Colorado location errors

[+twolpert]

As an aside: out of 6 test runs with my new Colorado on 2.7 I've seen 3 drifts, one over 350', so for me the issue has not been addressed in the newest hardware or software. If anything it feels worse than my old unit.

That's disappointing. I was hoping that this would turn out to be an interaction between bad firmware and some unit-specific hardware variation. But since it also occurs with your replacement unit, it's probably not unit-specific. So we're all at risk.

[+Gob-ler]

I have been caching hard since the 2.70 upgrade and have not had any location errors. I have also noticed that the accuracy seems to be quite a bit more stable. I think they have done something cause it is working a lot better than it was.

 

One thing I have noticed that I did not have before is a hesitation or lag when bringing up the cache information page and then going to logs or hints. Sometimes it is several seconds or more.

[+g-o-cashers]

I have also noticed the slowness in bringing up cache descriptions, especially on caches with long descriptions. This seemed to happen when Garmin fixed the garbled text issue on both the OR and CO in the most recent release on both units.

 

GO$Rs

[+Crid]

Having done several woodland walks with 2.70, it does seem to be better. Apart from one instance of 100ft+ EPE for no reason (and no similar deviation in the same area on the return journey 10 minutes later), it's looking good so far. The cynic in me wonders if it's because there's less leaf canopy at this time of year, but so far (touch wood) I've not had any big drifts.

 

Murphy's Law says it'll probably do it now.

[+Gob-ler]

I have cached hard the last two weeks in the Buffalo Area and have not had one location error. Heavy tree cover was no problem and being in the Niagara Gorge was not a problem.

 

The hesitation in bringing up descriptions is still quite noticeable and I am also seeing a longer than normal delay updating while using CN9NT, actually a much longer than normal delay.

[+g-o-cashers]

I lost a bunch of my data from a few weeks ago but I'm beginning to think that my failures are caused by high PDOP and heavy cover. Even though the 60csx and Oregon as accurate as they normally would be during these same walks it seems to affect the Colorado much more. I notice that the PDOP during the times of day I walk (it doesn't change much over the course of several weeks) has been pretty high. That combined with a lot of rain (wet, full leaves) I'm guessing is having the negative effect on my Colorado. That said I've still seen location errors on my Colorado with low PDOP as well, but it is always under heavy cover.

 

As Crid said though, in a few weeks the leaves will be gone -- I'm guessing for those of us in the northern hemisphere the problem will magically fix itself for a few months or at least be a lot less frequent.

 

GO$Rs

[+StarBrand]

Now that my Colorado has started experiencing the more serious "drift" issues - I have contacted tech support and today received the following:

 

We have been able to reproduce the issue and are working closely with our vendor to remedy the situation. At this point, customers will see no benefit by returning/exchaging units as the cause does not appear to be hardware related defects. Nearly all units may see this issue under some circumstances. We cannot provide a timeline for when we anticipate resolution but please know we are working very hard to resolve this problem quickly.

 

I will wait.......

[SiliconFiend]

Now that my Colorado has started experiencing the more serious "drift" issues - I have contacted tech support and today received the following:

 

We have been able to reproduce the issue and are working closely with our vendor to remedy the situation. At this point, customers will see no benefit by returning/exchaging units as the cause does not appear to be hardware related defects. Nearly all units may see this issue under some circumstances. We cannot provide a timeline for when we anticipate resolution but please know we are working very hard to resolve this problem quickly.

 

I will wait.......

Wow, that's HUGE progress! They've actually recognized and admitted to a problem! Here's hope for us Vista HCx owners, too (although I've had reasonable success with 2.70/2.30).

[+Tequila]

Now that my Colorado has started experiencing the more serious "drift" issues - I have contacted tech support and today received the following:

 

We have been able to reproduce the issue and are working closely with our vendor to remedy the situation. At this point, customers will see no benefit by returning/exchaging units as the cause does not appear to be hardware related defects. Nearly all units may see this issue under some circumstances. We cannot provide a timeline for when we anticipate resolution but please know we are working very hard to resolve this problem quickly.

