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AlunS

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Everything posted by AlunS

  1. IIRC you gain a bit more as the number of track points is reduced also (a typical 2000 point log is reduced to about 500 points in my experience). It all rather depends on how long you're out in the wilds, and not able to transfer the track logs, and how many track points you're generating (which in turn depends on your track log settings). The Vista HCx only has space for 10,000 track points (if you only use the active log, that is), and after that if you don't have any means of transferring them you're screwed. It'd be a shame to lose important information for the sake of, say, $15 for a 2GB memory card or even less for a smaller capacity card. On the other hand, if you want to save a few dollars, and you're only out for a limited period, you can just make sure you don't run over the 10,000 limit (and make sure you don't delete the active track log if you do a reset from the odometer page!!) and split the track log up afterwards. You can do this in Mapsource, or a host of other programs. I just like the extra security of knowing that in addition to the active log I always have a record of every move I make on my memory card as well. I guess everybody has their own way of doing things.
  2. So the .gpx-stored tracks on the card contains the timestamps? Neat. I've never looked at them. Yep, everything ... latitude, longitude, elevation and timestamp. The memory card is the reason I bought it over any of the other models without it, so that I could forget about saving tracks to external devices when on multi-day trips, or losing valuable data.
  3. Unfortunately no. When you save a track it strips lots of information from the track log including time stamps. However , all is not lost. Get yourself a microSD card for your Vista HCx and set it up so that it continuously records track logs in GPX format to the card (Track Log -> Setup -> Data Card Setup and tick "Log Track To Data Card"). This will create a track log for every day with the name YYYYMMDD.gpx on the data card. You can then connect your Vista HCx, put it into Mass Storage Mode (Setup -> Interface -> USB Mass Storage) and simply open the appropriate files in Mapsource. You may find multiple tracks within that one file, if you've enabled/ disabled track logging or switched the unit off and on again.
  4. Just Google "3 km/h in mph" and it'll tell you that it's 1.86411358 mph But if you've got your GPS set to imperial units, it'll give you mph as an option. You can enter whatever figure you want for this using the "keypad" that pops up, but the other option ("for more than") only allows a discrete number of choices from a drop down menu.
  5. There are settings on the Vista HCx (and other units that have an electronic compass) that determine when the compass kicks in. At all other times the "compass" page actually uses the current direction as determined by subsequent position fixes instead and the compass itself isn't used. Go to Settings > Heading and look at the values for "Switch to compass heading when below" (enter a speed here below which the compass is used) and "for more than" that tells you how long you have to be travelling below that speed for it to take over. I have mine set to 3 km/h and 15 seconds, but I seem to remember the default value is much higher, which may mean that the compass is never used under normal walking conditions.
  6. Awfully sorry, I was only trying to be helpful. I wasn't "testing for the bug" just going for a walk as I do every weekend
  7. Went out yesterday with my Vista HCx (2.50/2.60). The odometer read 21.3km and the total according to the track log was 20.45, which is about the order of magnitude of difference I always saw on my old Venture. I have no idea why there was a difference at all with my old GPS, but at least it's around the same level of difference, and not the crazy differences that were reported with the older revisions. How speed did you average? Anyone that keeps up a steady pace over 2 mph won't see the issue. It's when you are going through slow or steep terrain where the problem would occur. Overall Avge was 3.7km/h including two breaks, and moving average was about 4.7km/h IIRC. Sorry I don't 'do' miles
  8. Went out yesterday with my Vista HCx (2.50/2.60). The odometer read 21.3km and the total according to the track log was 20.45, which is about the order of magnitude of difference I always saw on my old Venture. I have no idea why there was a difference at all with my old GPS, but at least it's around the same level of difference, and not the crazy differences that were reported with the older revisions.
  9. I updated my above post with some more data. unfortunately it only serves to confuse the matter, I'm afraid! I've looked at the document defining the Garmin PVT protocol on their website, and apparently the altitude information is transferred in metres as a 32-bit floating point number during track download, so no real excuses there. I can't explain why they would save the internal GPX track to 3 decimal points and then transfer the track log as a floating point number and then truncate / round it to 0.5 metres .... strange. Also, if I use OziExplorer or GPS Utility to record my current position in real time, rather than downloading a track log it seems to have a much finer granularity (both programs only display to one decimal place, but there are points with, say, only 0.1m difference in altitude, so the 0.5m granularity definitely isn't there). My head hurts!
