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GPS "Compass" Anomaly


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A strange thing happened while caching.

 

My wife and I were doing geo-art caching in the Mojave Desert (the Route 66 logo - GC3NR77, etc.). We each had a Garmin 60CSX. After finding a cache, we'd head toward the next one using the compass arrow on the GPS. Most caches were about 600 feet apart across open desert. As we'd get to about 200 feet from the next cache, the arrow would start to veer as much as 45 degrees. We'd alter course and keep walking. The arrow would continue to veer and we'd continue to alter course. This would happen with cache after cache. Often, we'd actually pass the cache by 60 or 70 feet and have to swing back for it.

 

We calibrated the compasses.

 

(I finally gave up on the compass and walked a line based on the display in map view. That worked very well and got me within 50 feet, at which time, I'd rely on the compass.)

 

Any ideas why the compass was doing this?

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A strange thing happened while caching.

 

My wife and I were doing geo-art caching in the Mojave Desert (the Route 66 logo - GC3NR77, etc.). We each had a Garmin 60CSX. After finding a cache, we'd head toward the next one using the compass arrow on the GPS. Most caches were about 600 feet apart across open desert. As we'd get to about 200 feet from the next cache, the arrow would start to veer as much as 45 degrees. We'd alter course and keep walking. The arrow would continue to veer and we'd continue to alter course. This would happen with cache after cache. Often, we'd actually pass the cache by 60 or 70 feet and have to swing back for it.

 

We calibrated the compasses.

 

(I finally gave up on the compass and walked a line based on the display in map view. That worked very well and got me within 50 feet, at which time, I'd rely on the compass.)

 

Any ideas why the compass was doing this?

 

Would you say that you and your wife have magnetic personalities? (yes, I know, the 60Cxs has an electronic compass)

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We calibrated the compasses.

Where did you calibrate them? While you were standing out in the open, or while you were in/at your car? The metal in the car can significantly affect compasses.

 

The fact that both were doing the same thing makes me think there may be some kind of setting that's causing it, but I can't think of what that might be. Were they both doing exactly the same thing?

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I had a Garmin with sensors and figured out pretty quickly that the compass was more of a pain than it was helpful. It's rediculous that the unit has to be calibrated every time the batteries are changed. It certainly didn't help with finding caches so i turned it off and never looked back. I have a couple of friends now that try leaving the compass on (one's a 60csx and the other a 76csx) and they are always complaining about the arrow pointing the wrong way.

 

My advice, turn the compass off. The batteries will probably last longer too!

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It's rediculous that the unit has to be calibrated every time the batteries are changed.

The manual for my Oregon says that, too, but I find I don't need to. I find it stays calibrated for roughly 10 or so battery changes. It'll stay perfect, then one time be completely off and/or non-responsive. A quick calibration, and it's good for a while longer.

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I had a Garmin with sensors and figured out pretty quickly that the compass was more of a pain than it was helpful. It's rediculous that the unit has to be calibrated every time the batteries are changed. It certainly didn't help with finding caches so i turned it off and never looked back. I have a couple of friends now that try leaving the compass on (one's a 60csx and the other a 76csx) and they are always complaining about the arrow pointing the wrong way.

 

My advice, turn the compass off. The batteries will probably last longer too!

 

It's why I've never bought one with an electronic compass, too many issues :)

 

At least using the GPS derived compass I know it is always pointing in the right direction as long as I'm moving slightly.

Edited by sussamb
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the 60 CSX is known to have a buggy compass

you need to calibrate it often, and need to hold it flat, display horizontally up,

I used to have a 60 CSX before it blew up, and I got a 62ST

it is a little bit better, but can also do bad things on the compass,

I get tired of calibrating it all the time for perfect behaviour,

so the trick is not to rely too much on the arrow, but more on the distance value to GZ,

it is easy to get that value to zero, pack away GPS, and use the secret force of seeking :-)

 

the slower you walk, the more buggy the arrow gets

Edited by OZ2CPU
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The batteries were fine. We calibrated the two units out in the open, in the area where we were caching.

 

I wouldn't worry about the batteries. In case the compass works better with good batteries - which I doubt, then that's a misdesign.

 

I was never a fan of electronic compasses, but the compass on my $100 smartphone still works much better than the one in the eTrex 30, and this without any need for active compass calibration. Now, the former in contrast to the latter does not see battery replacements, so perhaps the comparison is unfair, but anyway...

