Have I Made A Huge Mistake?

[+BenHuge'N'Juggs]

Ok, so I'm somewhat new to geocaching, not a complete novice, but close. I was so excited when I first found out about geocaching that I ran out and bought the coolest sounding one I could find. I got a Cobra GPS 1000 on Ebay for a little over 200 bucks. It seemed really cool at first, but the more I have used it on hikes and while looking for caches, the more I think it sucks.

 

Has anyone had any experience with these?

 

It just seems inaccurate to me. I'll be standing at the beach and it'll say my elevation is 500ft. Is that normal?

 

Does everyone but me have a really cool Garmin that gets them to within inches of the coordinates for the geocache they are looking for? It just seems like its always tracking around, even while I am standing still. Am I expecting too much from my $200 GPS?

[+Renegade Knight]

Nothing gets you to within inches.

 

Cobras don't have a good reputation.

[+Camping Hoosiers]

I don't know anything about your gps, however I own three Garmin's that I really like. What I do know about gps in general though is that NONE of them are going to put you within inches of a cache.

 

When I am seeking a cache I get as close as I can, usually within a few feet of the coordinates, then I stick the gps in my pocket and start searching. I assume that with the margin of error for my unit, combined with the margin of error for the hiders unit will probably have me searching a fifty foot circle for the cache.

 

There are so many variables that accuracy to inches is impossible.

 

So you might just be expecting too much from your gps.

[+tands]

Go caching with someone. If your unit gets you within 30 feet that's doing well. At that point, put your GPS away. Only Geoholic28's GPS finds caches. The cache is always where he puts his GPS down. But the rest of us switch to visual/cipher/detection mode at this point. You really start finding caches when you get your head out of the GPS. Make sure yours gets you in the neighborhood, then start looking with your eyes.

 

- T of TandS

[+ATMA]

We have the Legend units here. None of them will get me closer than a foot from a target even in the best of conditions. Yours is probably just as good as ours.

Garmin tells me I am 50 feet below sea level standing in the driveway. I put no faith in the altimeter in those things.

I have wondered about your unit and would like to know if waypoints can be uploaded into it like the Garmin. Just last night I saw some walk away deals on the Cobra.

Edited September 10, 2005 by ATMA

[+dkwolf]

Nothing gets you to within inches.

Ahh, not true. Granted, nothing we can AFFORD gets you within inches, but a survey grade differential system will put you on the head of a nail-horizontally at least. Vertically, it's still not as accurate as a total station or transit.

 

If I remember right, a 10m vertical accuracy is still doing pretty good for consumer-grade GPS units.

 

As for the Cobra... when it comes to electronics, I generally try to shy away from 'crossover' products--a company specializing in one type of equipment, making something completely outside of their normal product line. (ie Cobra radar detectors vs Cobra GPS) Granted, some of the technology is probably the same...but. I try to buy products from a company where that product is their main focus.

 

~Edit: I've always had to resist the temptation to 'borrow' one of our survey GPS units and get the EXACT coordinates of my caches, but somehow doubt I could easily walk out of the office with $20k worth of gear without anyone noticing...although the surveyor did mention it once...

Edited September 9, 2005 by dkwolf

[+wandererrob]

the altimeter may just need to be calibrated, even so they are only a ballpark number anyway.

 

As for the wandering when you're standing still, welcome to wonderful world of GPS. My eTrex Vista does it too, so does every other one I've seen to some extent. Like somebody already said, it'll get you within 30 feet or so, but then any GPS is going to bounce around a bit.

 

Best case, mine has been within 6 feet under almost magical conditions.

[+Wrench&Wench]

Two weeks ago I went over the continental divide at Rogers pass in Montana. The sign said elevation 5610 ft, so I thought it would be a good time to calibrate my altimeter to that number. A week later going back over same divide it registered 5637 ft. I was hoping for a number more accurate than that but I'm not concerned about it. btw mine is a gps60cs.

[+tands]

Aaah not true on that survey stuff pardner. I got buds who are Civil Engineers, and ...

the GPS gets them close, but then out come the level, sights and the rest. Why are there laser sights and levels, hmmm? Because GPS units are only relatively accurate and assume the world is round. Ok for repeat positioning, but sucky for absolute position. So the survey GPS gets you to where the non-survey GPS thought the hide was. Still off eh? Not many hiders using survey units anyways. But absolutely no surveyors depending on them to get 'within inches.' Also, the one thing they never use a GPS for is altitude. Again the whole earth is not round thing. And then there's High and Low pressure systems. Yes the altimeter's barometric. Finally, we took a Trimble survey unit out a while back. And turned it off and broke out the Vista well before we made the find.

