CRASH! Posted July 20, 2003 Share Posted July 20, 2003 Hey all, Brand spankin' new to the Geo cache hunt. I've got a Garmin V and last night went with a group of friends on my first hunt. At the first location, we got to the "parking area" just fine. When on foot trying to zero in on the exact coordinates, my unit gave a reading quite different than my buddies. My 0 foot mark was 187 feet off from his units dead on mark. Accuracy was within 14 feet according to the unit. We found the cache right near his mark. At the second cache hunt mine was off 150 feet from his and the location. So what gives? I would'a figured for a higher priced unit, it'd at least be somewhat accurate. 150 feet off is the difference between a fun hike and an all night excursion! This topic may have been covered, so sorry if so. But I'd like to hide a cache or two, but I'm hessitant to trust my unit. Am I doing something wrong? Or should I return this particular unit? Thanks in advance! Ride'on, ~CRASH!~ Quote Link to comment
TNRonin Posted July 20, 2003 Share Posted July 20, 2003 Are you all running the same datum? Etc... Have you sat your GPS out so it could get a good reading and settle down? Stuff like that. I've had similar issues with my sprotrak, but it usually settles down. Quote Link to comment
+Cadwalader Posted July 20, 2003 Share Posted July 20, 2003 Bear in mind that GPS signals from the satellites are about the equivelant of a 75 watt light bulb 12,000 miles away. That our little hand held units have sufficiently sophisticated electronics to differentiate that weak a signal at all amazes me. When you go under, near or behind any sort of object - tree trunk, bridge, leaves, etc., the signal is even weaker and less reliable. It is often desirable when caching to simply stop and hold the unit above your head for a minute or so to let it "settle down" and acquire the signal better and re calculate your position. The longer I let my Magellan Merdian sit still the more accurate it becomes. Good Luck Cadwalader & the Golden Horde Quote Link to comment
+hoys Posted July 20, 2003 Share Posted July 20, 2003 Have you loaded the latest firmware to your GPS? Garmin frequently comes out with updates that help the operation and accuracy of the units. Not saying that that would account for that much drift, but updated firmware can only help, if it's available. Also, how strong were your batteries? I have noticed reduced accuracy sometimes on my Venture when the batteries get a little low. As others have already mentioned, letting it sit and "settle" a little can help. Quote Link to comment
+carleenp Posted July 20, 2003 Share Posted July 20, 2003 Did you initialize your GPS? When I first first got my Magellan, it was off a lot until I initialized it (sorry, but I can't remember what that entailed). Then it was fine! Quote Link to comment
CRASH! Posted July 20, 2003 Author Share Posted July 20, 2003 Thanks for all the quick responses!! The batteries were new, changed them before I left the house. As for settling down, could be. Although I wandered around in a several hundred foot radius for awhile and my zero point remained the same. But... could be. As for the latest software... I just bought it, doesn't that count for anything?!? LOL I pro'lly should do that! Initializing... I was gonna write my initials on it, but decided not to. <har har> Haven't done that either. Any hints? any one, any one? Ride'on, ~CRASH!~ Quote Link to comment
Kerry. Posted July 20, 2003 Share Posted July 20, 2003 That difference has all the markings of a possible datum and/or position format issue. You were asked about the datum but haven't mentioned looking at that so validate both datum and position format are correct. Eliminate the simply things first. Cheers, Kerry. I never get lost everybody keeps telling me where to go Quote Link to comment
umc Posted July 20, 2003 Share Posted July 20, 2003 Or is could be that the V is junk. Well not totaly but I'm on my second V because the first one was doing what you mention. I would get right near the cache then it would tell me its 150 feet in another direction. It works great in the truck but I've had issues with it out from there. My second one seems to be better but I haven't used it or tested it as much as I did the first. I took the first one back to REI and told them that I think its a lemon. It also never held a lock. Let me look for the link to the thread where I posted all of my junk on the V. __________________________ Caching without a clue.... Quote Link to comment
umc Posted July 20, 2003 Share Posted July 20, 2003 Here is the link and know that its pretty long and drawn out and boring. __________________________ Caching without a clue.... Quote Link to comment
