Using Waas

[+fersman4]

My manual says that in order to use WAAS you need to have acquired satelites numbered 33 and above. Is this still accurate? In other words, if I have WAAS enabled and have synched with a satelite numbered 33 or above and have a clear view of the sky and have waited 10-20 minutes (wait I need to take a breath), then I will be using WAAS and getting more precise readings?

 

The manual says to point the antenna toward the satellite. Which way does may eTrex Legend antenna point?

[peter]

The manual says to point the antenna toward the satellite. Which way does may eTrex Legend antenna point?

The Legend should be held approximately horizontal so the flat plate of the patch antenna under the Garmin logo is facing the sky.

 

Yes, WAAS satellites are assigned numbers above 32. You can see if you're getting the corrections by looking at the satellite page. Any satellites for which the unit is using the correction data will have a little "D" (for differential) on the signal strength bar.

[+Poindexter]

It would be similar to this screenshot of my Garmin Map76S

 

[cajungeo]

I'm neo to geocaching. I have a E Trex Legend with WAAS enabled. I still don't get the "D" in the signal strength bars? Could it be my location (Florida, Orlando)?

[+Cardinal Red]

Look above for the Screenshot provided by Poindexter. His location at that moment is Maryland. Actually he could be in a boat on the Chesapeake Bay. It's a bit cold for that right now, isn't it? What he didn't specify is that #35 is the WAAS Satellite. You can see it is at about 45 Degrees elevation on the horizon, in a Southeast direction. Anywhere in the U.S. Mainland, Satelite #35 will generally be in a Southeast direction. Find an open spot with a clear view to the Southeast to attempt your first WAAS reception. And give it time! I got tired of waiting the very first time and just left it sit for half an hour. When I went back, I had it.

 

This is taken from the book A GPS USER MANUAL (WORKING WITH GARMIN RECEIVERS) by Dale DePriest. "From the west coast of the US you can access (Satellite) number 47 and (Satellite) number 35 while from the east coast you can only see number 35." "Find a clear sky view in the direction of the WAAS GEO satellites you are interested in. If necessary set a waypoint to their approximite location so that you can use the GPS itself to provide a bearing to the satellite. GEOS 35 is at Lat 0 and Lon 54 West (somewhere over Brazil) while 47 is at Lat 0 and Lon 179 West (very nearly over Howland Island)." Remember Amelia Earhart? The very thing that could have saved her life, now orbits over the destination she was trying to reach.

 

Not sure if this is Garmin specific or not. " Be sure that your GPS is set normal mode (not battery save) for this procedure. The nature of WAAS corrections precludes it's use in Garmin battery save mode."

[CharlieBull64]

Yes very true what Cardinial Red said. On your garmin legend make sure its not in the battery saver mode. It will not enable WASS in this mode. Change it to NORMAL which will update the sats more often and enable WASS

It is also in your manual

[+fersman4]

You guys ROCK! Thanks. Unfortunately, at my lattitude (37+) 35 and 47 seem to be just above the horizon. I'll give it a try, though.

[cajungeo]

Thanks for the tip! Just took a little patience and now "D's' everywhere!

[CharlieBull64]

I did the same thing, had my legend for two weeks and never had WAAS to engage. So back to the manual I went, and there it was in black and white " put it on normal stupid" I should have read it sooner. Waas is incredable I can get down to accuracy of 7' . cheers

[cajungeo]

I've been reading the manual... haven't attempted to find a cache yet, getting familiar with my Legend. Should I try to manually enter the cordinates or use easyGPS or SAK?

[+Sputnik 57]

I've been reading the manual... haven't attempted to find a cache yet, getting familiar with my Legend. Should I try to manually enter the cordinates or use easyGPS or SAK?

I used to manually enter my coordinates into my Garmin 12. My girlfriend looked over my shoulder to make sure I had them right. This frequently lead to accurate coordinates, but considerable delays before we went caching .

 

Now I have a 60C, and load caches from GSAK. I have lots more waypoints in my GPSr, but it isn't nearly as fun.

[+fersman4]

You should get very familiar with manually entering waypoints and using your legend. This means finding a dozen or so traditionals and multis. After you have one or two dozen under your belt, you will really understand how to use the GPS well, then there's no harm in going to something like EasyGPS or GSAK.

[Z15]

Could it be my location (Florida, Orlando)?

 

I am way North in Michigan on Lake Superior and I can track SV35 on my Garmins. But you do need a clear view about 15° above the horizon, if a building or trees is are in the way, you are SOL.

 

The manual says to point the antenna toward the satellite. Which way does may eTrex Legend antenna point?

 

Antenna is a the top end of unit.

 

WAAS consists of approximately 25 ground reference stations positioned across the United States that monitor GPS satellite data. Two master stations, located on either coast, collect data from the reference stations and create a GPS correction message. This correction accounts for GPS satellite orbit and clock drift plus signal delays caused by the atmosphere and ionosphere. The corrected differential message is then broadcast through one of two geostationary satellites, or satellites with a fixed position over the equator. The information is compatible with the basic GPS signal structure, which means any WAAS-enabled GPS receiver can read the signal.

 

Currently, WAAS satellite coverage is only available in North America. There are no ground reference stations in South America, so even though GPS users there can receive WAAS, the signal has not been corrected and thus would not improve the accuracy of their unit. For some users in the U.S., the position of the satellites over the equator makes it difficult to receive the signals when trees or mountains obstruct the view of the horizon. WAAS signal reception is ideal for open land and marine applications. WAAS provides extended coverage both inland and offshore compared to the land-based DGPS (differential GPS) system. Another benefit of WAAS is that it does not require additional receiving equipment, while DGPS does.

Edited January 30, 2005 by elcamino

[+HHL]

happy hunting.

[cajungeo]

Found my first cache today! Had my son as wingman, reading the coordinates while i drove. Entered coordinates manually... learning a little more each time I use the Legend.