Why are the electronic compasses so bad?

[+Goldom & Gardenia]

From what I hear my experience is not unique - that the compass on GPSrs are generally pretty poor. I have a Vista HCx and this is quite true. The compass is frequently way way off what a real compass shows (yes, it's set to magnetic north), and is often so worthless as to not vary the supposed direction I'm facing by more than about 25 degrees even when I turn a full circle. I try recalibrating it but it doesn't really help much. Why is it so hard to make an electronic compass actually work, and is there anything I can do to improve its accuracy? I generally have to just turn off the compass and briefly jog around to get the speed up enough to get a real heading from the GPS instead of the compass.

 

Also, should I be holding it like a real compass (flat) or vertical as the GPSr is normally held?

Edited December 17, 2007 by Goldom & Gardenia

[+TrailGators]

From what I hear my experience is not unique - that the compass on GPSrs are generally pretty poor. I have a Vista HCx and this is quite true. The compass is frequently way way off what a real compass shows (yes, it's set to magnetic north), and is often so worthless as to not vary the supposed direction I'm facing by more than about 25 degrees even when I turn a full circle. I try recalibrating it but it doesn't really help much. Why is it so hard to make an electronic compass actually work, and is there anything I can do to improve its accuracy?

The compass is effected by signal strength and signal bounce. You can turn off the compass when it is acting erratically. Then when you walk in a straight line you should be able to get a decent bearing as long as you aren't under trees. Edited December 17, 2007 by TrailGators

[+MikesTooLz]

The only electronic compass that I have use was the one on my digital watch. For the most part it is always dead on.

[+W7WT]

I was very unhappy with the compass on my Vista HCx until I started holding it horizontal and now it is working very well. Yes the HCx has a patch antenna and works best when held horizontal. I also have the 76C and 76S with the Quad Helix which worked best held vertical. I had a hard time holding the HCx horizontal. Good luck Dick, W7WT

[+pigpen4x4]

I feel the E/C is for pointing to the waypoint, and little else.

And mine (both a 60CSx and a Vista HCx) do this quite well.

When I need a compass I pull one out.

Interstingly, early on, I went deep into a very hilly forest off a trail without marking a waypoint. I knew only that I was heading west using my original Vista, but following it back east with the E/C, I got right back to the main trail. Now, I HOPE I know better.

[+Prime Suspect]

From what I hear my experience is not unique - that the compass on GPSrs are generally pretty poor. I have a Vista HCx and this is quite true. The compass is frequently way way off what a real compass shows (yes, it's set to magnetic north), and is often so worthless as to not vary the supposed direction I'm facing by more than about 25 degrees even when I turn a full circle. I try recalibrating it but it doesn't really help much. Why is it so hard to make an electronic compass actually work, and is there anything I can do to improve its accuracy? I generally have to just turn off the compass and briefly jog around to get the speed up enough to get a real heading from the GPS instead of the compass.

 

Also, should I be holding it like a real compass (flat) or vertical as the GPSr is normally held?

Electronic compasses can a do work just as well as a magnetic compass. The problem, in virtually every case I've seen, is user error. The last line in your message bears this out. Had you read the user manual, you would have seen that you need to hold the unit horizontally. Also, there is an on-screen error message that displays when you're not holding the unit flat (did you never wonder why that was showing up?). You WILL get erroneous readings if you don't hold it flat.

[+Prime Suspect]

The compass is effected by signal strength and signal bounce.

Huh? This unit has a true electronic compass. It detects the magnetic lines of force. It doesn't pick up signals.

[+kenk]

Since I got my first GPS I was firmly entrenched in the philosophy that electronic compasses on GPS's were entirely unneeded and not worth the price added.

 

Besides, I have lots of very good magnetic compasses and am very experienced at use of maps and compass together. Why in heck would I need an electronic compass.

 

And then I got my GPSMAP 60CSx - with the electronic compass.

 

Now my view has changed 180 degrees!!!

 

The ability to stand still and have the compass waypoint pointer point exactly (almost?) at the waypoint is absolutely AMAZING!!!