 

- T of TandS

Edited September 9, 2005 by tands

[+Renegade Knight]

Nothing gets you to within inches.

Ahh, not true. Granted, nothing we can AFFORD gets you within inches, but a survey grade differential system will put you on the head of a nail-horizontally at least. ...~Edit: I've always had to resist the temptation to 'borrow' one of our survey GPS units and get the EXACT coordinates of my caches, but somehow doubt I could easily walk out of the office with $20k worth of gear without anyone noticing...although the surveyor did mention it once...

Ok, Ok true enough.

 

It would be interesting to see if it made any difference to locate your cache to that type of accuracy.

[+Isonzo Karst]

We used $20K worth of surveying equipment to set a point for a GPS accuracy game for an event - the particular unit we used would not give ANY information if it didn't like the satellite config or the tree cover. Kinda useless for geocaching.

BTW a majority of cachers placed their marks within 8 feet of the hidden mark - the winner was within 2 inches - and the only folks any real distance away had mis-entered the coords. This in an opened ball field with excellent satellite configuration and no clouds. No real brand name difference under those conditions.

[nobby.nobbs]

a couple of points. the search is half the fun, where's the excitement if you know for sure that the gps will sto you just as your boot hits the box? hardly engaging brain is it?

 

in uk i've actaully been getting locks +/- 2metres recently

 

i thought only people who got guarenteed high level of accuracy was military? mind you may aswell be other way around as the bombing accuracy figure are hopeless.

[+blindleader]

The sign said elevation 5610 ft, so I thought it would be a good time to calibrate my altimeter to that number. A week later going back over same divide it registered 5637 ft.

If I understand you correctly you didn't recalibrate in the intervening week? In that case you had an amazing stroke of luck having it read that close. In a week the local weather can change enough for the difference to be more than a thousand feet. The term altimeter is a misnomer. It's really a barometer with a readout in units of elevation. If you really want the altimeter to be useful in an ongoing way you need to calibrate it every few hours unless you are stuck in one of those dog day high pressure zones or some other extremely stable weather system.

[+dkwolf]

Aaah not true on that survey stuff pardner. I got buds who are Civil Engineers, and ...

the GPS gets them close, but then out come the level, sights and the rest. Why are there laser sights and levels, hmmm? Because GPS units are only relatively accurate and assume the world is round. Ok for repeat positioning, but sucky for absolute position. So the survey GPS gets you to where the non-survey GPS thought the hide was. Still off eh? Not many hiders using survey units anyways. But absolutely no surveyors depending on them to get 'within inches.' Also, the one thing they never use a GPS for is altitude. Again the whole earth is not round thing. And then there's High and Low pressure systems. Yes the altimeter's barometric. Finally, we took a Trimble survey unit out a while back. And turned it off and broke out the Vista well before we made the find.

 

- T of TandS

On the contrary, we DO use our survey unit for sub-inch accuracy. Almost weekly, in fact. TDS Recon data collector, couple different GPS units. The GPS's are differential base station/rover setups, where one antenna is placed on a tripod at a measured elevation above a KNOWN point. This antenna takes the satellite signals, triangulates the position and compares to the known position/elevation. It then computes a correction factor based on this and broadcasts it out to the rover unit, which triangulates ITS position from satellites and then adds the correction factor. Good for under 0.02' (that's right, two one-hundredths of a foot, less than 1/4") horizontal, and vertical I don't recall exactly, maybe within 0.04'. As for the whole "earth not being round", that's what ellipsoid models are for.

 

And yes, the survey units are INCREDIBLY picky. We've had tall corn block enough of the signal to lose survey-grade accuracy.

 

I'm guessing the Trimble unit you were using was NOT using differential corrections, hence the decreased accuracy--it was working just like your legend. (yes, our legends will indicate a differential signal from a satellite (the 'D' on the strength bar, but without a differential antennae, they can't do a dang thing with them)

[+Thrak]

Two weeks ago I went over the continental divide at Rogers pass in Montana. The sign said elevation 5610 ft, so I thought it would be a good time to calibrate my altimeter to that number. A week later going back over same divide it registered 5637 ft. I was hoping for a number more accurate than that but I'm not concerned about it. btw mine is a gps60cs.

Pretty darn close if you ask me.

[Pto]

When Ive brought people with me, trying to get them into caching - I give them the Gps'r - a Garmin Etrax Legend- they look at it, the arrow swirrling all over and say What?

 

Sometimes I break down to the "its down there, in the large group of trees. Go find it.

The trees cover over 100 ft squared, and they have found it - just by getting in the general area.