 

Both are however "thrown off" much easier than a real magnetic compass with inertia, at the end of the day a silva works much better.

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I cached for 9 years with a Magellan Meridian Platinum which has a perfect 3-axis electronic compass. I never knew what the fuss was about.....why wouldn't you want a unit to always point right at the cache even if you were standing still or moving slow ( no drunk walk ). Problem was the compasses in other units were buggy...the CSx works well 90% of the time but will, on occasion, need field calibration. With early firmware the 62S and 450 had problems.....currently, with firmware updates, they perform beautifully. I think the Etrex 30 still has major compass issues. Compass calibration is dependent on voltage ( battery charge/quality & charger performance ). With new 2500 Eneloops properly charged you can change batteries and not need to recalibrate , however it only takes about 30 seconds to calibrate a compass so why not just do it.

I have dozens of units of all types and I can say if you haven't cached with a unit with a GOOD 3-axis compass you don't know what you're missing.

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Quite a while back we had a chap with similar problems, and I made a suggestion it might have to do with his clothing. He was experimenting but never had further contact with his results. It was not a guarantee, just a suggestion to try.

 

Read this one if interested

 

I made that suggestion back then because I sometimes was running into problems with my regular compass until I realized what was happening... but there can be other factors as well. You just have to experiment.

Compasses react to many items and em fields they encounter. Up to the user to assess. Of course you can always simply avoid using it. I just use distance, bearing and accuracy displays to hunt, although I do use the bearing with my hand compass when needed.

 

Doug 7rxc

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I cached for 9 years with a Magellan Meridian Platinum which has a perfect 3-axis electronic compass. I never knew what the fuss was about.....why wouldn't you want a unit to always point right at the cache even if you were standing still or moving slow ( no drunk walk ). Problem was the compasses in other units were buggy...the CSx works well 90% of the time but will, on occasion, need field calibration. With early firmware the 62S and 450 had problems.....currently, with firmware updates, they perform beautifully. I think the Etrex 30 still has major compass issues. Compass calibration is dependent on voltage ( battery charge/quality & charger performance ). With new 2500 Eneloops properly charged you can change batteries and not need to recalibrate , however it only takes about 30 seconds to calibrate a compass so why not just do it.

I have dozens of units of all types and I can say if you haven't cached with a unit with a GOOD 3-axis compass you don't know what you're missing.

 

This!

I have to calibrate my 60CS a few times throughout the battery life as the voltage drops. No big deal. The benefits of using it far outweigh having to calibrate it two or three times during an eight hour caching hike. Things I have learned are not to calibrate it standing next to my car or next to a chain link fence.

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The benefits of using it far outweigh having to calibrate it two or three times during an eight hour caching hike. Things I have learned are not to calibrate it standing next to my car or next to a chain link fence.

 

Still waiting for someone to explain the benefits or as Bamboozle said 'you don't know what you're missing'.

 

Can someone explain what exactly I'm missing and/or the benefits that would warrant me spending extra on a GPS with a 3 axis compass? I've hiked and cached for many years and never felt the need for one, and all that seems to be posted about them is problems with calibration, not working properly, I keep mine switched off etc. A 'compass' derived from my GPS the minute I walk a few steps gives me a bearing that I know is accurate, what more can I possibly want?

Edited by sussamb
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I've a 3 axis compass and would be without it, but that said I've only used at etrex H (the only GPS I have without a compass) a couple of times so I guess it's what you get used to.

 

For me I like walking toward a cache, and if you stop to look and have a scout about, then the arrow still points in the right direction and doesn't do a merry dance.

 

As for calibration I only do it every now and again, it's not really an issue.

 

 

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The benefits of using it far outweigh having to calibrate it two or three times during an eight hour caching hike. Things I have learned are not to calibrate it standing next to my car or next to a chain link fence.

 

Still waiting for someone to explain the benefits or as Bamboozle said 'you don't know what you're missing'.

 

Can someone explain what exactly I'm missing and/or the benefits that would warrant me spending extra on a GPS with a 3 axis compass? I've hiked and cached for many years and never felt the need for one, and all that seems to be posted about them is problems with calibration, not working properly, I keep mine switched off etc. A 'compass' derived from my GPS the minute I walk a few steps gives me a bearing that I know is accurate, what more can I possibly want?

 

@Sussamb, I absolutely and totally agree (with your assessment)! I don't believe anyone will be able to give you a good reason,...... because there isn't one , except for instant gratification convenience and "bragging rights"...HA !