 

I will never again get a GPS without the electronic compass.

 

Oh, and yes, the GPS does need to be held horizontally for it to work accurately. I've also found it best to recalibrate the compass fairly often, but that is very very easy to do.

Edited December 17, 2007 by kenk

[GeoBobC]

After living without a magnetic compass in a GPS for many years, I took the plunge and bought a 60CSx to complement my 60Cx. I could never get the magnetic compass to provide consistently accurate readings, and even after calibration and carefully holding it, it would read between 2 and 8 degrees off from my hand-bearing compass that I've relied on for many years. It's useful for getting a general sense of what direction is what while stationary, but not nearly as accurate as a hand held compass in my testing. I was so disappointed that I took the unit back and exchanged it for another 60Cx. That's my opinion. I wondered the same thing: why can't they make these compasses more reliable? I don't need to baby my other non-GPS compasses to get accurate readings so I'm not sure what's up.

[gallet]

 

...that the compass on GPSrs are generally pretty poor ...

 

Also, should I be holding it like a real compass (flat) or vertical as the GPSr is normally held?

 

You ask why it's so hard to make a compass that works then you ask for instructions on how to use it!

 

I have checked out the electronic compass on about half a dozen HCx's and 60CSx's and they all have worked just as they are supposed to. Generally when checked against a Silva compass I've found the fluxgate compasses to be within a few degrees of the Silva. Perfectly adequate for the job it is meant to do.

[+Klemmer]

I'm very happy with the electronic compass in my Magellan Meridian Platinum. Assuming I remember to hold it in the hand that the watch is NOT on, and that there are no other metalic item nearby (like the jeep, underground pipes, sidewalks with rebar, etc), I find it is very accurate. It is a 3-axis stabilized type, so it works well no matter how I hold it. I don't belive the Garmin ones are 3-axis stabilized. Magellan has taken a lot of hits lately (mostly they sound deserved, especially re customer service), but they did a very good job on the Meridian series. I believe it was designed before they got bought by (and later got away from) Thales.

[+Goldom & Gardenia]

Electronic compasses can a do work just as well as a magnetic compass. The problem, in virtually every case I've seen, is user error. The last line in your message bears this out. Had you read the user manual, you would have seen that you need to hold the unit horizontally. Also, there is an on-screen error message that displays when you're not holding the unit flat (did you never wonder why that was showing up?). You WILL get erroneous readings if you don't hold it flat.

 

Not sure what you mean, I've never gotten an error message no matter what I do. Doesn't say anything about it in the manual either, at least not on the page about using the compass. I'll try it flat though. Calibration also doesn't seem to work right which may be part of the problem - it says to do 2 full turns, but doing just 2 doesn't finish it at all, the progress bar is only about half full at that point and just sits there unless I keep spinning 5-6 times.

Edited December 17, 2007 by Goldom & Gardenia

[+coggins]

Electronic compasses can a do work just as well as a magnetic compass. The problem, in virtually every case I've seen, is user error. The last line in your message bears this out. Had you read the user manual, you would have seen that you need to hold the unit horizontally. Also, there is an on-screen error message that displays when you're not holding the unit flat (did you never wonder why that was showing up?). You WILL get erroneous readings if you don't hold it flat.

 

Not sure what you mean, I've never gotten an error message no matter what I do. Doesn't say anything about it in the manual either, at least not on the page about using the compass. I'll try it flat though. Calibration also doesn't seem to work right which may be part of the problem - it says to do 2 full turns, but doing just 2 doesn't finish it at all, the progress bar is only about half full at that point and just sits there unless I keep spinning 5-6 times.

 

Looking at the manual and a little history...

 

From the original Vista Manual (page 18):

2. Hold the eTrex Vista level to get an accurate Elec-

tronic compass reading.

