wind blowing from the s.e. and passing gas to the tune of Dixie. I have noticed that sometimes I can turn WAAS off, and get better accruacy. I thought 12 ft. was doing pretty good, but after all they said "within 3 meters", so I beleived them. BTW, the tooth fairy is coming tonight, and I'm almost ready to send off my letter to Santa!