My wife found one of my caches while looking for something else (local area "capture the flag contest, by MN Wild Hockey) - I hadnt told her where my cache even was - but she pulled it out and said "What do you think this is?"

 

D'oh! She wont log it tho- shes not really into my hobby - just "reality TV", and MN Wild Hockey!

[+briansnat]

If you do a forum search on Cobra you won't find a whole lot of people with good things to say about them.

[+AtoZ]

Nothing gets you to within inches.

 

Cobras don't have a good reputation.

What RK said.

 

If it was any GPSr then the Cobra then I would have said don't sweat it, it will work fine but I have never heard agood thing about the Cobra for geocaching.

cheers

[+Mudfrog]

I havnt seen a Cobra unit in action but i think you ought to give it a chance. None of our handheld civilian type units will be precise. They are good for getting you close but wont consistently put you to within inches. I believe this is mainly due to the fact that the US government throws that accuracy error in on purpose.

 

What im getting at is that you need to get used to how your GPSr works. The more you use it, the better you will get with using it. I really believe you would be asking this same question no matter what brand of unit you had bought!

[+Sputnik 57]

If you do a forum search on Cobra you won't find a whole lot of people with good things to say about them.

Although that having been said, I've seen few bad comments about the Cobra 1000. Most complaints are about the Cobra 100 and 500.

[+Jeep_Dog]

Ah, Cobra GPSr. It has been mentioned several times, but I will state it again. Their reputation is not very good.

 

I introduced some family into geocaching, and went shopping for a GPSr with them. I was trying to coach them toward an Etrex, but would have nodded to a magellan as well.

 

Loh and behold, one of the places we stopped had a Cobra unit, that usually sells for around $200, for less than $100 (that should have been a clue) and about $10 less than an Etrex. It had some features that the Etrex lacked, such as a magnetic compass, and a couple of other features I do not remember. They were really excited about it, and the price, so that was the one they purchased.

 

We went off, and I was teaching them how to use a GPSr. After 45 minutes, the silly unit had only locked in on 2 satellites, with little hope of finding a third for a position in the forseeable future. I commented that perhaps the extra $10 bucks for an Etrex might be worth the investment, since I was not very impressed with Cobra by that point.

 

So, within an hour and thirty minutes, the Cobra was returned, and an Etrex purchased. Within 5 minutes out of the box and powered up, the faithful yellow was pulling in 6 satellites.

 

The only folks I would recommend a Cobra to are the local FTF hounds if they broke or lost their GPSr. Then again, they would probably know better....

[+dkwolf]

I believe this is mainly due to the fact that the US government throws that accuracy error in on purpose.

Nope, the US Government turned OFF Selective Availability a little over 5 years ago, which made civilian units much more accurate. From an EPE of 100m down to 10m overnight. Good enough that civilian units could now be used to find stuff hidden in random locations, which someone did. I believe it was a 5-gallon bucket with a can of beans in it?

 

The simple truth is that the military units are using differential correction systems for pinpoint accuracy. Differential systems are NOT cheap, in fact it is cost prohibitive for a civilian to own one. Think about this for a moment--the little plastic box in your hand is recieving a signal from a clock 12,000 miles up, and using the known position of that clock and the time shift to get to you, triangulating it's position. Pretty freaking amazing we can get a 7' EPE when you think about that.

[+BenHuge'N'Juggs]

Awesome, this was a HUGE help. Thanks for all of the info everyone. I really appreciate it.

[+Mudfrog]

Nope, the US Government turned OFF Selective Availability a little over 5 years ago, which made civilian units much more accurate. From an EPE of 100m down to 10m overnight. Good enough that civilian units could now be used to find stuff hidden in random locations, which someone did. I believe it was a 5-gallon bucket with a can of beans in it?

 

I knew that SA had been turned off a few years back thereby making civilian units more accurate. But i still was under the impression that there was some error being introduced at the present time as well. Im not sure why i was thinking that either. Thanks for the update.

[+Gozz]

your unit is just as good as anyone elses. Go out in your yard and mark some waypoints walk off 100' or so then using the little arrow go back, notice how far off it is over about ten times--under trees it will be worse.

[+Cryptid]

 

It just seems inaccurate to me. I'll be standing at the beach and it'll say my elevation is 500ft. Is that normal?

That depends, what is the Elevation of Sea level where your from?

[Zoptrop]

FWIW... my only complaint about the Cobra is the stupid, stupid, stupid "pop up" message that says "Arriving at Destination" (as if I'm too ignorant to know I'm within 100 to 50 feet of where I'm going.) You *have* to acknowledge the message and when you do, it "turns off" your search.

