GPS Information.net Forum >

I recently purchased a GPSMAP60CSx receiver, and initially was very much enthralled with the apparent higher sensitivity. It was in fact quite impressive. But as I worked with the unit some very disturbing events occurred.

I found that my unit displayed a significant propensity to "goofy navigation" even when out in the clear. Over a period of just two weeks I experienced several episodes in which the reported position would start drifting off true by amounts of several hundred feet. Things would deteriorate to the point where the track log would show movements totally unrelated to my actual movements, and even do strange things like showing the track arrow moving sideways, etc. Most of these episodes were observed while walking out in the clear, with the unit indicating strong reception of numerous satellites.

My sanity check has been to do a bunch of walking around with my old trusty GPS V, and so far have seen no corresponding effects. So I remain convinced that the '60CSX was having special problems.

I realized very early on that the more sensitive receiver (I prefer the term "weak signal-tolerant") would expose the user to larger than accustomed errors in conditions of weak or otherwise impaired signals, due to poorer S/N and/or multipath. And my thinking was that the newer receivers could still be of considerable benefit under forest canopy where signals are weak but not necessarily afflicted with much multipath, since the poorer S/N should be at least partially offset by the continuing availability of more "locked-on" satellites to use in the solution. I had no expectations of the newer receiver helping much in "urban canyon" situations where reflected path signals are likely to dominate the error picture.

But it was a real shocker to experience problems in good signal conditions, and I am casting about for an explanation. Is it possible that the newer receivers are tracking weak reflected signals that older receivers could not track, and are incorporating these reflected signals into the solution with significant weight?

After fooling around with the '60CSx for about 2 1/2 weeks I made the heartbreaking decision to return the unit to the seller for a refund before time ran out. I had tried to get some information about the problem from Garmin, but the only response I received was a very terse suggestion that I update the firmware. I did not do so because the release notes made no mention of addressing the problem, and because of the risks in the event something went wrong with the download.

Has any other reader experienced this problem with one of the new breed of receivers? Is there anyone who really knows GPS technology who can comment on my observations and (hopefully) give me some justifiable optimism that this kind of problem can and will be corrected? It really was a painful decision to turn my unit back in- it was a shattered dream.

Thanks.

I have had a MAP76CSx for about a month now. I have used it both hiking in the mountains under tree cover and out in the open desert driving in my car. I have not experienced any location drift and the unit has remained very accurate in every condition I have used it. I much prefer the new receiver to the older less sesitive units. My last one was the Garmin Map76S. My guess is you may have had adefective unit.

Apart from its unwillingness to recognize WAAS, I have not had any problems with my GPSMap60CSx, despite heavy use since I got it 2 months ago. I am using software version 2.62 beta.

Sounds like you got a lemon. Bitch mightily to Garmin -- that might help us all in the long run!

Cam

Hello gps_lover!

I think your gps worked just fine, let me explained what i think happened.
Garmin maps (mapsource) have alot of dirt roads that are not placed precisely where they actually are...they are off even by hundreds of feet.
Now! your GPSMAP60CSx receiver is also a car navigator and it has a fonction called (Lock on Road) which will force the receiver to track on
to the dirt road (Garmin's dirt road) which is not placed where you actually
are(the real dirt road) So the receiver is stuck trying to trace a track between
two places and voila! we have goofy navigation!

So here's what you could about it. Go on the menu page, select SETUP,
Then select the MAP page. Now on this page you will see the (Lock on Road) fonction. select OFF !

You are now ready to hike offroad without being bothered by the goofy navigation part.[img][img]http://img165.imageshack.us/img165/1415/gpslover7dd.png[/img][/img]

By the way! Don't forget to put the Lock on road ON again when you use your receiver as a car navigator.

Actually, I leave it off all the time now and its worked great. I assume because the accuracy is so excellent.

I don't think the "lock on road" theory acounts for my problem, and
here's why:

For at least one severe episode of my "goofy navigation" I definitely
had "lock on road" turned OFF. One other severe episode (the first that
I noted) occured before I had installed any map data. Although I'm
not absolutely certain of this, I rather doubt that road lock would be
operating in the absence of any street-level map data being loaded.

One other suggestion was made that I simply could have had my hands
on a defective unit. But I'm having trouble understanding how a unit that
works at all could be acting this much differently. Except for the
RF/analog front end, all is done digitally. The front end must have been
OK, otherwise the unit could not have been working at all. And, as we
all know, digital stuff always works the same. Or, am I missing
something here?

Thanks.

Hello again gps_lover!

Well, your right about the unloaded maps in the receiver. the lock on road fonction would have no affect whatsoever if there are no maps loaded in the receiver, unless you were walking next to a highway included in garmins
basemap. which in unlikely.

Was your gps on energy saver mode ? On energy saver mode your gps doesn't track continually. But i doubt it would have large impact.

Hello again-

One other thing: of the two most severe episodes of goofy navigation I experienced, one was with WAAS ON, the other was with WAAS OFF. I had turned off WAAS to deal with the "failure to permanently re-acquire sats following coming out of a tunnel" problem, and doing so did indeed solve that problem.

Also, in all cases of the goofy navigation I observed, I was some distance away from any major roads- probably in excess of 1/2 mile.

Incidentally, I agree with the opinion that others have expressed, that WAAS is of little or no real benefit when one is driving around on the surface. Here in Oregon both sats 35 & 47 were very low on the horizon, although with the move in progress #35 has had much better availability lately. I had been trying WAAS mostly out of curiosity.

Thanks for all the suggestions, and please keep them coming. I'd really like to find out what was going on and find a fix. Except for this business I was really in love with that receiver.

I live in Quebec city in the province of Quebec, Canada, and Wass hasn't been working here for a while and will come back only in the fall. The Wass satellites are being moved to a new location so that everyone in north america (including eskimos) will be able to use Wass. So far i haven't seen
anyone experiencing goofy navagation because of Wass not working except
those leaving a bar in the middle of the night.

I dont know if this is the same thing but I am having a similar problem where the map starts to turn while walking but if I switch the electronic compass off all is well. Hope this helps.