I have an eTrex Vista HCx, which I like very much but which I cannot trust. I know that the problem I have with my unit has been discussed before but I haven't seen any solution so here we go again.
I sometimes bring my eTrex during my walks to see how far I have walked. I usually walk between 5 and 12 km. When I start up the unit outside my house it quickly finds a number of satellites and gives me an inaccuracy of +/- 3m and the GPS marker is placed just at the point where I am standing.
After some time, say 10 minutes to an hour of walking, the GPS starts to drift away from the track where I am walking. Typically it has contact with 8 or 9 satellites with good reception (over or just under the forth horizontal line on the satellite display), most of the vertical bars marked with a "D". In spite of that the inaccuracy is given as +/- 7m up to +/-10m. But the GPS pointer is actually pointing to a place between 10 and 100 m away from the road or walking track where I am. Blue sky, no trees over the road, good reception.
The pointer is steady and do not move around but as I said, points to a place somewhere in the woods. After 1 or 2 km it usually drifts back to track and the inaccuracy will be ok again for the rest of the walk.
It seems as it always drifts away to the left, I haven't seen it drift away to the right.
Now, if I shut down the unit and start it up again, it will find the satellites within a few seconds and now the GPS pointer is right on spot, pointing exactly at the point where I am standing. So the signals from the satellites are good, no doubt about it.
I have the latest firmware but this problem has been there during many firmware updates. My mobile phone is switched off and no power lines in sight.
When I use the unit for geocaching I have to switch it off and on every now and then to be sure the unit points to where I am. Not acceptable is it?
Does anyone know what is happening here? I really need your help.