 

"They" talk about how important it is that the compass points to the cache while they are stopped. Well, DUH, they can't "get there" while they are stopped anyway....so.....????

I'm assuming they were moving the correct direction BEFORE stopping, so unless they have extremely poor short term memory, they should still know which direction they need to go when they start again.

 

......and besides, the number of forum posts would drop dramatically if you took away the "compass" (and best battery?)posts.

 

There are WAY more people that DO NOT know how to use their E compass than there are that DO KNOW.

 

If users learned how to use their GPS (with the compass turned off) FIRST then later turned them on, they would be VERY surprised.

Edited by Grasscatcher
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The benefits of using it far outweigh having to calibrate it two or three times during an eight hour caching hike. Things I have learned are not to calibrate it standing next to my car or next to a chain link fence.

 

Still waiting for someone to explain the benefits or as Bamboozle said 'you don't know what you're missing'.

 

Can someone explain what exactly I'm missing and/or the benefits that would warrant me spending extra on a GPS with a 3 axis compass? I've hiked and cached for many years and never felt the need for one, and all that seems to be posted about them is problems with calibration, not working properly, I keep mine switched off etc. A 'compass' derived from my GPS the minute I walk a few steps gives me a bearing that I know is accurate, what more can I possibly want?

 

@Sussamb, I absolutely and totally agree (with your assessment)! I don't believe anyone will be able to give you a good reason,...... because there isn't one , except for instant gratification convenience and "bragging rights"...HA !

 

"They" talk about how important it is that the compass points to the cache while they are stopped. Well, DUH, they can't "get there" while they are stopped anyway....so.....????

I'm assuming they were moving the correct direction BEFORE stopping, so unless they have extremely poor short term memory, they should still know which direction they need to go when they start again.

 

......and besides, the number of forum posts would drop dramatically if you took away the "compass" (and best battery?)posts.

 

There are WAY more people that DO NOT know how to use their E compass than there are that DO KNOW.

If users learned how to use their GPS (with the compass turned off) FIRST then later turned them on, they would be VERY surprised.

 

First. I don't know what bragging rights has to do with a discussion on E compasses, but I underlined your statement that I find to be absolutely true. I think this is why it is a constant source of discussion and why so many are so quick to simply say, "I turned it off, it didn't work".

 

I found my first 1500 or so caches with an old blue Legend that would only point to the cache if I was moving, so I do know how to use a gps and find caches without a E compass. While caching, I have found myself in areas where it is impossible to start walking at 3 MPH and have the GPS use the satellites to guide the way. Many times, I have to set my GPS on the ground and have it point the way and then start climbing. I find that keeping it calibrated and understanding how it works is a benefit when I am way out in the mountains.

 

One thing that I think messes a lot of people up is that, (if I remember correctly), the default setting on the 60's is to have the E compass take over if you are moving less than 3 MPH. 3 MPH is a brisk walk. The average hiker is going about 2-2.5 MPH, so the compass is always on and if it isn't properly calibrated, or with a 2 Axis compass, not held level, you get wonky readings. I set mine to 1 MPH, so most of the time, I'm not really even using it. It's when I get into thick brush, or climbing over boulders, I want to make sure that I'm heading in the right direction.

 

As far as answering the other's question, I'm not sure what the question is. If it's why use the E compass, I hope I just answered it. If it's why use a 3-axis compass, it's because you don't have to hold the unit level to get it to operate correctly. The Garmin 60's are all 2-axis and have to be held level when calibrating and using them.

 

Which brings up another thing. I have watched people try to calibrate their Garmins by holding it in their hands and trying to spin it. The problem is that they are wobbling it all over the place and not keeping it level. I had a friend that simply couldn't get his 60CSX to work properly, so I took it, held it level while I rotated my entire body for two circles. The compass was perfect worked for the first time since he had owned it. Now, when necessary, he does the same routine and has never had trouble.

Edited by Don_J
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The benefits of using it far outweigh having to calibrate it two or three times during an eight hour caching hike. Things I have learned are not to calibrate it standing next to my car or next to a chain link fence.

 

Still waiting for someone to explain the benefits or as Bamboozle said 'you don't know what you're missing'.

 

Can someone explain what exactly I'm missing and/or the benefits that would warrant me spending extra on a GPS with a 3 axis compass? I've hiked and cached for many years and never felt the need for one, and all that seems to be posted about them is problems with calibration, not working properly, I keep mine switched off etc. A 'compass' derived from my GPS the minute I walk a few steps gives me a bearing that I know is accurate, what more can I possibly want?