 

A 'Hold Level' reminder displays if you are not hold-

ing the Compass correctly, or if it is not calibrated.

http://www.garmin.com/manuals/eTrexVista_OwnersManual.pdf

 

 

The manual that comes with the Vista HCx says the following (page 28):

 

2. Hold the eTrex Vista level to get an accurate

electronic compass reading.

http://www.garmin.com/manuals/eTrexLegendH...wnersManual.pdf

 

Might just have gotten rid of that message, as they tell you to hold it level in the HCx manual.

Edited December 17, 2007 by coggins

[Hertzog]

I'm very happy with the electronic compass in my Magellan Meridian Platinum.

I think the 3-axis compass is the one place we all agree that the Magellans trump the Garmins.

 

I'm curious about the calibration of the Magellan compass; we talk a great deal about the calibration procedure for the Garmins, but I've never heard anything about the Magellans. Do they have a similar two turn procedure? And is there an additional requirement to rotate it about its "roll" axis?

[+hogrod]

I'll try it flat though. Calibration also doesn't seem to work right which may be part of the problem - it says to do 2 full turns, but doing just 2 doesn't finish it at all, the progress bar is only about half full at that point and just sits there unless I keep spinning 5-6 times.

 

No don't try it flat, use it every time flat or it won't work.... this is a non issue since this is how the patch antenna in the etrex series whats you to hold the unit anyway(also the most comfortable way to use it).

 

When calibrating the compass make sure to hold the unit flat. You are turning to fast if you are spinning 5-6times. Turn slowly just like the gps says on the calibration screen (I just turn the unit in my hands, no reason to spin in circles). mine is always calibrated after 2-3turns.

[+pigpen4x4]

Goldom & Gardenia,

Your last post made me wonder if the E/C is turned on?

I have not dug real deep into my Vista HCx, but on my 60CSx, it can be turned off in the menus.

Good Luck!

PP

[+Klemmer]

Hertzog:

Yes, the Magellan has a calibration procedure (2 different ones). The "normal" one in the two-turn variety. It works well. It needs to be flat, no metal around. There is an arrow you keep pointing at you by turning the unit. Simple enough. Then you flip it over until it beeps at you. I do it maybe once every 2 or 3 months, when I think of it. NO need to do it every time you change batteries (which I heard once from a 60CS owner). That seems excessive to me.

 

There is also a "major" recalibration procedure, for when you really mess it up (leave it next to a magnet), or do a factory re-set, or leave it without good batteries in it for a long time (weeks?). I've only had to do it maybe twice in 3+ years. The software guides you to set it (or hold it) on each edge and side, one by one, then the normal two turn deal. I suspect that the first part (edges) may be more of a calibration of the 3-axis stabilizer system.

 

Oh, every once in a while (couple times per year), it gets "stuck" or something (not working - pretty obvious), and you just have to turn the compass off (a menu item), then turn it on again. That "resets" it.

 

Once in a while Magellan does something right. Delorme should look at it for their next unit, and Garmin should also. I have heard (and seen here) lots of issues with Garmin's implementation, but I don't own a Garmin e-compass unit, so I can't compare directly.

Edited December 17, 2007 by Klemmer & TeddyBearMama

[+Cacheoholic]

I’ve owned several Magellan units with 3-axis electronic compasses (Meridian Platinums and eXplorists 600) and also several Garmin units with 2-axis electronic compasses (60CS, 60CSx and Vista HCx).

 

The Magellan 3-axis electronic compasses are wonderful. I always had the electronic compass turned on and never really needed to recalibrate it. I just did it every once in a while to amuse myself.

 

The Garmin 2-axis electronic compasses, IMO, are crap in comparison. They only work if you keep them constantly calibrated and hold them perfectly level. I seldom ever have it turned on. I had hoped Garmin would wake up and include a 3-axis electronic compass in their new Colorado line but it doesn’t sound promising.

[TomOfTarsus]

The Garmin 2-axis electronic compasses, IMO, are crap in comparison. They only work if you keep them constantly calibrated and hold them perfectly level. I seldom ever have it turned on. I had hoped Garmin would wake up and include a 3-axis electronic compass in their new Colorado line but it doesn’t sound promising.