 

I will wait.......

 

Since it is not hardware related, I assume it is software/firmware. So what do they mean "working with our vendor"? Does Garmin outsource their software development??

[+g-o-cashers]

Since it is not hardware related, I assume it is software/firmware. So what do they mean "working with our vendor"? Does Garmin outsource their software development??

 

I'm guessing the GPS firmware is probably provided by the GPS vendor. Garmin probably writes their application software to a specified GPS API and requires the hardware vendor to conform to it with their firmware (running on top of their hardware).

 

This is good news, hopefully Garmin will be able resolve this long standing issue.

 

GO$Rs

Edited October 6, 2008 by g-o-cashers

[+Crid]

Now that my Colorado has started experiencing the more serious "drift" issues - I have contacted tech support and today received the following:

 

We have been able to reproduce the issue and are working closely with our vendor to remedy the situation. At this point, customers will see no benefit by returning/exchaging units as the cause does not appear to be hardware related defects. Nearly all units may see this issue under some circumstances. We cannot provide a timeline for when we anticipate resolution but please know we are working very hard to resolve this problem quickly.

 

I will wait.......

Wow, that's HUGE progress! They've actually recognized and admitted to a problem! Here's hope for us Vista HCx owners, too (although I've had reasonable success with 2.70/2.30).

Yeah, until the next person contacts Garmin tech support and is told they've never heard of the problem. I fear we've been down this road before. Rinse, wash, repeat.

[+Tequila]

I would hope that Garmin is sincere about finding a solution. I imagine the mounting number of returns is a significant incentive. And that response seems reasonably well crafted. I doubt some front line support rep made that up. However, that is not to say everyone got a "bulletin" on how to respond when they take a call on "drift".

 

This is the third time I have heard about Garmin's intent to address this issue. They replaced my CO twice before giving up and sending me an Oregon instead. In my conversations with them, the support rep orally admitted they know there is a problem and were trying to isolate it. He was very keen to get one of my units back to study it.

 

Another friend was told a similar story.

 

So let's hope the fix comes out soon.

 

BTW, my friend was also told that Garmin is re-designing the back cover to address the waterproof issues. Not sure if that is cast in stone.

Edited October 7, 2008 by Tequila

[+tmitchh]

I just received an Oregon as a replacement to my CO having horrible drift issues. It was my fourth return in six months.

 

I would hope that Garmin is sincere about finding a solution. I imagine the mounting number of returns is a significant incentive. And that response seems reasonably well crafted. I doubt some front line support rep made that up. However, that is not to say everyone got a "bulletin" on how to respond when they take a call on "drift".

 

This is the third time I have heard about Garmin's intent to address this issue. They replaced my CO twice before giving up and sending me an Oregon instead. In my conversations with them, the support rep orally admitted they know there is a problem and were trying to isolate it. He was very keen to get one of my units back to study it.

 

Another friend was told a similar story.

 

So let's hope the fix comes out soon.

 

BTW, my friend was also told that Garmin is re-designing the back cover to address the waterproof issues. Not sure if that is cast in stone.

[+Crid]

Well so far (touch wood) 2.7 on the Colorado hasn't given me any drift issues. In fact, in a recent woodland mapping expedition with two GPSRs, there was one point where the Colorado was doing much better than my 76CSx. A 90 degree turn was involved and the 76CSx took a while to get on track after the turn (it was a fair way off to the side I had entered from for a couple of minutes). I think it's an averging thing, and I did upgrade the 76CSx whenever the last firmware update was released (probably a few months ago now, but I'm pretty sure I'd had the Colorado for a few months by then).

 

As I've said previously, it may just be due to the reduced leaf canopy at this time of year. But right now I'm actually starting to gain confidence in the Colorado's ability to get me to the right spot in a forest.

Edited October 11, 2008 by Crid

[+Red90]

It appears a new GPS Chipset firmware is out today.

[+Timpat]

It appears a new GPS Chipset firmware is out today.

Ok, who's going to be brave and update to this version 2.80 first and report back?