 

If all your caching is along a garden path, clear field, parking lots, etc you won't get the max. enjoyment out of the compass but its still better....quite often when reaching GZ a GPS unit will adjust...you'll see the pointer slowly move say to your right 15' to where the cache is...with no compass you have to start walking in any ( usually wrong) direction ( drunk walk ) to see the units corrected guidance.

The compass really shines, though, in tough terrain. If you're climbing rocks or on a steep hill covered with briars, bushes, and overhanging limbs or you're plodding through a swamp it can be hard to walk at all much less fast enough for a trad. GPS to guide you.

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The benefits of using it far outweigh having to calibrate it two or three times during an eight hour caching hike. Things I have learned are not to calibrate it standing next to my car or next to a chain link fence.

 

Still waiting for someone to explain the benefits or as Bamboozle said 'you don't know what you're missing'.

 

Can someone explain what exactly I'm missing and/or the benefits that would warrant me spending extra on a GPS with a 3 axis compass? I've hiked and cached for many years and never felt the need for one, and all that seems to be posted about them is problems with calibration, not working properly, I keep mine switched off etc. A 'compass' derived from my GPS the minute I walk a few steps gives me a bearing that I know is accurate, what more can I possibly want?

 

@Sussamb, I absolutely and totally agree (with your assessment)! I don't believe anyone will be able to give you a good reason,...... because there isn't one , except for instant gratification convenience and "bragging rights"...HA !

 

"They" talk about how important it is that the compass points to the cache while they are stopped. Well, DUH, they can't "get there" while they are stopped anyway....so.....????

I'm assuming they were moving the correct direction BEFORE stopping, so unless they have extremely poor short term memory, they should still know which direction they need to go when they start again.

 

......and besides, the number of forum posts would drop dramatically if you took away the "compass" (and best battery?)posts.

 

There are WAY more people that DO NOT know how to use their E compass than there are that DO KNOW.

If users learned how to use their GPS (with the compass turned off) FIRST then later turned them on, they would be VERY surprised.

 

First. I don't know what bragging rights has to do with a discussion on E compasses, but I underlined your statement that I find to be absolutely true. I think this is why it is a constant source of discussion and why so many are so quick to simply say, "I turned it off, it didn't work".

 

I found my first 1500 or so caches with an old blue Legend that would only point to the cache if I was moving, so I do know how to use a gps and find caches without a E compass. While caching, I have found myself in areas where it is impossible to start walking at 3 MPH and have the GPS use the satellites to guide the way. Many times, I have to set my GPS on the ground and have it point the way and then start climbing. I find that keeping it calibrated and understanding how it works is a benefit when I am way out in the mountains.

 

One thing that I think messes a lot of people up is that, (if I remember correctly), the default setting on the 60's is to have the E compass take over if you are moving less than 3 MPH. 3 MPH is a brisk walk. The average hiker is going about 2-2.5 MPH, so the compass is always on and if it isn't properly calibrated, or with a 2 Axis compass, not held level, you get wonky readings. I set mine to 1 MPH, so most of the time, I'm not really even using it. It's when I get into thick brush, or climbing over boulders, I want to make sure that I'm heading in the right direction.

 

As far as answering the other's question, I'm not sure what the question is. If it's why use the E compass, I hope I just answered it. If it's why use a 3-axis compass, it's because you don't have to hold the unit level to get it to operate correctly. The Garmin 60's are all 2-axis and have to be held level when calibrating and using them.

 

Which brings up another thing. I have watched people try to calibrate their Garmins by holding it in their hands and trying to spin it. The problem is that they are wobbling it all over the place and not keeping it level. I had a friend that simply couldn't get his 60CSX to work properly, so I took it, held it level while I rotated my entire body for two circles. The compass was perfect worked for the first time since he had owned it. Now, when necessary, he does the same routine and has never had trouble.

 

I agree with all.

Its like trying to explain an automatic transmission to someone who has only used a manual one. They would say the manual one works fine for me and gets me where I'm going ( and it does ).......the automatic one sure does it a lot easier.

 

Keep in mind 90% of the negative compass postings stem from either faulty early firmware on newer units or target the CSx which is a 2 axis compass which I found pretty good but a bit quirky.