  10. Interesting ... I've got over 5 years worth of track logs from my old Venture in OziExplorer format which records altitude in feet (only to one decimal place though), and what you're describing does indeed seem to be apparent. You can see it most clearly on sections of the track that are largely flat(ish). I've only used my Vista HCx twice so far, and on reasonably hilly terrain, so maybe the effect isn't obvious in those logs, so i may have to eat my words when I said it wasn't apparent on this unit I'll try that test you suggested. EDIT: Indeed I set it outside on a table for a while and then lifted it above my head and put it on the floor for a bit and the only altitudes measured in the log (as imported into OziExplorer) were 54.9, 55.4 and 56.4 metres which would tend to indicate a 0.5m granularity. It's not based around an integer value though, which is why it doesn't immediately spring out at you in a more chaotic 'normal' track log (I'd first looked for just either .0, or .5 after the decimal point). However, and this is odd, the GPX file saved to the memory card is showing very different values, with no altitude being the same over that period to within 3 decimal places. I wonder whether there's some limitation in the Garmin PVT protocol preventing more precision in the altitude being transferred over the USB or serial connection, somehow? Unfortunately I can't upload files here, and they're a bit too long to quote in their entirety, but here's a small 10 second section from each covering the same time period for comparison. In the Ozi file, the 4th item is the altitude, in feet for some weird reason, and in the GPX file it's in metres, but you get the drift ...
  11. What makes you think that? Certainly in the GPX tracklogs that the Vista HCx writes to the memory card, there's no indication of anything like that and I see altitudes (in metres) with significant digits down to 3 decimal places both there and in the track logs I download into OziExplorer. If what you say is true, I'd only see multiples of 0.5m (which is what I assume 1.572 feet is!)
  12. OK, so I went out hiking yesterday with my Vista HCx (at 2.50/2.60). Started at an altitude of 228m and climbed steadily to 555m. The total ascent at this stage showed as 131m!! At the end of the walk (altitude 208m) Total ascent showed as 376m and total descent as 409m. I put the track through an analysis program and it came back with 1192m ascent / 1212.7 descent which is way over the top I think, and probably caused by insufficient smoothing / filtering. The terrain was very uneven (covered with what are known in these parts as "peat hags", if you know what these are), but looking at the altitude profile and adding up the really significant height gains by hand, I'd say the truth was probably closer to 800m total ascent. There's clearly something wrong here, and I'm leaning towards the explanation given that it, as well as the Trip Odometer are somehow velocity driven rather than driven by changes in horizontal or vertical position, or maybe there's some kind of minimum speed filter in place as there possibly was in the case of the latest 2.60 GPS s/w update. In any case, for it's primary intended purpose, i.e. outdoor pursuits that normally imply slow speeds, it makes this display essentially totally worthless. Does anyone know if the older units with barometric altimeters, such as the Summit suffered from similar problems? @groth: Have you had any kind of reply yet from Garmin on this matter?
  13. Had this problem with mine today for the first time. It had been in in the house all day at 20C, and was in the car driving to the start of the walk for no more than 30 minutes. Outside temperature was about 3C. Switched it on and got the washed out screen, switched it off and back on again immediately and it was OK. My wife's venture HC which had been in exactly the same conditions was fine.
  14. Just to say that I've just gone through my home made contour maps with MapEdit and cgsMapper (which is a real PITA!) and converted them all to non-transparent and now the cross-hatching has disappeared. I've disabled the basemap which was next to useless anyway, and the error circle has gone down to the same order of magnitude I was used to on my old non-mapping etrex Venture! It still isn't the same diameter as the displayed EPE, but at least it's less of a distraction than it used to be.
  15. To disable the map, go to the map page, select menu>setup map, move the cursor over to information, press the menu button again and select either "show none" or "hide basemap". However, the "accuracy circle" still shows - about 20m radius when my GPS is showing an EPE of +/- 6m (30m at +/- 11m). It wouldn't surprise me if the "accuracy circle" is based on 95% probability, while the EPE is one-sigma, or some such thing. However, I can't yet find how to turn off the "accuracy circle' completely. You're a star! I hadn't thought to hit the menu button again once I'd selected the information tab. It is very briefly mentioned in the manual, now I read it more carefully, but it only says you can do it, no mention of what options are available, otherwise I might have twigged earlier. I'm normally quite good at discovering every single option in kit like this, so I'm a nit surprised I missed that one! My 'home made' contour maps I mentioned still display OK, although the whole map is covered with cross-hatching which is a little irritating though. EDIT: Apparently this is because the maps are defined as being transparent, and when there's no underlying basemap that's what it shows for some reason or another. There's a link on the page where these maps are stored that points to instructions for making them non-transparent, so it looks like I'm saved.
