oxothuk

I'm wondering if the problem folks are discussing here is the same one I encountered last weekend. I took a short hike on a route that I follow regularly, and at one point my position (which had been following the road on my map perfectly) suddenly shifted about a hundred yards east. This shift persisted while I walked another 45 minutes, and then corrected itself just as suddenly as it started. All of this was in an area with wide-open views, and WAAS on. I am also on 2.60/2.60

Like others have said already, the "inaccuracy" in Google Earth comes from misalignment of the satellite photos. They have to line up a photo which has some perspective distortion against a map of the earth, which also is not flat. I suspect (don't know) that they may fix the image on known landmarks when possible. Quite often if you turn the display of roads on and off you can see that the roads don't line up exactly with the visible image of those same roads in the satellite photo. It's usually pretty close, but not exact.

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.

1) There is no option on the Vista HCx that will give you a continuous real-time display of GPS altitude. 2) You can see an instantaneous display of GPS altitude with a menu option from the Satellite page. 3) You can record your tracks with GPS elevation rather than barometric elevation by making the following changes to the altimeter setup: Auto-Calibration - OFF Barometer Mode - Fixed Elevation

I also noticed that TOPO 2008 roads were a couple hundred meters off in my neighborhood. I could easily believe the error was due to a mismatch between NAD27 and NAD83 at some point in the process. But as others have noted, only some of the road locations are in error. The main roads outside my subdivision are spot-on, for instance.

Count me as one of your fans. While the TOPO 2008 coverage of Colorado isn't too bad (50 foot contours rather than the 130 foot contours found in other states), I find that your 40 foot contours are a lot smoother. The downside is that the extra detail taxes the processor on my VistaHCx a bit more, but that price is worth it IMHO. Plus, your map actually has the streets in my neighborhood positioned correctly (Topo 2008 has them shifted several hundred yards. Looking forward to the update.

Not to be argumentative, but a 37,000 foot crusing altitude (typical of most commercial flights I've been on lately) is at the top of the troposphere at US latitudes, with 75% of the air mass below. The troposphere only goes up to 65,000 feet in the tropics. According to Wikipedia at least - > http://en.wikipedia.org/wiki/Troposphere

If you are talking about the Mapquest TV display on Frontier - not much in the way of detail, and you have no ability to zoom in, although they do alternate among three different zoom levels (with commercials in between) . Also, they use a "plane" image for the map pointer which is so large that it's hard to tell where your current location actually is within 50 miles. Not complaing though - Frontier does rock. I've used my VistaHcx on a few flights and had slightly better luck on the south side of the plane. I can't see much use for WAAS though - not only are the atmospheric corrections irrelevant when 90% of the atmosphere is underneath you, but how much accuracy do you need in a position that's changing 900 km per hour?

I used my Vista HCx on commercial flights a few times, until the novelty wore off. Reception inside the airplane is fair to good, but sometimes I get dropouts. As others mentioned, you can get GPS (rather than barometric) elevations in the track log if you turn off auto-calibration and set the mode to "fixed elevation". There isn't any way to see a continuous readout of GPS elevation, but you can check it instantaneously from the Satellites page.

That, and I also saw the problem when snowshoeing.

AIUI, GPS elevation is very accurate over the long run (assuming the geoid model is correct in your neighborhood) but has a lot of random error variation from minute to minute. Barometric elevation, on the other hand, has relatively little random error variation from minute to minute but degrades over a span of hours as the weather changes. For that reason, combining a barometric sensor with automatic calibration based on GPS elevation should give the best of both worlds. The barometer smooths out the random errors, and the GPS auto-calibration corrects for barometric drift.

Thanks. I had read most of those threads already, but was hoping I had missed something. I also have a question about the MapSource options for Categories and for Display. Am I right that these options only have meaning inside MapSource itself? And it seems that they are lost when a waypoint is transferred to the GPSr and later retrieved. The Display option in particular is one I would like to use on the GPSr (ie, SymbolOnly for some waypoints). Is there another way to accomplish that?

I've been trying to figure out how waypoint symbols work on my VistaHCx, but a lot of it is still a mystery to me. It seems like MapSource has a lot more icons defined than my VistaHCx does. If I create a new waypoint and assign to some icon that the Vista doesn't have (such as the Ghost Town), then that waypoint is displayed on the Vista with just the standard blue flag. And it's clear that my original symbol assignment has been lost, since that waypoint shows up with the blue flag in MapSource if I retrieve it from the Vista. 1) Is there a list somewhere of all the waypoint symbols the Vista can display? I don't see such a list anywhere in the manual. 2) Is there a way to restrict the pulldowns in MapSource so that only the Vista's symbols will be available? 3) Is there a crossreference with the names that appear in a GPX file?

I just got Topo 2008 for my Vista HCx, and the first thing I noticed was that it shows the street I live on several blocks away from my actual location. The overall pattern of roads in my subdivision appears on Topo 2008 to be shifted a couple hundred meters north of their actual location. It seems like they applied a conversion from NAD27 to WGS84 on source data that was already WGS84; or something like that. FWIW, once I leave my subdivision, then my tracks on the main roads follow the mapped roads as expected. Now I understand that all maps have some errors and street navigation is a secondary feature in Topo 2008. But I'm just wondering: (a) how common are errors like this in Topo 2008 (i.e., what fraction of streets can I expect to be mislocated)? ( is there any mechanism for reporting such errors so that they get fixed in future versions?