[balga]

Update worked see:

 

http://forums.Groundspeak.com/GC/index.php?showtopic=205915

 

Colorado 300 is still working.

[+g-o-cashers]

Upgrade completed. Now I want to go try it. Hmmm, I wonder if the dog wants to go for a walk?

 

Hopeful this addresses the drift issue.

 

GO$Rs

[+g-o-cashers]

After upgrading to 2.8 I let the Colorado sit outside to build the almanac and noticed several things:

 

- After being outside for about 20-30 minutes the position and EPE looked normal but the altitude was about 200' too high

- After being outside for about 40-50 minutes the position and EPE still looked good but the altitude was about 150' too low

- I moved the GPS to have a better view (although it already had 8-9 satellites and EPE was 11'-12') and the altitude moved to within 40'-50' of what I would expect

- I turned on WAAS and about 5 minutes later satellite 51 locked, my EPE went to 8' with 11 satellites and my altitude got to within 20'

- I power cycled the unit several times and the unit had lock by the time map page showed up, but WAAS wasn't working. For some reason instead of locking on 51 it is trying to lock on 33 which either doesn't work or is taking a very long time (> 20 minutes). If I disable/enable WAAS the unit goes back to 51 immediately and gains WAAS lock very quickly.

 

I'd be curious what other people are observing with respect to GPS altitude and WAAS if you've updated to GPS 2.8.

 

GO$Rs

[+Red90]

Just checked. Mine WAASed to 51 on first power up and then to 48 on the second. Both lock and hold fine even in the middle of my house. Altitude is fine and within what I would expect with the EPE.

 

As you, warm start is before it gets through the startup screens.

 

First impression is the position accuracy inside my house is better than normal.

[+g-o-cashers]

My finally WAAS'ed to 43. I'm not sure how long it took but it was less than 30 minutes but more than 10!

 

I don't remember this behavior with the 2.6 firmware, I seem to remember getting 51 all the time. The Oregon has a similar problem, hopefully the Colorado didn't pick up the OR's bad WAAS habits.

 

Over the last 30-40 minutes GPS altitude seems to be back within normal range, hopefully the original readings were just a fluke.

 

Tomorrow morning I'll take it over the test course to see how it does.

 

GO$Rs

[+Timpat]

My 300 seems fine after the update to 2.80. I did have to cycle WAAS Off/On once to get it going, but I saw this after the last firmware update, too. After gathering a new almanac it got diff corrections (Ds) as it should. I'm in a similar geographic location as g-o-cashers and upon turning my 300 Off then On it goes thru its WAAS search routine starting on 33 for about one minute, before realizing it's not in my sky, and moves to 48 or 51 in my case, and locks on to WAAS after about one more minute. Tonight it's using 48. Elevation for my home location is fine, too. Start up acquisition is very quick as well. So far all looks great. Will have a chance tomorrow morning to field test a bit.

[+GeekBoy.from.Illinois]

I'd be curious what other people are observing with respect to GPS altitude and WAAS if you've updated to GPS 2.8.

 

I loaded firmware ver 2.80 tonight after I finished a few things I needed to do on-line. After loading, I turned the GPSr on in the house and had 3 satellites locked while still inside. I walked out on my front walk and within 2 minutes, I had 6 satellites locked, 3 more "negotiating" and I even had a solid lock on #51 with a WAAS lock. I usually need 5-10 minutes to get the WAAS lock, but not tonight (and teh GPSr had been off for over 4 hours).

 

I didn't seen anything out of the ordinary for my position or elevation. I normally get a reading of ~803 feet for my elevation, and I was seeing 797 tonight. That is only off my 6 feet or about 0.1% (I think). I will see better in the morning on my drive to work. I have been seeing EPE in the 8-9 feet range while driving 45-50 MPH down the road on my way to work, so I would be real surprised to see EPE better than that... I should mention that my drive to work is through fr suburban/fringe farming areas, so I generally have a good view of the sky and can often get a nice spread of satellites.

[balga]

 

I'd be curious what other people are observing with respect to GPS altitude and WAAS if you've updated to GPS 2.8.