  16. That would be great, and a much better use of software resources than useless stuff like games I've seen references on the net that suggest that on units that support the disabling of the basemap the circle then reverts to representing the real EPE. I only bought the Vista HCx because of the high sensitivity receiver, and the fact that I can set it up so that it automatically records track logs to the memory card. The limited mapping that is available is of no use to me really, and if I could have got a non-mapping unit with those features, I would have done. Now what i'd really be interested in would be something that I could upload my own scanned in and calibrated raster maps to!
  17. Doesn't seem to make any difference on my Vista HCx .. the circle is still there.
  18. With my nuvi 760, if you fire up POI loader, when the screen appears with the "Find Device" button, the default I see is "GARMIN (E:\)". If I click on the little grey arrow button on the drop-down box though it lets me see other removable drives, including the one that represents the SD card on my nuvi, which is G: in my case.
  19. Replying to my own post here Anyway, after some extensive Googling, it would appear that on some Garmin GPS's (including the 60 series and the GPSmap 76 series) it's possible to completely disable the basemap which might be the answer to my problem. Does anyone have any idea if this is possible on the Vista HCx or it's siblings? Another option might be to edit the basemap somehow to fake a higher accuracy if I could get at it somehow.
  20. I use my GPS for hiking only, (I have a nuvi for the car) CityNavigator or MetroGuide wouldn't be an awful lot of use for that There are no topo maps available for Ireland , and in any case even if there were, if the quality was anything like what I've seen on the latest UK topo maps, I wouldn't bother. I do have some 'home made' contour maps that were created by the SMC (Scottish Mountaineering Council) based on processing of Shuttle SRTM data that covers the whole of the British Isles which are better than nothing. Anyway returning to the subject, I kind of understand the logic in what you said about the accuracy of the underlying map, but for the application I use it for, i.e. hiking, the only map elements that mean anything in that context are waypoints I've put in there myself. I personally couldn't care less what the positional accuracy of a road intersection 10km away is. I'd at least like the opportunity to turn this 'feature' off, and have the circle just represent the current EPE. As it is it's just an annoying distraction.
  21. My Vista HCx does the same. I see loads of track points in the log with the same position as when you switched to "Use with GPS Off" with only the elevation data changing and nothing else. Also the altimeter related fields in the Odometer page such as Total Ascent also continue to update (even if you've stopped track logging altogether in the Tracks screen).
  22. I've come across the same thing. On my old Venture you'd rarely even see the accuracy circle unless you were zoomed right in close, but on my new Vista HCx it's huge all the time. Even when I have a +/- 3m fix, it's still (comparing it with the scale on the bottom left hand corner) about 300m in diameter, i.e. about 10x what it should be. I asked the same question on Usenet and someone claimed that the size of the circle also reflected the accuracy of the underlying map (whatever that might mean) which in my case (since I'm in Ireland where there are effectively no maps available) is the basemap. Sounds like bullsh!t to me, TBH.
  23. Just run Webupdater .. it tells you the main s/w is up-to-date, but then offers to look for additional software or something like that. The new GPS s/w is offered in that screen.
  24. When I run Webupdater it says "GPS Chipset Type M2 (Region file)" and no Change History. Great description there Garmin It is version 2.60 though according to the Main Menu -> Setup -> Software version screem. I also updated my wife's Venture HC which uses the same chipset. It does however, "hang" in the Transferring Data screen on the GPS itself and doesn't automatically reboot like when you update the main software, and requires a power off/ power on cycle.
  25. I'll be interested to hear what you find. I just posted my results - same problem. My software: I'm a Mac user, so I use MacGPSPro to upload the track log. Then I have a homebrew Excel template that I use to calculate distance, time, speed, climb, etc. from the uploaded track log. - Ed Sorry, wasn't feeling too well at the weekend, so I didn't go out after all. Hopefully I'll be out next weekend. I've found some software for the PC that will analyze GPX track logs and spit out all kinds of useful info including total ascent. It's in German though, so maybe not for everybody
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