Hertzog

No, he mentioned that on his return trip the reported barometric pressure changed by 0.17 in Hg, but with autocal the 76 calculated barometric pressures to within 0.02 in of the reported values; without autocal the GPS would have assumed that the 0.17 in change was due to altitude changes, and the barometric pressures calculated by the 76 would have changed little if any. Oops, sorry julian, when I wrote this your more detailed response had not shown up on my computer; anyway, consider it a seconding of your response.

I've had a few headaches thinking about this as well. Here's my take: 1. The fixed/variable elevation setting doesn't affect the barometric elevation calculations at all; they go on independent of this setting. 2. The fixed/variable setting affects how the barometric pressure gets calculated from the ambient pressure and the barometric elevation. In the variable elevation setting it seems pretty evident that it is taking the ambient pressure and and changing it by the current barometric elevation reading, based on the standard pressure altitude curve (or maybe some digital approximation to it) to get the barometric pressure. However, in the fixed elevation mode it looks to me like it is reverting to the last manually calibrated elevation, or possibly the elevation you would have had at the time of the switch if you hadn't been in autocal; in any case, it doesn't look like it is using either the autocaled barometric elevation or the GPS elevation at the time of switch for it's barometric pressure calculations in the fixed elevation mode. OK, now MY head is spinning

In the fixed elevation mode the elevation data field will still display the barometric elevation, so you could manually record it during a test. As you say, not an "easy" way to do it. However, another approach you can use is to connect to nRoute during your tests. nRoute always logs the GPS elevation, so you can operate normally and end up with simultaneous track files of both elevations. Should work great at home or office; but not too good for field trials. (Sorry I haven't mentioned this before; I've been following your posts with interest, but been too preoccupied with other matters to really get in and digest them. These are the types of tests I've liked to do myself, but haven't done them with your rigor.)

That doesn't sound like normal operation; although they have possibly made some changes to the software algorithms, it should still work basically the same as the 60CS. I wonder if the vent hole for the altimeter has somehow gotten plugged up. As a sanity check look at the ambient pressure to see if it is consisent with being back at 700 feet, or if it is still reading 5600 feet pressures.

This is true for the 60CSx and 76CSx as well (the 60CS an 76CS and earlier models did consume a signifcant amount of power, but Garmin evidently redesigned the electronics starting with the CSx models).

FWIW, I did a little googling and came up with this link: http://www.gpspassion.com/forumsen/topic.asp?TOPIC_ID=101914 that describes the (probable) changes.

People are also saying that between the 60Cx and the Colorado, the Colorado is the best for geocaching, so if that's within your budget you ought to consider it (I'm a dedicated 60CSx fan myself, but if I were looking today I would be taking a hard look at the Colorado).

Typically, in Word I get something like this: ACTIVE LOG062429 -7.948 2007-02-17T14:24:29Z -8.170 2007-02-17T14:24:30Z -8.096 2007-02-17T14:24:31Z ACTIVE LOG063319 -8.804 2007-02-17T14:33:18Z Whereas in WordPad I get this with nice readable tabs, although they don't show up in this reply): <?xml version="1.0" encoding="UTF-8" standalone="no" ?> <gpx xmlns="http://www.topografix.com/GPX/1/1"'>http://www.topografix.com/GPX/1/1" creator="" version="1.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd"> <trk> <name>ACTIVE LOG062429</name> <trkseg> <trkpt lat="33.899141" lon="-118.360052"> <ele>-7.948</ele> <time>2007-02-17T14:24:29Z</time> </trkpt> Whenever I try to open with IE as twolpert suggests, it seems to want to default to MapSource; likewise, if I try to open with "XML Editor", which my systems thinks I have but I haven't been able to find. As you might have guessed, I probably have some very screwed up system settings somewhere, maybe in the Registry (I have some similar problems in other unrelated applications). Anyway, I'll just plug along with what gets the job done; thanks for the good thoughts.

As you noted, they're just text files. What error message have you received when trying to open them in Word? I often edit GPX, KML, and similar files in Word. Patty No error message, it just shows limited results in Word. I did a little investigating today, and it looks like you can't load an hml converter if you have Office 2003 Small Business Edition (which I have). Since I can pretty much do what I want in Word other than this with what I have, I'm not about to pay $$$ for this capability, so I'll just stick to what works for me (WordPad).

If you want to get a feel for how the file is organized, you can open it in a text editor. In my setup I get the best results with "WordPad" (I would prefer to use "Word", but haven't found an option to opening it properly there).