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Well I've driven automatics and manuals (stick shifts) and I far prefer a manual :)

 

No one yet has been able to explain the benefit(s) of an electronic compass. If it's so great how come no one can do so?

For me it's not the type of compass available (assuming it is in working condition) but the fact of having one available to use when needed. No one without a working knowledge of it's use will get the best out of it.

 

Since I own good discrete compasses, I don't need to buy the added feature of one on the GPS.

 

Just my opinion of course. I do tend to like really old school just for fun of course, in many things.

 

Doug 7rxc

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Since I own good discrete compasses, I don't need to buy the added feature of one on the GPS.

When you rotate a compass the needle swings around to point North. When you rotate a GPS with a magnetic sensor the needle swings around to point at the cache because the GPS knows its orientation with the respect to the earth's magnetic field and the bearing to the cache.
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Well that's how an electronic compass works, but we're no nearer knowing any real benefit ... I only have to walk a few steps and my Etrex also points at the cache. And as grasscatcher stated "you can't find a geocache while you're standing still" :)

 

Spot on! (that's one of those UK sayings, right?) :)

 

I remember when I got a 60csx. Finally, a GPS with electronic compass! After fiddling with it for an hour or two I disabled that function. Have not turned it back on since.

 

We have a lot in common. I learned how to use a GPS without an E-compass function and how to drive in stick shift car. :)

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Well that's how an electronic compass works, but we're no nearer knowing any real benefit ... I only have to walk a few steps and my Etrex also points at the cache. And as grasscatcher stated "you can't find a geocache while you're standing still" :)

 

Please read my above posts.....I really can't explain it any clearer.

If you prefer a manual transmission I can tell you you're in a big time minority however since I assume you've driven an automatic its still a valid opinion.

To continue to post opinions on something you've never used or experienced is simply not productive or informative.

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A number of the above posts demonstrate a point I tried to make......people confuse several issues.

 

I'll agree that things can get confusing because even on a GPS that DOESN'T have a compass, one of the pages is called a "compass" page.

 

People interchange the "pointer" with "compass". They are NOT the same.

 

I turn the "actual" compass off and strictly use the pointer (set on "bearing"). I hunt Benchmarks, and in rough terrain (the only kind there is where I hunt and hike), I'll establish a direction line following the pointer which is pointing to the specific coordinates I'm "going to". When I'm getting close to GZ, I'll drag one of my hiking poles and make a line in the dirt (or on rock) until the pointer swings around and essentially tells me "Hey Dummy, you passed it". Then I'll circle a little bit and come at GZ from a different direction, doing the same thing. Sometimes I'll do it even again for verification.

 

From that point even a blind squirrel can find the acorn.....X marks the spot!

 

That X was established without regard to cardinal direction, without magnetic interference from clothing, pocket contents, calibration,etc,etc.

 

When you turn the compass on and try to do the same thing, you will find that you have introduced multiple sources of possible variation.

 

Oh yeah, I've got four GPSs.....all with E Compasses. Three with 3 axis and one with 2 axis. Why, after my above opinions? Simple....to not have to carry additional equipment. If I need to determine the direction, I turn the compass on, calibrate it, use it as a compass, and turn it (and any possible source of error) back off.

Edited by Grasscatcher
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Please read my above posts.....I really can't explain it any clearer.

If you prefer a manual transmission I can tell you you're in a big time minority however since I assume you've driven an automatic its still a valid opinion.

To continue to post opinions on something you've never used or experienced is simply not productive or informative.

 

Manual transmissions are more popular in the UK than the US :)

 

Please note that I'm not trying to post an opinion on something I haven't used, I'm trying to establish what the big deal is so I can judge whether it's indeed worthwhile. I note your comment that it is useful when you can hardly move, but I can't recall ever being in that situation. I suspect the majority of cachers won't be either. If that really is the only advantage then there is little point in me, and I suspect many others, spending additional money simply to get a 3 axis compass.

Edited by sussamb
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Well that's how an electronic compass works, but we're no nearer knowing any real benefit ... I only have to walk a few steps and my Etrex also points at the cache. And as grasscatcher stated "you can't find a geocache while you're standing still" :)

I was pointing out the benefit of GPS with the a magnetic sensor over a compass. I have no problem with you walking and guessing which way the GPS thinks you are walking and then pointing the GPS that direction. The GPS uses two points that could be 30 feet off to determine direction, though. That is very inaccurate for me. I used to use a bearing compass and GPS bearing value for better accuracy, but when I got a GPS with a magnetic sensor that is accurate to a degree or so, I don't use the bearing compass anymore.
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also read my last post above

 

@ J E C,

??? What "two points that could be 30 ft off" are you talking about?