 

 

Started my Colorado 300 this morning

- the altitude is within the range I had before,

- WAAS I get within 2 Minutes (on satellite 33, already found after the update but I did not notice how long it took, dit not disable / enabled WAAS after update)

- EPE: nothing special

[+g-o-cashers]

I took my 400t on its first real test with GPS firmware 2.8 this morning. Same settings as usual along my normal test course:

 

* NiMH 2700mAh batteries, battery settings set to NiMH. Batteries were fresh.

* Tracklog: Capture every 3 seconds

* Backlight: Off

* Compass: Off

* WAAS: Off

* Maps: Topo 2008, City Nav NA NT 2009 loaded but disabled

* Software 2.7/GPS 2.8

 

The good news is that it performed very well. Here's the Colorado plot from this morning compared to the reference track -- this is about as good as it gets. Yellow is the reference track which is about 20' wide, blue is the CO track.

 

http://garmincolorado.wikispaces.com/file/...l/081015_CO.png

 

Things I noted:

 

- Lock this morning took about 40-50 seconds after having the unit off for about 8-9 hours. Pretty typical for the Colorado (but longer than the Oregon, I really notice the difference after using the Oregon)

- EPE started around 13' when I entered the woods and spent most of the time between 17'-20' while on the walk. This is normal when I have a "good" test.

- Most of the time I had 7 satellites

- Both the odometer and tracklog agreed on distance within 100' over a mile (2%). This is typical on the CO (and 60csx) for a good run

- GPS elevation seemed to be inline with the EPE I was observing

 

I still see weirdness with WAAS. Sometimes I get 51 and WAAS locks very quickly (30-60 seconds). This always seems to happen when I first enable WAAS. However after a power cycle the unit sometimes tries 51 and others 33. If it tries 33 the the lock sometimes happens but it takes 5-10 minutes and 33 is much harder for me to see so 33 will come and go as I move around.

 

Overall very good news since I was seeing the location errors in almost every test over the last few weeks. If I can see positive results over the next week I'll start to feel pretty good about this update and the fact that this issue might be finally resolved.

 

GO$Rs

Edited October 15, 2008 by g-o-cashers

[+StarBrand]

I took my Colorado 300 out with my Legend HCx and my Oregon 200. First I drove a 4 mile course around town. Second - I walked about 1.5 mile course. The Colorado track was as good as I have seen it on both trials. In fact it seemed better than the Oregon on a few turns near heavy tree cover.

 

I let it sit out in the open for a long while and did not see the constant jittery movements on the map that had become typical on my unit. Looks good - I think they may have solved the "drift"!!!

 

Took a very long time to get WAAS at first but seems all better this morning.

[balga]

 

I'd be curious what other people are observing with respect to GPS altitude and WAAS if you've updated to GPS 2.8.

 

 

Started my Colorado 300 this morning

- the altitude is within the range I had before,

- WAAS I get within 2 Minutes (on satellite 33, already found after the update but I did not notice how long it took, dit not disable / enabled WAAS after update)

- EPE: nothing special

 

Evening, same location: no WAAS at all (did not toggle WAAS off / on)

Next Morning: WAAS again (I checked 5 minutes after starting device, device off during night)

 

As I do not remember how well WAAS performed with the old chipset SW my observations are not very useful.

[+Crid]

I'm hoping they release a standalone version of this firmware soon, since I have no desire to install Web Updater.

Edited October 16, 2008 by Crid

[+SimbaJamey]

I just installed the 2.8 update and the unit seems to do things (menu pages, map draws) faster than it had been.

I have high hopes for this one...When I got my Co. in May it came with the 2.6 software and worked great right out of the box. Right before 2.7 came out I think I saw a location error once or twice but for the past month or so it's been happening constantly! And yes, I did 2.7 but it only seemed to make it worse. Now on a day when I go out for 3 caches, I have to power-cycle the unit usually for 2 of them because it gets to the point where I realize something's not right. After the power-cycle I usually end up about 200' from the cache and every time it turns out I walked right past it at some point but the Co. never said I got closer than about 100' before the power-cycle.