(Emphasis mine)

 

That's my rub. It seems from floating around here for a couple of weeks thinking and learning and trying to decide, that even if the technology is available, they either can't or won't put it in 1 package. "Can't" I can understand, "won't" I don't get at all, but I obviously don't know which it is.

 

The Colorado looks promising enough to wait for it, or even (hopefully) a Rino-like radio version. And I'd always take my Silva anyway, but sheesh! Here's your front line handheld unit and you use a second-rate compass...

 

Either their marketing department is screaming in agony or they've got some cockeyed "incremental" plan to keep people buying and hoping...

 

But it's Christmas, so I'll stop being grumpy! Merry Christmas to all if I don't get back on here!

 

Tom

 

(who can never get it right the first time...)

Edited December 18, 2007 by TomOfTarsus

[QuigleyJones]

I've never had much of a problem with mine (60csx), I rarely calibrate it generally only if it seems a bit wonky and afterwards it always points north.

Then again I don't use it that much. And I can see having to hold it level get tedious quick. As theres not much difference between the astro and 60 maybe one should get the astro?

[Hertzog]

Hertzog:

Yes, the Magellan has a calibration procedure (2 different ones) ...

Thanks for the info; I've been curious about that. It's pretty much like I expected -- you have to "roll" it in some fashion in order to calibrate the 3rd sensor. Although it's more complicated than the Garmin procedure, I wouldn't mind the extra work to get a decent 3-axis compass.

[+GOT GPS?]

I wished I still had the Magellan Meridian Platinum, because it had the best compass of any GPS I ever had, even seemed to work better than the compass in the SporTrak Color, that I had.

[+Klemmer]

Yeah, if my MeriPlat breaks beyond economic repair, I may have to haunt Ebay for a used one. Also love the almost unlimited number of waypoints (for benchmark hunting) with the capability to save waypoint files to the SD card.

Now, for Christmas, if Santa could magically merge the best of the MeriPlat and my Delorme PN-20....... Merry Christmas to all!

[xxgg]

Now...

 

Some of you are using a actual seperate compass.

 

Which brand/model compass do you use (primary) ?

 

Web link (pic) would be nice.

[GeoBobC]

I've used a Suunto KB-14 hand bearing compass for many years. It is extremely accurate and provides readings within 1/2 degree.

 

http://www.thecompassstore.com/51kb14360rd.html

[+kenk]

Which brand/model compass do you use (primary) ?

 

For a magnetic compass I recommend a plastic baseplate compass with adjustable magnetic declination.

 

Probably the best deal in a compass right now is the Suunto M-3 Leader without the Global Needle for $20. http://www.forestry-suppliers.com/product_...age.asp?mi=1283

 

The Brunton 9020G is a great small compass for stuffing in a pocket. I even carry one when going to places like Disney World or similar. http://www.forestry-suppliers.com/product_...age.asp?mi=7091

 

For a bit higher bearing accuracy my favorite mirrored compass is the Brunton 15DTCL, which is the original so-called "ranger-style" compass designed by Silva of Sweden. The other thing I like about the 15DTCL is that it has a built-in UTM grid for transfering UTM coordinates from the GPS to topo maps, and vise versa.

http://www.forestry-suppliers.com/product_...age.asp?mi=7088

 

BTW, Silva SE owns Brunton ... a compass sold in the US with the Silva label is NOT a real Silva of Sweden compass.

 

Brunton's "Eclipse" compasses (8099, 8097, 8096) are also real nice, but they tend to be a bit more expensive than some other alternatives. Their magnified displays are great for those of us with "aging" eyes.

Edited December 19, 2007 by kenk

[+GClouse]

I have a standalone electronic compass, and it has always been fairly accurate. It does have to be calibrated when moved over 100 miles with it powered off. calibration involves setting the calibration mode, holding it level and pressing a button, then turning it 180 degrees, holding it level again and pushing the button again.

 

My car also has a built-in electronic compass, but it only displays N W S E and not degrees. The calibration for the car is silly-looking, because you have to put it into calibration mode and drive the car in a circle until the thing chimes at you. This takes from 3 to a dozen circles.