Likewise; I always pause a minute to let the 60CSx acquire. I don't think it's a problem unique to the 60/76 series; I first encountered it on my original B&W Vista years ago, when I was driving around town and wondering why it was having some much trouble aquiring!

I'm not that familiar with the Nuvi, but if you have a CD card in it the fall may have jarred it out of position. Try removing and reinserting it if you can.

Do the Colorados have a "Battery Save" mode? On other Garmins (e.g. the 60CSx) numbers like this almost always arise when people have put the unit in the battery save mode, not realizing that this significantly degrades the accuracy of the unit. I've downloaded and looked at the 400 manual, and don't see it mentioned in the setup, so they may have done away with it in the Colorados. In that case this may be some other issue.

One thing not mentioned here so far is that the micro-CD card mount is different in the two units. I have only used the 60CSx, so don't have direct knowledge of the 76CSx, but my impression is that on the 76CSx insertion and removal of the card is easier.

I don't have any answers, but thanks for the link; it looks like it might be interesting to explore. EDIT: I just downloaded it, and basically it gets installed in your adobe reader. Since I don't have any geo referenced pdf files, all the menu items were greyed out, but they look very useful if you download one of the GeoPDF files. Also, you get an informative email reply from TerraGo when you download it.

As StarBrand says, your numbers are not unusual, if not the best. I tend to get those kinds of numbers under good but not excellent conditions. Those situations were more common with my earlier B&W Vista and 60CS than with the newer more sensitive 60CSx. You should check to make sure you are not in the "Battery Save" mode, but your numbers would have been extremely good for the Battery Save mode, even with the best of conditions.

Google Earth opitons can be changed to display in any of the usual formats, and so can the HCx, so conversion is not a real problem. Actually, I've found that Google Earth and MapSource are now pretty "intelligent" about formats; if you type in a latitude or longitude in a format they are currently not set to, they will realize this (within reason) and do the conversion for you.

I would just use Google Earth; find the campground, mark it, read the latitude and enter it in the HCx.

It's 95%, according to Garmin documentation. But I cheated. I actually looked at the manual. Although as previously noted Garmin won't tell, I believe that their intent is for the EPE to be more like a 50% confidence number; the 95% in the manual is in regards to Garmin's stated accuracy specification. In my opinion (purely gut feel as I don't have any hard measurements to back it up - wish Garmin would make the EPE readily collectable data), the EPE is proabably better than a 50% number, maybe 60 or 70%; but I generally treat it as a 50% number to be conservative.

Unfortunately, we have about as much "hope" for this as CowboyPapa has for us to come around to his point of view I don't know why they won't add this, as you say "simple" feature; we've only been asking for it for the last 5 years or so, but in their infinite wisdom Garmin seems to be adament about saving us from ourselves. As to your question about viewing the GPS profile, I'm not sure how it would work on the Vista; on the 60CSx the elevation plot (over time) seems to be showing me the barometric elevation on the far right and in the digiital readout at the bottom, but the rest of the profile looks to be the GPS elevation. If I push the left button to pan the profile, then I get the GPS elevation in the digital readout. The most recent value at the right of the profile always remains the barometric reading. My earlier comment on using the Zoom features may have been a red herring.

You might want to look at the Mississippi Dept of Transportation website: http://www.gomdot.com/Home/Default.aspx They have a lot of map info in pdf format; don't how much use it will be to you for your effort, but good info to have for refererence.

That's a good point. This question comes up so frequently on the boards it's clear that a lot of people aren't aware of it. And no wonder, since Garmin doesn't see fit to even mention it in the manual! I thought they did, but can't find any mention of it now.

Accuracy numbers in this range are often an indication that you have the unit in battery save mode. It may not be your problem, but is something to check on.

For what it's worth, I just tried it and don't see any problems. I have 3.60/3.00 loaded, which I believe is the most recent software. I generally avoid the webupdater (for the 3.60 portion). Have you tried a master reset to see if that clears it up?

What does the real-time altimeter display show in this case? It still shows the barometric elevation (e.g., "cabin presure altitude)"). But the GPS elevation will be stored in the track file. If you fool around with "Zoom Ranges" and scrolling on the Altimeter page you may be able to get it to display the GPS elevation. I haven't actually done this on a pressurized aircraft. but it definitely changes the plotted elevation from the normally displayed calibrated barometric elevation to some other elevation.