 

I had been looking here for a place to put this but it seems the Co. complaints have become fewer and farther between (Oddly, right about the time mine started having problems).

 

One new problem I've been having for a month or so is that my field-notes will no longer upload, the GC page kept telling me 0 records found. I finally figured it out this past Sunday, it's leaving the GC off the beginning of the cache ID. When I put it there and saved the file it worked exactly how it's supposed to. Anyone else having this issue?

 

And lastly, although this one hasn't happened in a while (maybe since 2.7?)...I'm pretty sure it would happen when I was switching profiles between automotive and recreational (Pretty much the only 2 I ever use) that the Co. would CONSTANTLY switch it's self from Track Up to North Up.

 

 

[kafkar]

I just installed the 2.8 update and the unit seems to do things (menu pages, map draws) faster than it had been.

I have high hopes for this one...When I got my Co. in May it came with the 2.6 software and worked great right out of the box. Right before 2.7 came out I think I saw a location error once or twice but for the past month or so it's been happening constantly! And yes, I did 2.7 but it only seemed to make it worse. Now on a day when I go out for 3 caches, I have to power-cycle the unit usually for 2 of them because it gets to the point where I realize something's not right. After the power-cycle I usually end up about 200' from the cache and every time it turns out I walked right past it at some point but the Co. never said I got closer than about 100' before the power-cycle.

 

It seems to be placebo effect that CO is faster after upgrading of GPS chip firmware to 2.8. .. GPS Unit firmware is still 2.7 as far as I know ..

[+StarBrand]

I'm hoping they release a standalone version of this firmware soon, since I have no desire to install Web Updater.

Why??

[+g-o-cashers]

I just installed the 2.8 update and the unit seems to do things (menu pages, map draws)

 

One new problem I've been having for a month or so is that my field-notes will no longer upload, the GC page kept telling me 0 records found. I finally figured it out this past Sunday, it's leaving the GC off the beginning of the cache ID. When I put it there and saved the file it worked exactly how it's supposed to. Anyone else having this issue?

 

This is probably happening because you are using GSAK to load your files and you are stripping off the GC when you export to your Colorado. If you use the default GSAK export settings, or better yet, the very cool GSAK export macro you can avoid this issue.

 

And lastly, although this one hasn't happened in a while (maybe since 2.7?)...I'm pretty sure it would happen when I was switching profiles between automotive and recreational (Pretty much the only 2 I ever use) that the Co. would CONSTANTLY switch it's self from Track Up to North Up.

 

Sounds like in recreational mode you switched the track setting to track up? Have you checked in _both_ profiles that the track mode is set to Track Up?

 

GO$Rs

[+g-o-cashers]

More testing with 2.8:

 

Accuracy was very good again over the test course this morning. PDOP was high, I only had visibility to 6 satellites in the clear and 4-6 under cover. Normally this is when I would see the drift on the Colorado but this morning it did very well. It is still a bit early to break out the champagne but at least things are heading in the right direction.

 

Here are the plots from yesterday and today. Yellow is the reference track at about 20' wide with the blue Colorado track underneath.

 

10/15: http://garmincolorado.wikispaces.com/file/...l/081015_CO.png

10/16: http://garmincolorado.wikispaces.com/file/...l/081016_CO.png

 

WAAS still behaves strangely. Most of the time (~75%) I WAAS to 51 and have WAAS within 30 seconds to 2 minutes. The rest of time I get 33 and WAAS takes a very long time, sometimes I lock to 33 after 4-5 minutes other times 33 fails and the unit moves on to another satellite until it finds something -- this process is very slow sometimes taking 10-20 minutes to lock with a reasonably clear view of the sky. If I toggle WAAS while the unit is going through this hunt sequence it will usually pick up 51 and lock within 60 seconds. What I don't understand is why my unit doesn't always start with 51 which is normally the best option in my area.

 

No problems with GPS elevation that I saw the first night.

 

GO$Rs

[+Red90]

I know it is really a different topic and you probably don't want to confuse things, but could you take the Oregon with you as well. It would be nice to get some real data to see if it is the same, better or worse than the Colorado with respect to reception in poor conditions.

