No announcement yet.

GPS errors at start of runs. Can see it on the map.

  • Time
  • Show
Clear All
new posts

  • GPS errors at start of runs. Can see it on the map.

    Does the v2.2 revision fix anything for the problems at the start of runs. 1/2 of my maps have large spikes in the path data in the first 0.05-0.1 mile. Which also screws up the pace of the first mile. I never saw this with my 305.

    610 is still showing about 1% less distance than my 305 on courses that were consistently the same over 3 years.

    Look at the start of this run.

  • #2
    There are no changes in the 2.20 update that would address this issue. Do you generally start as soon running as your device has acquired a fix? The locating satellites indicator will clear when device is able to determine your location, but it can take a little bit longer to obtain a high level of accuracy. Some other forum users have suggested checking the GPS accuracy before starting, which can be found on the GPS status page in the menu, or can be configured as a data field. The GPS status page can also be viewed by pressing and holding for about 5 seconds on the locating satellites overlay.


    • #3
      Nope. I walk to the end of my driveway. Stop. Go to System > GPS > Satellites. I see the accuracy. On this mornings run it was as low as 10ft. Hovering between 10-13ft at the start of run. I wait until it is 15ft until I start. I take a step or two and then hit the start problem.

      I still have v2.10. It did not update automatically this morning. Do I need to do something for it to update to v2.2.

      Is this GPS chip in any other Garmin watches?


      • #4
        If you follow the link in the sticky post about the 2.20 update, you will find the update interface that will send the software update down to the ANT Agent to be uploaded to your device.

        The 610 uses the SiRFstarIV chip (as indicated on the SiRF logo found on the product box). This is the same chip that is used in the Forerunner 110 and 210.


        • #5
          I did my first run today, after picking up my FR610. I also noticed that for the 1st km, the GPS track was way off. I did wait until it had acquired a fix before setting off, but didn't check the accuracy. As I'm upgrading from a Nike+ SportWatch, which actually had no problem tracking me from the start on the exact same route, this is a bit disappointing (how I wish the 2min/km pace was true ;-). It also briefly activated auto pause in the first km, even though I had it set only to activate with zero movement, and I'm using the foot pod too, so that was also disappointing (even with an iffy GPS signal, shouldn't the fact that I'm running, and the foot pod is going, mean it shouldn't have auto-paused?)

          I'll check the GPS status accuracy the next time I run, to see what it says.


          • #6
            I got my 610 yesterday ant have not had time to run with it yet, but I walked with it on my lunch break and did 6 starts and stops.

            I found that the GPS accuracy is somehow affected by the pressing of the start button. A few seconds after pressing start the accuracy goes from 4m to over 50m in some cases, after that it goes down to 4m again.

            When uploading the tracks to sporttracks the GPS-points are all over the place in two of the starts and then settles down into a normal course. In the other 4 starts the GPS track is good from the start even though the accuracy was way off in those starts too.

            I uploaded my testwalks to garmin connect:

            In all the activities named test I had a good GPS-fix before pressing the startbutton, accuracy at or below 4m.

            There is obviously a problem with GPS-fix in the start of a recording, as others have pointed out in this thread!
            Last edited by jonas.rosengren; 05-19-2011, 12:23 PM.


            • #7
              +1 same issues here ... even if i wait until signal quality is 3/4 meters start of run is way off.


              • #8
                Today I used smart recording and hoped for better results. Start problem remains. It doesn't look that bad below but keep in mind I had perfect sat reception.

                Red dot is where I stretched a bit until sats where fixed and some extra time. Then I waited until GPS accuracy was 3/4 meters. Then ran slowly which is the red line you see. Actually started the recording/workout at the GREEN dot and ran the green line.

                Sorry for my lack of mspaint skills


                • #9
                  Went for my first run today.


                  Not a glitch on the map. A bit of drift here and there, maybe 10-20 feet, but completely in line with what my 305 did. No nasty jumps like others are reporting, even right at the start.

                  However, if you look at the pace chart, it has me starting out at 0:59 per mile, then down to over 12:00 per mile, before settling into my real pace. That's a little troubling. I never saw that in any of my 305 runs. Will keep an eye on that one.

                  But I did just remember another change. On my 305 I always used smart recording, and I set up the 610 to do 1 second recording. If I keep seeing this on 1 second recording, I'll switch over to smart and see if it still happens there.
                  Last edited by BIT101; 05-20-2011, 07:39 AM.


                  • #10
                    BIT - I never really noticed the stop error/lap error until I put the GPS accuracy as one of the functions shown on my watch while running. Now that its there I can see when it happens. It happend after miles 3,4,5,6 today on my run, but not at the start. I used smart recording today versus 1 sec recording.

                    Your activity is blocked/private so we can't analyze it anyway.


                    • #11
                      Oops. accidentally clicked the lock icon, thinking it meant lock it from editing, not make it private. Should be able to see it now.


                      • #12
                        Originally posted by BIT101 View Post
                        Oops. accidentally clicked the lock icon, thinking it meant lock it from editing, not make it private. Should be able to see it now.
                        Bit, there is a definite blip in your GPX data at the start. And a slight blip or not at mile 1 lap. The rest looks fine. Were you using 1 sec recording or smart recording.

                        You can even see it in your Garmin Connect results. I am assuming you weren't running 60 miles/hour at the start of your run?


                        • #13
                          Yes, that's what I said in my post, that I started out at 0:59 per mile. So yes, there was a blip in speed. But there were not the weird jagged lines on the map like others are seeing. The map accurately reflects where I was.

                          However, it's interesting to export the track to Google Earth. There you can see each individual data point. There are a bunch right where I started, as if I were standing almost still for a bit, then suddenly a big jump to where I was further down the street. Had I gone that far in a one second interval, yeah, I would have been travelling at 60 mph.

                          Possibly something up with the smoothing algorithm instead of or in addition to any possible GPS problems.


                          • #14
                            Bit, when I look at your GPX data I see:

                            1. Squiggles closes together at the start, then a straight line, and then a big elliptical arc that looks like the 610 has either lost itself or is over-correcting itself.

                            If you want to see if you have the problem while running, put GPS accuracy as a field on your watch. I actually did not get the problem at my start today, but only after auto-lap clicked in the middle of the run. Though it did have me going at 5 min/mile pace at the start, which I surely wasn't.

                            Were you using smart recording or 1 sec recording. I did not get as many jaggies in my GPX data when doing smart recording. Actually I got none of those little z's.


                            • #15
                              just wanted to let you guys know that i'm having an issue with the start/stop button and data freaking out after you re-start. My first run, I just did the auto-lap 1 mile and never had to stop the watch so my data was great. I just got back where I had to press stop for a few cars on a couple instances and the pace/speed data after I re-start is totally off. It's not a major deal but I just thought I'd write it here to Garmin can hopefully log it and have a look at it. Hopefully, it's something they can address with the next firmware update. Other than that small issue, the watch has been pretty great so far.