 

Surely not the "go to coordinates"....because even the e compass uses those for establishing its reference. You can never eliminate the possibility of those being in error....never!

 

That's why in my post above I mentioned hunting Benchmarks, while I failed to mention only those with adjusted coordinates. The procedure is the same, just that you might be zeroing in on an erroneous location with GC.

 

IMHO the bearing pointer is still the most accurate....for reasons mentioned above.

Edited by Grasscatcher
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Since I own good discrete compasses, I don't need to buy the added feature of one on the GPS.

When you rotate a compass the needle swings around to point North. When you rotate a GPS with a magnetic sensor the needle swings around to point at the cache because the GPS knows its orientation with the respect to the earth's magnetic field and the bearing to the cache.

Yep... and the GPS does the work of converting your current position and the position on the GOTO (cache) into a bearing to the cache from where you are. Non ecompass GPS use the 'compass page' to give a graphic indication of where you 'need' to go. That is relative to the heading you have been travelling. Same thing happens on the ecompass models. However the GPS switches between the 'compass page' and the ecompass display. The GPS can also display the digital information as well... distance and bearing and accuracy if you set it up that way.

 

Like I said, it's the same thing, maybe not so automated for sure, but I have to use a separate compass. Since I carry it anyway, might as well use it. To be honest it is mostly for resolving discrepencies or general orientation where the GPS doesn't work well.

 

BTW the compass page is much easier to read than the 'highway' or 'road' display for many.

Since the advent of ecompasses perhaps a better name for the 'compass page' would be in order, but some I've seen have both up at the same time. I don't have a problem with either way either.

Being able to recognize what one is looking at on the display and use it is a user responsibility and and is up to the individual. The OP was talking about odd readings on his ecompass, and we had one chap agreed he was turning himself into a 'magnet' through electrostatics... again a user fault. Liking one type of compass over another or only having one or the other isn't the problem being discussed, he was looking for ideas on what was happening.

 

Doug 7rxc

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@7XRC,

"Being able to recognize what one is looking at on the display and use it is a user responsibility and and is up to the individual."

 

You are absolutely correct......and the fastest way for the OP to have determined what the problem was would have been to turn the compass off and use strictly the bearing pointer. It would have lead him straight to the correct coordinate location.......then it would be a matter of figuring out what was causing the interference with his compass.

 

A VERY high percentage of GPS "errors" and "problems" are operator error......I'm not being personally critical.......it's just lack of experience,knowledge,understanding of what the unit is telling you and why. The more variables that can be eliminated until a higher level of proficiency is reached, the better.

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also read my last post above

 

@ J E C,

??? What "two points that could be 30 ft off" are you talking about?

 

Surely not the "go to coordinates"....because even the e compass uses those for establishing its reference. You can never eliminate the possibility of those being in error....never!

 

That's why in my post above I mentioned hunting Benchmarks, while I failed to mention only those with adjusted coordinates. The procedure is the same, just that you might be zeroing in on an erroneous location with GC.

 

IMHO the bearing pointer is still the most accurate....for reasons mentioned above.

I am curious. How do you think the GPS knows so accurately what direction you are walking?
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My first dedicated GPS was an Etrex30 with a faulty electronic compass. It was so frustrating and unreliable that I regularly resorted to switching it off and using the satellite based compass (i.e. the one that required you to move, at least I think that's what it did).

 

After that I bought a GPSMAP 62s and the compass is reliable. I use it all the time. When I'm looking for a cache I generally get to the approximate location, stop to look, refer to the gps for a direction in which it thinks I should walk, walk that way and check that the distance decreases. This works well with the current, accurate compass in pretty much all circumstances which I've encountered.

Most of my caching is in the countryside and often under trees where gps reception isn't great. If I'm relying on a gps based compass then presumably if neither the first reading used for the compass and the second reading for the compass are both inaccurate then the compass can't be trusted at all. I get to the approx. location and look at the compass. Walk in that direction. Now it tells me to walk in the other direction because the signals that it used for the compass were inaccurate. Now it tells me to walk in the other direction because those new signals were wrong... Or am I missing something in how they work?

 

One non-caching instance when I wouldn't have wanted to walk around to get a decent compass direction was in the mountains last year when we were close to white-out conditions and I knew that there some steep drops in the area. Of course, I also had a hand held compass and map but I find the gps much easier these days.

