E-trex Vista Wows

[+bob393]

My Vista is about 3 years old and it has served me well. It is also updated to the current software. Yah it's been droped, yah the screen lines out occassionally and a tap fixes it.

 

Now the last 4 or 5 caches I seem to be getting a 50 to 100 foot discrepancy from ground zero. Several of the previous cache notes had complimented the hider on the accuracy of the co-ordinances posted. On one I actually met up with two other cachers and when we found the cache theirs was right-on and mine was 50 foot off.

 

I planted a new cach last weekend and the first log was a could not find. And I triple checked those co-orninances for ground zero.

 

I'm just wondering if anyone else has seen or had this problem?

[+webscouter.]

I wonder if during an update the Datum got changed, or maybe you accidently changed it yourself. I have done some changes without realizing it when I try to drive and search for a nearest waypoint while counting button pushes. I have hit the wrong button and got into the wrong menu.

[+bob393]

That would be a good one,

I've done it myself but I did check that, WGS84 it is.

It was worth checking again, thanks.

[+GeckoGeek]

The first thing to do is make sure the unit has been able to download all the information it can use. A good 20 minutes or so with clear sky should do the trick. You may want to do a full reset first so as to remove old data.

 

Reflashing the firmware might not be a bad idea either.

 

Also check what you're EPE is. That will tell you how your unit thinks it's doing.

 

But first you need to know what you're real error is. Either to confirm the problem, or to know that it's been solved. The best way to do it is find a local BenchMark where it says the location is ADJUSTED. Avoid SCALED marks as they are good for calibrating your altimeter, but not for knowing where you are.

Edited March 14, 2004 by GeckoGeek

[+bob393]

20 min. eeks!

 

What's EPE? Don't know that one.

 

Good idea though, I will reflash the firmware tonight before I use it on Sunday, and find a benchmark to confirm or deny with.

Thanks.

[+Alan2]

Just a thought Try new batteries , make sure it's not on battery saver mode.

 

Hit it again..

 

Alan

[+bob393]

Alen actually the batteries were a little on the low side. I changed them.

I just re-flashed the firmware to 3.60 and re-loaded the waypoints soooo I'm ready for Sunday's benchmark test.

And I did hit it several times more.

Oh definately not on battery saver mode.

Thanks

[+GeckoGeek]

20 min. eeks!

 

 

Good idea though, I will reflash the firmware tonight before I use it on Sunday, and find a benchmark to confirm or deny with.

Thanks.

Well, that's just making sure. Do wait until all the bars on the satellite page goes black and the EFE gets down to 15ft or better. The unit needs to download all the latest information from the satellites and that may take some time. DO try and leave the GPS on as much as possible. DON'T just turn it on when you want a position reading. It may not have enough time to get a full download. This is where rechargeable batteries is a real plus since you don't care about running down rechargeable.

 

What's EPE? Don't know that one.

I think it's Estimated Position Error. (Someone will correct me if I guessed wrong). If your GPS is like my Geko, it's at the very top of the satellite page. It's an indication of how large it thinks the error may be. Smaller numbers are better.

[+RockyRiver]

Turn WAAS off. And let unit sit for 5 to 8 Minutes. If you are in a low spot or near rock or a lot of tree cover WAAS will throw you off sometimes. The small built in antenna on the etrex series does not pick up very good if there are any obsticles in its way such as trees and hills, This will cause a poor accuracy readings. The little etrex do good in the wide open but throw in a little interferance and they drop accuracy fast.

Edited March 14, 2004 by RockyRiver

[+bob393]

Your right about the rechargeable batteries, they do save a ton of money. I’ve been using them for a couple of years now. I just wish they had better charged shelf life.

 

I turn the GPS on when I leave the house so it can start acquiring satellite reception on the way to my first cache and it stays on the entire trip, sometimes eight hours or so.

 

EPE; I didn't know that one but I had a feeling you were talking about he accuracy numbers on the satellite reception screen.

 

It sounds like I use my GPS pretty much the way you describe.

When I plant a new cache I like to approach ground zero from several different directions and mark it from each one. I like to let the GPS sit on a rock for a while until the EPE drops as low as it will go. Unfortunately most of the caching here in the Northeast is in the woods with heavy tree cover, or in the mountains and valleys where signal bounce and foliage blocking is a real problem. Than I go back and check what the GPS is doing as I re-approach it from each of those directions. Than I choose the co-ordinances that have the most accurate zeroing on the cache.

I have been intensely frustrated at caches where the final co-ordinances were off by many hundred feet and after you hike several miles and pick off many ticks, well lets just say it takes some of the fun out of the sport

.

Thanks, I’m checking the unit’s accuracy this morning with a benchmark and I’ll let you know what happens.

[+bob393]

RockyRiver: Thanks

 

I will try it with the WAAS turned off. I had been leaving it on thinking it would make the unit more accurate. I do know it made the satiellite acquisition slower.

[+BlueDeuce]

If the batteries get too low on my Vista, it suddenly loses it's brain whenever I get within 100 feet of a waypoint. It can't decide where it point to and it'll even point at something 26 miles away! But farther away than 100 feet it points correctly. The remedy is to change the batteries and recalibrate the compass. Then it gets 'smart' again. (Just changing the batteries doesn't do it).

 

Edit: typos

Edited March 14, 2004 by Elf Danach

[+E = Mc2]

Almost said something about getting a Magellan there...

 

I've got an eTrex and a Meridian. For an eTrex under any type of cover, I don't expect much better than 30 ft accuracy. Tell the truth, when I get within about 30-50 feet of a cache, I don't even look at the recievers much anymore.

 

Probably not much help, I know. Hey! How about you splurge and get a 60c?! Then you can let the kids have the Vista to play with. Now, just how do I turn off WAAS again?

[+bob393]

Elf Danach:

How true it is!

I hadn't thought about it much but I have seen that behavior before, even the cold seems to effect it. I will use a fresh set of batteries.

Thanks

[+bob393]

E=Mc2:

I havn't thought to much about the 60c but I am real interested in the new 76cs or even the 76s if I cheep out.

[+bob393]

OK here is how it went.

 

I found a local Benchmark, PID LY2047, one that was verified for GPS accuracy. http://www.ngs.noaa.gov/cgi-bin/ds_radius.prl

http://www.ngs.noaa.gov/cgi-bin/ds_lookup....Item=DSDATA.TXT

 

Armed with this information, a GPS with re-flashed firmware, fresh batteries, and WAAS turned off, I headed out to find the Benchmark. Like a homing pigeon it went straight for it. At ground zero I was about 6 feet with an EPE of 16 feet. Right on!

Anyway I feel my problem was either Batteries or Firmware or both.

 

I highly recommend that everyone visit this page.

http://www.ngs.noaa.gov/cgi-bin/ds_radius.prl

You should find a local benchmark, and stick it in your GPS as a waypoint. That way when you get nervous about your GPS accuracy, or your caching ability, you can go check for yourself. Please note that the input format is DEG MIN SEC, and not our normal DEG MIN.Decimal, and when you download The NGS Data Sheet, The Co-ordinances are in Datum NAD 83 and not our standard WGS84. If you change the settings on your GPS before you input the information and then change it back to our standard the GPS should do the conversions for you, at least my eTrexVista did.

 

Thanks for all the help

Bob393

Cache-on