[+Red90]

I'm hoping they release a standalone version of this firmware soon, since I have no desire to install Web Updater.

 

Garmin has not been releasing these as standalone downloads for awhile.

[+g-o-cashers]

I know it is really a different topic and you probably don't want to confuse things, but could you take the Oregon with you as well. It would be nice to get some real data to see if it is the same, better or worse than the Colorado with respect to reception in poor conditions.

 

I have a a lot of comparison data between the CO and OR on the 2.6 GPS firmware. Pretty scary for the CO but probably not of much value if 2.8 fixes the location errors. I'll add the OR to the mix in a couple of days but my sense is that the CO will be somewhat better that the OR.

 

My basic observation on the Oregon is that its position always seems to be delayed. There always seems to be lag on turns, while the 60csx and the CO make nice quick clean turns when you change direction, the OR lags behind and tends to "cut" corners. On straight runs the OR places you behind your actual location unless you stop and let it settle.

 

I think if you walked up to a given point and let all three units settle for 5 minutes they would all give about the same reading. I'm more interested in track accuracy under dense cover, especially while moving at walking/biking speeds, this seems to be a much more difficult test for the units than letting them sit in an open field trying to measure accuracy to a well known location.

 

GO$Rs

[+Crid]

I'm hoping they release a standalone version of this firmware soon, since I have no desire to install Web Updater.

 

Garmin has not been releasing these as standalone downloads for awhile.

 

Sorry to disagree, but I installed 2.51 beta, 2.60 and 2.70 all from standalone downloads.

[+Red90]

Sorry to disagree, but I installed 2.51 beta, 2.60 and 2.70 all from standalone downloads.

 

I'm talking about GPS Chipset firmware. Unit formware has been issued as standalone, but GPS Chipset firmware has not.

[+Crid]

I'm hoping they release a standalone version of this firmware soon, since I have no desire to install Web Updater.

Why??

 

Because I was under the mistaken belief that it was an app that sat in the background regularly "phoning home" to see if there were new updates. Having looked into Web Updater further, I now realise I was wrong.

 

Sorry to disagree, but I installed 2.51 beta, 2.60 and 2.70 all from standalone downloads.

 

I'm talking about GPS Chipset firmware. Unit formware has been issued as standalone, but GPS Chipset firmware has not.

 

My apologies. I misunderstood.

 

I've now upgraded to 2.80. With the nights drawing in I'm going to get less chance to do any decent testing after work, but there's still the weekends.

[+Red90]

I'm more interested in track accuracy under dense cover, especially while moving at walking/biking speeds, this seems to be a much more difficult test for the units than letting them sit in an open field trying to measure accuracy to a well known location.

 

GO$Rs

 

I agree. Track comparisons walking or running in heavy cover are the comparisons that make sense both for hiking and geocaching use.

 

Maybe a topic for a different thread. If you have your 60csx still, maybe do all three if you think it can be done without each unit affecting the others. Actual posted tracklogs would be handy as well.

[+g-o-cashers]

I agree. Track comparisons walking or running in heavy cover are the comparisons that make sense both for hiking and geocaching use.

 

Maybe a topic for a different thread. If you have your 60csx still, maybe do all three if you think it can be done without each unit affecting the others. Actual posted tracklogs would be handy as well.

 

I do still have the 60csx -- walking the same track with all three is a little cumbersome, not to mention my neighbors probably think I've lost it.

 

Any idea how close you can hold these units without having an impact on each other? I've heard people claim this but I've never been able to find any hard data on it.

 

GO$Rs

[+julianh]

I do still have the 60csx -- walking the same track with all three is a little cumbersome, not to mention my neighbors probably think I've lost it.

 

Any idea how close you can hold these units without having an impact on each other? I've heard people claim this but I've never been able to find any hard data on it.

 

GO$Rs

In all honesty - why not just put them all in an external pocket of your backpack?