 

Having used both there's no way that I would now revert to a gps without an electronic compass

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Sticky Wicket.

I live in the USA, have been around a number of years, but never knew what the term actually referred to until I looked it up on Google yesterday.

 

I use the Delorme handheld gps devices for finding ground zero, but have followed the "sticky compass" threads about newer Garmin devices for hints and comparisons. The original poster on this thread outlined very well the manner in which his older Garmin device worked in the wide open Mojave desert. From his description, I inferred that automatic recalculation might not necessarily kick in until he had walked to within a 200 foot radius of the loaded cache coordinates.

 

Having now used several gps device models, functionally identical except for the electronic compass, I see no downside to having a device with an onboard magnetic/electronic compass feature that works properly at a standstill, even if I have to swing my arm around in public from time to time to calibrate it.

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also read my last post above

 

@ J E C,

??? What "two points that could be 30 ft off" are you talking about?

 

Surely not the "go to coordinates"....because even the e compass uses those for establishing its reference. You can never eliminate the possibility of those being in error....never!

 

That's why in my post above I mentioned hunting Benchmarks, while I failed to mention only those with adjusted coordinates. The procedure is the same, just that you might be zeroing in on an erroneous location with GC.

 

IMHO the bearing pointer is still the most accurate....for reasons mentioned above.

I am curious. How do you think the GPS knows so accurately what direction you are walking?

 

Totally mathematical calculations based on satellite location signal triangulation.

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My first dedicated GPS was an Etrex30 with a faulty electronic compass. It was so frustrating and unreliable that I regularly resorted to switching it off and using the satellite based compass (i.e. the one that required you to move, at least I think that's what it did).

 

After that I bought a GPSMAP 62s and the compass is reliable. I use it all the time. When I'm looking for a cache I generally get to the approximate location, stop to look, refer to the gps for a direction in which it thinks I should walk, walk that way and check that the distance decreases. This works well with the current, accurate compass in pretty much all circumstances which I've encountered.

Most of my caching is in the countryside and often under trees where gps reception isn't great. If I'm relying on a gps based compass then presumably if neither the first reading used for the compass and the second reading for the compass are both inaccurate then the compass can't be trusted at all. I get to the approx. location and look at the compass. Walk in that direction. Now it tells me to walk in the other direction because the signals that it used for the compass were inaccurate. Now it tells me to walk in the other direction because those new signals were wrong... Or am I missing something in how they work?

 

One non-caching instance when I wouldn't have wanted to walk around to get a decent compass direction was in the mountains last year when we were close to white-out conditions and I knew that there some steep drops in the area. Of course, I also had a hand held compass and map but I find the gps much easier these days.

 

 

Having used both there's no way that I would now revert to a gps without an electronic compass

 

The compass pointer becomes a " pointer to the cache" when a cache is loaded as a go-to. Once at GZ it is normal for the pointer to adjust a bit from time to time and you can expand the search area accordingly. A 62S should have little trouble under tree cover...the only place I've lost a signal was in a volcano crack in Mono Lake, CA, I could only see a couple feet of sky....when the crack opened I had a lock.

I stopped upgrading firmware at 3.90 when everything worked perfect. I bought another one and was running 4.60 I believe but found the 3.90 better and put it on the new one as well.

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Sticky Wicket.

I live in the USA, have been around a number of years, but never knew what the term actually referred to until I looked it up on Google yesterday.

 

I use the Delorme handheld gps devices for finding ground zero, but have followed the "sticky compass" threads about newer Garmin devices for hints and comparisons. The original poster on this thread outlined very well the manner in which his older Garmin device worked in the wide open Mojave desert. From his description, I inferred that automatic recalculation might not necessarily kick in until he had walked to within a 200 foot radius of the loaded cache coordinates.

 

Having now used several gps device models, functionally identical except for the electronic compass, I see no downside to having a device with an onboard magnetic/electronic compass feature that works properly at a standstill, even if I have to swing my arm around in public from time to time to calibrate it.

 

No need to swing arms for field calibration as for the CSx.....I've never needed to field calibrate a 62S or 450 ( I change batteries before each outing and at that time I check the compass and calibrate if necessary.)

Re the "sticky", it existed in almost all new Garmin models.....I know it was fixed with new firmware on the 62S and Oregon 450.

I've been in Mojave and other wide open areas and in those environments the accuracy of the 62S and 450 was scary ( good ).