 

However (with a whole, whopping 30 finds under my belt) I've gotten brave enough that I can turn the gps off around 75 to 50 feet away and search on my own.

[+AtoZ]

Aaah not true on that survey stuff pardner. I got buds who are Civil Engineers, and ...

the GPS gets them close, but then out come the level, sights and the rest. Why are there laser sights and levels, hmmm? Because GPS units are only relatively accurate and assume the world is round. Ok for repeat positioning, but sucky for absolute position. So the survey GPS gets you to where the non-survey GPS thought the hide was. Still off eh? Not many hiders using survey units anyways. But absolutely no surveyors depending on them to get 'within inches.' Also, the one thing they never use a GPS for is altitude. Again the whole earth is not round thing. And then there's High and Low pressure systems. Yes the altimeter's barometric. Finally, we took a Trimble survey unit out a while back. And turned it off and broke out the Vista well before we made the find.

 

- T of TandS

WRONG suvery GPS can get down to cms. But it takes many hours of aquisiton time to get a valid reading. Theoadlites, Laser range finders etc... are valid to and may not be as accurate as a surver grade laser. I eorked my way through college suveying old school.

cheers

[+CSI:CacheSceneInvestigators]

My first gpsr was a cobra 1000. At that time I was not even aware of geocaching. When I found out about geocaching, I used the cobra 1000 for my first 5 caches. It worked great for me, but I couldn't download loc or gpx files to the gpsr or use GSAK or any other geocaching software, as they did not recoginize the cobra gpsr. With that in mind I went out a purchased a Gamin GPSmap 60cs and Garmin Legend. The cobra now sits in my desk. I'll keep it for my son when he gets older. I've used both the cobra and garmin units in a side by side comparison and both garmins capture satellites quicker, but as far as accuracy, all three are relatively close, well within the spec'd limits. I've even run into instances when under heavy tree cover, my expensive GPSmap 60cs looses the satellites while the much less expensive legend and cobra will keep reception.

 

It comes down to what you like, features you want and of course $$$$$$$$.

 

Good luck.

[+tands]

Everybody who surveys to cms with their GPS units please post locations of any dams, nuclear plants and such you do this with. I will stay away. Be afraid, very afraid. And.. . how do you know when your GPS is right after all those hours. Well what else are you gonna do but measure it with levels and such 100 times while you're waiting to be sure. I could use a $1000 computer to add 2 plus 2. But with booting up and firing up calc maybe I'm better off using my fingers.

 

- T of TandS

Edited September 10, 2005 by tands

[+dkwolf]

Everybody who surveys to cms with their GPS units please post locations of any dams, nuclear plants and such you do this with.  I will stay away.  Be afraid, very afraid.  And.. . how do you know when your GPS is right after all those hours.  Well what else are you gonna do but measure it with levels and such 100 times while you're waiting to be sure.  I could use a $1000 computer to add 2 plus 2.  But with booting up and firing up calc maybe I'm better off using my fingers.

 

- T of TandS

Got news for ya buddy. The government has been using GPS to build dams for AT LEAST 5 years (remember, prior to S/A being turned off, access to the error-free channel was restricted to military and approved government entities) In fact, in the fall of 1999, I toured an NRCS office through one of my college classes and got to look over a DGPS reciever system capable of 8mm accuracy. And the technology has advanced a great deal since then.

 

I have to say, I seriously question the GPS system your CivE 'buds' are using. FWIW, I work for one of leading civil and agricultural engineering consulting companies in our half of the state, and we have used GPS to survey and construction stake virtually every type of project we do, from highways to airport runways to railroads to processing plants. It's every bit as accurate as people here have told you. You really, REALLY need to do some research and reading on how a differential GPS system operates, and what it's capable of.

Edited September 10, 2005 by dkwolf

[+KiAyker]

I got into Geocaching as a result of a Cobra 1000 I received as a gift. Using the Cobra 1000 I managed to find my first 100 or so caches. Then I upgraded to a Garmin 60C. Finding caches with the Garmin is so easy it's almost ridiculous. I think a lot of that is the result of the skills I developed using the Cobra. The Cobra is no where near as easy as the Garmin is - it requires some interpretation. But as a first GPS I have to believe that the Cobra taught me a lot about how to find caches that a more sophisticated unit probably would not have.