 

Okay, okay, I KNOW that for best results, you are supposed to hold them in a particular orientation (vertical for units with helix antenna, horizontal face-up for units with patch antenna, etc), and with a clear sky view, etc, etc, etc, and for a truly scientific test, you should set them up on a rig which will give all units their optimal respective sky view, and so on.

 

But my point is - these are supposed to be high-sensitivity consumer units (not "scientific instruments"), capable of holding a lock under "challenging" real-world conditions. The "drift" problem that some models have exhibited is abosulety inexcusable in a personal navigation device, if it can be seen under even "moderately" sub-optimal conditions, with the unit being held in a reasonable orientation, as far as I am concerned. To be even reasonably reliable for personal navigation when hiking, there is just no way it should be giving an error of 50 metres or more under such conditions (unless you are REALLY deep in a canyon, or under tropical rain-forest canopy, or similar).

 

For what it's worth, my Summit HC has NEVER exhibited the "drift" problem, and I DO use it under tropical rain-forest canopy. The EPE which I get never blows out to unreasonable values. (The worst I see is deep in the "urban canyons", where my sky view is minimal, and there will be lots of multi-path errors. However, under even these conditions, the short-term position error is understandable, and more importantly, the unit does not "drift", and will self-correct as soon as I move back into a location with "reasonable" sky view.)

 

I have just upgraded to Software / Firmware 2.80 / 2.80, and it is still rock solid. Just this morning as a test I put it in my backpack, and put the backpack in the boot of my car for the drive in to work - 7.5 km through suburban streets. (Metal boot lid, back seats up, 2 passengers in the back seat for some of the trip, no sky-view other than what can leak in through the back seats). This is a pretty savage test of GPSr sensitivity. The only reason I bothered at all is because I know from prior experience that my GPSr is capable of giving good track-logs under such conditions.

 

Comparing today's track log with previous trips made with the unit mounted more sensibly on the dash, there is not one track point which is out by more than 10 metres in plan poistion, and elevation is good to 5 metres- indeed, almost the whole track-log is aligned with my previous tracks to within 5 metres - and that is pretty good, since it is a 4-lane road, so I could easily have been in a different lane on some of the previous trips. There is also not one pair of points separated by an implausible distance with an implausible time difference (implying an absurd "jump" speed).

 

That is, these high-sensitivity receivers CAN maintain good position locks under even extremely bad reception conditions. If they can't give a good track-log under "reasonable" reception conditions which might reflect how people might actually use them in the real world (e.g. carried in a shirt pocket, or the front pocket or shoulder strap pocket of a backpack), then they are fundamentally faulty.

 

On my criteria (which I think are not an unreasonable expectation nowadays, given the current state-of-the-art in consumer GPSrs), the Colorado and HCx models which exhibit "drift" are faulty and fundamentally "not fit for purpose". Thankfully, my Summit HC has never exhibited this fault, under any combination of software / firmware. (Which is odd, because all available information suggests the Summit HC has the same hardware as the Vista HCx).

 

Hopefully, the 2.80 firmware update will resolve issues for unfortunate Colorado and HCx users as well!

 

Good luck!

[+Red90]

Any idea how close you can hold these units without having an impact on each other? I've heard people claim this but I've never been able to find any hard data on it.

 

GO$Rs

 

Really, I have no idea. The same as you, mostly internet conjecture on the subject. Maybe you can bring a friend on the walk?

[+SimbaJamey]

I just installed the 2.8 update and the unit seems to do things (menu pages, map draws)

 

One new problem I've been having for a month or so is that my field-notes will no longer upload, the GC page kept telling me 0 records found. I finally figured it out this past Sunday, it's leaving the GC off the beginning of the cache ID. When I put it there and saved the file it worked exactly how it's supposed to. Anyone else having this issue?

 

This is probably happening because you are using GSAK to load your files and you are stripping off the GC when you export to your Colorado. If you use the default GSAK export settings, or better yet, the very cool GSAK export macro you can avoid this issue.

Thanks!

I figured it was something like that.

 

And lastly, although this one hasn't happened in a while (maybe since 2.7?)...I'm pretty sure it would happen when I was switching profiles between automotive and recreational (Pretty much the only 2 I ever use) that the Co. would CONSTANTLY switch it's self from Track Up to North Up.