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Re the "sticky", it existed in almost all new Garmin models.....I know it was fixed with new firmware on the 62S and Oregon 450.

For some reason the term, "Zone of indifference" popped out from my memory when thinking of the reported dead zone within 60 feet (radius or diameter?) of GZ reported by some Garmin 62S users before the firmware was modified. :)

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@ J E C,

??? What "two points that could be 30 ft off" are you talking about?

I am curious. How do you think the GPS knows so accurately what direction you are walking?

Totally mathematical calculations based on satellite location signal triangulation.

I think what JEC was getting at is that to do that calculation, it needs at least two data points to determine a direction. If one or both of those data points is inaccurate, like if you have spotty reception, that calculation can give an incorrect result. With a properly calibrated electronic compass, satellite reception has no effect on the heading the GPS will display.

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@ J E C,

??? What "two points that could be 30 ft off" are you talking about?

I am curious. How do you think the GPS knows so accurately what direction you are walking?

Totally mathematical calculations based on satellite location signal triangulation.

I think what JEC was getting at is that to do that calculation, it needs at least two data points to determine a direction. If one or both of those data points is inaccurate, like if you have spotty reception, that calculation can give an incorrect result. With a properly calibrated electronic compass, satellite reception has no effect on the heading the GPS will display.

Well, I think the more important point is that if you then stop, it continues pointing the same way according to how you were moving even if you turn and face another direction.

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Yes, you need at least two points and the GPS assumes you are walking in a straight line to get direction. If you look at a track zig-zagging down a straight path/road you can see how a the direction you are moving can be off.

 

There is feature on my 60csx where I can get a very accurate bearing using the gun sight on the bezel(white triangle just above the "p" in "GPSmap"). You turn until the arrow points at the triangle and then sight from the back sight(the up triangle on the big button) to the front sight on the bezel. Of course this only works with the magnetic sensor on. Turning does nothing when the electronic compass is off. The needle magically turns on the screen when you turn with the magnetic sensor on.

 

A lot of threads like this have the phrase the OP uses. "when I get near the cache". I like to think about it with the question. "what is the bearing when I am standing on the cache?" It turns out that if you are within the 30 foot circle around the cache, the answer is the same. The bearing can be any direction. The farther you walk away from the cache the more accurate the bearing will be.

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@ J E C,

??? What "two points that could be 30 ft off" are you talking about?

I am curious. How do you think the GPS knows so accurately what direction you are walking?

Totally mathematical calculations based on satellite location signal triangulation.

I think what JEC was getting at is that to do that calculation, it needs at least two data points to determine a direction. If one or both of those data points is inaccurate, like if you have spotty reception, that calculation can give an incorrect result. With a properly calibrated electronic compass, satellite reception has no effect on the heading the GPS will display.

 

Actually, the direction that the needle points is based on where it thinks you are standing in relationship to the target. If because of bad coverage, multi-path, etc, it thinks you are standing in a spot different than where you actually are, it can point in the wrong direction. This would be exaggerated the closer you are to your target.

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@ Don J,

 

Thank you for injecting actual common sense reasoning and actual facts ......that is refreshing!

 

Your explanation is why, that when I am hunting "accurate, adjusted location Benchmarks" with my compass turned off, I still try to approach GZ from several different directions, just to try and verify that my unit is "telling" me the truth and that "IT" truly understands where it is and can "repeat" (with itself).

 

I have examples of waypoints that were marked simultaneously ,at exactly the same point by multiple GPS units on a very narrow single track trail, NONE of which accurately describe the actual spot. All three are incorrect and it's surprising how far "away" "They thought they were". (100+ ft and all different)

All due to multipath error....

 

By elimination of the multipath, I since have been able to get the correct trail location as well as "spot" location.(and can "repeat".

 

The user must be able to recognize when the unit "may" be lying and what changes in settings or procedures possibly need to be made to correct for those errors......that's why I referred to "thinking persons tool".

Edited by Grasscatcher
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I'm the OP.

 

None of the replies were particularly helpful.

 

In 3 years, I've never before had this happen. I should be able to start walking in the direction of the pointer and, if I'm walking in a strength line, come somewhat close to GZ. It has alawys been like this in the desert. Here the straight line would have put me 100 to 150 feet off.

 

I'm ok with the idea that when I get close, the arrow does not help much. But, I should not have been walking giant "J" shapes in the open desert.

Now, any good explanations?

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