I intended to continue using the Cobra from time to time, even after purchasing the Garmin, just to help keep me "sharp" on the game. But alas, the Cobra was stolen from my car, which was where I was keeping it. I have nothing but found memories of my Cobra, and would not hesitate to recommend it as a beginners GPS. That said, I REALLY LOVE my Garmin

[+tands]

Yes, you can land a 747 with GPS. If it were interfaced that GPS could be an Etrex Yellow. The point is the geekosterone-laden lustful 'ooh surveying GPS is so great' posts in a thread about a Cobra GPS. Like asking about a Honda Civic and having a bunch of posers bragging about their Porsches. Yeah Porsches are great. But they cost a lot to buy and own, are a royal pain over speed bumps, and are usually a compensation for some other shortcoming. Spare us from your unexplainable love of a GPS that takes hours to synch. Yeah they built the Ravenel Bridge in Charleston with GPS. They started from shore and in the middle and everything lined up when they met. But they weren't using it for cm measurements. It worked because everything averaged out and they backed it up by MEASURING. When you survey, do you certify down to the cm? Why would you? They measure the movement of the continental plates with GPS. Down to the mm. But not once a year. It is measured constantly and averaged. So why do you brag about that and argue that it's good for anything in a Geocaching forum? It doesn't make you any cooler that your company has a clunky impractical GPS device that does have its uses but is lousy for geocaching.

 

- T of TandS

Edited September 10, 2005 by tands

[+Prime Suspect]

I got into Geocaching as a result of a Cobra 1000 I received as a gift. Using the Cobra 1000 I managed to find my first 100 or so caches. Then I upgraded to a Garmin 60C. Finding caches with the Garmin is so easy it's almost ridiculous. I think a lot of that is the result of the skills I developed using the Cobra. The Cobra is no where near as easy as the Garmin is - it requires some interpretation. But as a first GPS I have to believe that the Cobra taught me a lot about how to find caches that a more sophisticated unit probably would not have.

I intended to continue using the Cobra from time to time, even after purchasing the Garmin, just to help keep me "sharp" on the game. But alas, the Cobra was stolen from my car, which was where I was keeping it. I have nothing but found memories of my Cobra, and would not hesitate to recommend it as a beginners GPS. That said, I REALLY LOVE my Garmin

How dare you try to keep the thread on track. Can't you see we've got people trying to derail it by arguing about dams locations and landing planes? Sheesh!

[+tands]

But alas, the Cobra was stolen from my car,

There ya have it, one segment of the populace, thieves, prefer Cobra GPS. - T

[+dkwolf]

So why do you brag about that and argue that it's good for anything in a Geocaching forum?  It doesn't make you any cooler that your company has a clunky impractical GPS device that does have its uses but is lousy for geocaching.

If you'll look back at the thread, this tangent began as a casual ribbing about 'nothing gets you within inches'. You're the one that took it from there, from that point I have only been trying to correct misinformation in your posts.

 

If you wish to continue this discussion, PM me. I do not wish to drag this particular thread further OT.

 

OP--best solution, take your Cobra out caching, see how it is going to work for you. Worst case, unload it on Ebay again and pick up and Etrex.

 

EDIT: Oddly enough, I drive a Honda Civic....

Edited September 10, 2005 by dkwolf

[+tands]

EDIT: Oddly enough, I drive a Honda Civic....

Well there goes my theory about 'compensating.'

 

Peace. I'm sorry for going so overboard.

 

I think I'll go ride in my Porsche and chill out.

 

On topic: I have friends who do fine caching with Cobra GPS units. I have a friend who is one of the best cachers I know who uses an Etrex Yellow, and he doesn't have a PC cable and never uses one. So that's not a necessity either. We have a 60CS, but we're buying a basic (but no less capable) unit soon, and we're considering all of them including Cobra and Lowrance. Expensive GPS units often get in the way cuz you're looking at the bells and whistles instead of the surroundings at the cache site.

 

One thing I'd recommend no matter what GPS you have is getting some of those new IC3 batteries and a charger. They charge in 15 minutes and last longer per charge for us than single-use lithium batteries.

 

- T of TandS

Edited September 10, 2005 by tands

[+dkwolf]

Peace. I'm sorry for going so overboard.

Agreed, and likewise.

 

OP--Welcome to the sport, hope it brings you as much fun and enjoyment as it does everyone else here.

[+hikergps]

Does everyone but me have a really cool Garmin that gets them to within inches of the coordinates for the geocache they are looking for?

 

Mine isn't a Garmin but it puts me to within inches, about 360 inches. Here is what I have. Got it on ebay for less than $35 including the shipping.

 

 

Kind of looks like a brick w/buttons. I have only had 2 dnf, both because I wasn't looking hard enough. I wouldn't have done any better with a new unit. The GPS is only part of the hunt. I don't consider myself a veteran yet but thought I'd toss my .02 in anyhow.

Edited September 10, 2005 by hikergps