 

Sounds like in recreational mode you switched the track setting to track up? Have you checked in _both_ profiles that the track mode is set to Track Up?

 

GO$Rs

 

The Automotive profile is set to automotive mode.

The recreational is set to Track Up.

But after switching profiles (and IIRC sometimes just randomly) it would switch on it's own to North Up on the recreational profile.

And it happened a lot...at least a dozen times.

Edited October 17, 2008 by SimbaJamey

[MtnHermit]

Any idea how close you can hold these units without having an impact on each other? I've heard people claim this but I've never been able to find any hard data on it.

Why would it matter? GPS receivers, are just that, radio receivers . . . passive devices. Their CPU's might radiate some EMI, but given their low power, not much.

 

Clearly a case where "One test is worth, One-thousand expert opinions."

 

Do one of your test tracks with all three rubber banded together, compare the tracks to previous single unit tracks, then you and we will all know. Besides, all that walking is good for your heart.

[+Red90]

Why would it matter? GPS receivers, are just that, radio receivers . . . passive devices. Their CPU's might radiate some EMI, but given their low power, not much.

 

People that have done testing have seen an affect on performance when units are close together. No idea why or if it happens with these units, but that is what others have found, so it is important to note when testing in case it changes the results.

[MtnHermit]

Why would it matter? GPS receivers, are just that, radio receivers . . . passive devices. Their CPU's might radiate some EMI, but given their low power, not much.

People that have done testing have seen an affect on performance when units are close together. No idea why or if it happens with these units, but that is what others have found, so it is important to note when testing in case it changes the results.

Based on your reply, you fall into the Expert Opinion Class.

[SiliconFiend]

Any idea how close you can hold these units without having an impact on each other? I've heard people claim this but I've never been able to find any hard data on it.

Why would it matter? GPS receivers, are just that, radio receivers . . . passive devices. Their CPU's might radiate some EMI, but given their low power, not much.

 

Clearly a case where "One test is worth, One-thousand expert opinions."

 

Do one of your test tracks with all three rubber banded together, compare the tracks to previous single unit tracks, then you and we will all know. Besides, all that walking is good for your heart.

Every radio receiver is also a tiny transmitter because the device has to generate a frequency that matches the carrier frequency it's trying to receive. That generated signal can leak out the antenna. That's the reason that airlines ask you to turn off even AM/FM radios in flight (to prevent any possible detrimental interference with the avionics). So, it's entirely conceivable that several devices tuning into the same frequency could interact with each other. Count me as another "expert opinion" I guess.

[MtnHermit]

Every radio receiver is also a tiny transmitter because the device has to generate a frequency that matches the carrier frequency it's trying to receive. That generated signal can leak out the antenna. That's the reason that airlines ask you to turn off even AM/FM radios in flight (to prevent any possible detrimental interference with the avionics). So, it's entirely conceivable that several devices tuning into the same frequency could interact with each other. Count me as another "expert opinion" I guess.

I was unaware of that. Learn something new every day.

 

However, I believe a field test is still valid. I'd do the test myself but I have none of the three units in question. But I will try the test with my Nuvi and eTrex on my next outing.

 

Thanks

[+g-o-cashers]

I've (inadvertanlty) done field tests with the three units held very close, sometimes in the same hand. I have no idea I've this had any affect, I can say that I've run tests like this and both units, held in the same hand, performed as well as they did in a standalone test. That would tell me that it might not happen all the time or maybe certain units are less apt to cause or be sensitive to the problem.

 

The inherent problem with this test vs. the test I do today is that you have to assume that in a standalone environment the receiver works fine and that the only thing that might introduce a problem is the fact that the units are held too close. In the environment where I do my tests I have lots of things that might cause problems (i.e. GPS software/hardware problems, foliage, the way I hold the GPS, etc) so eliminating this as a variable made sense because most people don't use multiple GPSs at the same time anyway. A test to measure these effects would be designed differently.

 

GO$Rs