Probably just means they want to offer the same unit for sale in Quebec, without having to keep separate stock.

You might look into getting a card like this to add a serial port for your new computer. http://www.newegg.com/Product/Product.aspx...N82E16815166003

Cables can be found on Amazon or e-bay for about $10. Just factor that into the price if the unit you are looking at doesn't come with a cable.

I don't think these two "Vistas" - Garmin Vista HCx and Microsoft Windows Vista - have anything in common. When you say the eTrex Legend doesn't work with your Vista computer, what exactly is it that doesn't work? MapSource? USB drivers? Something else? There are lots of threads here about the Vista HCx. I have one and love it - great sensitivity, nice readable display, and a compact form factor. But none of that has anything to do with the PC hookup, where the only real variable is whether you use a serial or USB connection.

I think the problem is that the licensing makes it too "limited" to be thought of as "ownership" at all, in the common sense meaning of the word.The steep pricing for these maps also makes buyers feel entitled to more ownership than the license terms are written to allow. And of course it's inconsistent with the way licensing works for most other software or games, which isn't tightly bound to a specific device. Finally, the whole scheme of "unlock codes" and "mother, may I" is overly intrusive and frankly offensive to me as a customer. I'm not well enough organized to keep track of all these little codes, and I don't like companies that take advantage of that. I wouldn't buy a toaster that had a key to keep track of - would you?

Right, but that only gives an instantaneous reading. There isn't any option of show "GPS Elevation" as a continuous readout on any of the other pages.

Well, I knew the cabin was pressurized. I was curious if one could find the "pressure altitude" using the GPSr's barometer, as I saw a post that said you could. Most cabins are pressurized to an effective altitude of 8,000 ft MSL, so I was curious if something like the 60 CSx could display both the "pressure altitude" and the actual altitude as calculated by the satellites. Just something to wow your seatmate with on a long flight... & yeah, i'd kick myself if I forgot it, too! But I'll bet that beauty would be tied to me six ways from Sunday! Gravity can be quite unforgiving... Later, Tom With the 60csx you can get a continuous readout of the barometric elevation. I haven't tried it on an airplane, but I expect it would just show 8000 feet plus or minus variations in the cabin pressure. You can get an instantaneous reading of the GPS elevation (from the satellite page), but not a continuous readout. Other models without a barometric sensor WILL give you a continuous readout of GPS elevation, since that's all they have. I've done that with an old yellow eTrex; it's cool to see it show 12 KM elevation and 900 km/sec speed. Oops, I meant 900 km/hour. 900 km/sec would be the express flight to Mars.

Well, I knew the cabin was pressurized. I was curious if one could find the "pressure altitude" using the GPSr's barometer, as I saw a post that said you could. Most cabins are pressurized to an effective altitude of 8,000 ft MSL, so I was curious if something like the 60 CSx could display both the "pressure altitude" and the actual altitude as calculated by the satellites. Just something to wow your seatmate with on a long flight... & yeah, i'd kick myself if I forgot it, too! But I'll bet that beauty would be tied to me six ways from Sunday! Gravity can be quite unforgiving... Later, Tom With the 60csx you can get a continuous readout of the barometric elevation. I haven't tried it on an airplane, but I expect it would just show 8000 feet plus or minus variations in the cabin pressure. You can get an instantaneous reading of the GPS elevation (from the satellite page), but not a continuous readout. Other models without a barometric sensor WILL give you a continuous readout of GPS elevation, since that's all they have. I've done that with an old yellow eTrex; it's cool to see it show 12 KM elevation and 900 km/sec speed.

After using my Vista HCx for less than a week, the barometric sensor suddenly stopped working. Symptom was that the elevation display showed 20000 meters and the ambient pressure display showed 0.00 millibars. Visual inspection of the porthole showed no obstructions (nor did I suspect any). I tried several things to see if they might fix the problem - change batteries, re-install firmware, hard reset (rocker-page-power) - without any improvement. Fortunately I was able to exchange the unit for another one at my local REI, without any hassles. But I'm just wondering how reliable these sensors are. Since the Vista doesn't have an option to display GPS elevation instead of barometric elevation, the unit is pretty worthless if that sensor breaks.

I picked one up at my local REI on Saturday and have been pretty pleased so far. I was worried about the odometer bug, so after updating the firmware to v2.40 I took a short stroll around the neighborhood yesterday carrying the Vista along with my old yelow etrex. I'm happy to say that both units showed 2.01 km as the distance traveled, and when I uploaded the tracks I got 2.0 km as the distance. The track on the Vista looked a lot smoother, though, and closer to the way the circuit I took appears on a street map; and no, I don't have any street map software, so it was not rubber-banding the track. Close enough. I'll have to check again on my next hike in the mountains, where I'm usually walking a bit slower.

The built in basemaps don't have very much detail - they'll just give you a taste of how the mapping features work. If you really want to use the mapping features, you'll eventually need to get one of the map products. In the meantime the unit will work just fine with the basemaps - it will be like having basic Etrex, only with a nicer screen plus a compass and altimeter.