+Perrin Posted July 20, 2003 Share Posted July 20, 2003 Are you sure that the coords you put in were the right ones? I've mistakenly transposed or misread/entered numbers. I'm sure I'm the only one this has happened to, but who knows, maybe you are the second person to have that problem. It never hurts to double check your numbers. "Sometimes you are a very large fool Perrin Aybara. Quite often in fact." Annoura Sedai (Book Nine of The WoT) Quote Link to comment
+GatoRx Posted July 21, 2003 Share Posted July 21, 2003 Just a thought on this - doesn't the V have an 'on road' mode and an 'off road' mode? If the cache was close to pavement, and the GPS was set to the on road mode, that might explain it - its still trying to navigate based on roadways. Of course, if you'd hiked a mile in to find this one, I doubt that's it. ---- When in doubt, poke it with a stick. Quote Link to comment
+Renegade Knight Posted July 21, 2003 Share Posted July 21, 2003 My guess would be to check your datum. (Make sure you are WGS 84) Or if your buddy gave you the corrdinates he's not using NAD 27 or something else. Next is to make sure your using the right format. Geocaching.com uses DDD MM.MMM if you key in one format itno another you can pick up errors. ie DDD MM SS.SSS keyed in as DDD MM.MMM Your error is consistant so it's just a matter of figuruing out what it is. Then you will be rocking and rolling and your buddy can quit giving you so much flak (which all true friends would do in those circumstances) Quote Link to comment
+wimseyguy Posted July 21, 2003 Share Posted July 21, 2003 I'm pretty lotech with this stuff, but I was out on a 14 cache afternoon with a geopal two weeks ago.On several of the finds that afternoon we experienced that same variance on a few caches too. I think it's just satellite reception, nothing more. These changes in latitudes, changes in attitudes; Nothing remains quite the same. Through all of the islands and all of the highlands, If we couldn't laugh we would all go insane Quote Link to comment
+UFBuilder Posted July 21, 2003 Share Posted July 21, 2003 As I found at our local association meeting this last weekend, different brand GPSrs can produce very different coordinate locations. Someone in our group hid a cache in a location with a Magellan and I found it with my Garmin. We both used the same coordinates and I came up about 35' SW of the actual cache location. I know this doesn't approach your distances, but could contribute. The person that hid the cache with the Magellan said that Garmin users often mentioned this discrepancy when finding his caches. Quote Link to comment
+cachew nut Posted July 21, 2003 Share Posted July 21, 2003 quote:Originally posted by UFBuilder:As I found at our local association meeting this last weekend, different brand GPSrs can produce very different coordinate locations. Someone in our group hid a cache in a location with a Magellan and I found it with my Garmin. The person that hid the cache with the Magellan said that Garmin users often mentioned this discrepancy when finding his caches. Uh oh, here we go again. Quote Link to comment
umc Posted July 21, 2003 Share Posted July 21, 2003 quote:Originally posted by UFBuilder:As I found at our local association meeting this last weekend, different brand GPSrs can produce very different coordinate locations. Someone in our group hid a cache in a location with a Magellan and I found it with my Garmin. We both used the same coordinates and I came up about 35' SW of the actual cache location. I know this doesn't approach your distances, but could contribute. The person that hid the cache with the Magellan said that Garmin users often mentioned this discrepancy when finding his caches. Huh? __________________________ Caching without a clue.... Quote Link to comment
+EraSeek Posted July 21, 2003 Share Posted July 21, 2003 The distance off is highly suggestive of either have the wrong Datum set in your unit or inputing coords that are in another datum. Use WGS84 as your map datum in your unit. Input coords that using the same datum that your unit is set to. Coordinate format is the other possible. Other suggestions as software update, signal settleing in, will not make that big of difference. "See the wonderous works of Providence! The uncertainty of human things!" Geo.Washington Quote Link to comment
Kerry. Posted July 21, 2003 Share Posted July 21, 2003 Unless some like going around in circles actually posting more relevent information would eliminate much of the guessing with a lot of this stuff. Many want some answers but trying to extract some of the information gets rather difficult at times. Really distances in this case mean nothing without the coordinates/location as then it's rather easy to determine if it is (or not) a datum issue or a format issue or both and if not then move on to some other cause. Cheers, Kerry. I never get lost everybody keeps telling me where to go Quote Link to comment
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