David Rysdam <da...@rysdam.org> writes: > On 05/12/2010 01:46 PM, Joshua Judson Rosen wrote: > > > > This is why I'm dubious of these `N810's GPS receiver is slow' claims-- > > because coupling them with `... so I never use it' is actually a > > vicious cycle. > > Are the claims peculiar to the N810? If not, perhaps you are right. > What other not-always-on-the-internet devices that support GPS as a > non-main feature are there? > > I could do a test. Get a fix, drop it, wait N hours and reacquire. > Graph reacquisition time against N. Except I'll never have the time for > all those tests, so I'll just do one if you suggest a value for N.
Well, the way I interpreted your described use-pattern put N somewhere in the thousands. ;) My suggestion is to duplicate the ranges of N described in this here page that I found: http://www.pocketgpsworld.com/ttffcomparisons.php ... noting that "between 8 to 12 hours" means that you want to have had a successful fix *within the past 12 hours*; and that you want to be sure that you actually wait for a `3-D fix', because you can get a 2-D fix before you have enough data to get a 3-D fix, and some elements such as GPS time can become available without having attained fix. Summary: Cold tests were performed when both Pocket PC and GPS receiver were powered off (if GPS receiver has a separate power source, the GPS receiver was unplugged) for a period of between 8 to 12 hours requiring a cold start. Warm tests Warm tests were performed when both Pocket PC and GPS receiver were powered off (if GPS receiver has a separate power source, the GPS receiver was unplugged) for a period of 30 minutes Hot tests Hot tests were performed when both Pocket PC and GPS receiver were powered off (if GPS receiver has a separate power source, the GPS receiver was unplugged) for a period of 15 minutes And, of course: be sure that you are outdoors with a clear sky, and that you have a nice wide view of that sky. It'd probably be worthwhile to take note of both the `2-D fix' time and the `3-D fix' time, and the length of their delta. > I will note, though, that when I first unpacked my actual GPS it > acquired a signal in just a couple of minutes *from inside the house* > whereas the N810 has rarely done it even standing in the yard for > significant fractions of an hour. Pshaw--I bet that's another trick: they probably preprogrammed it with your shipping-/billing-address, just to make themselves look better ;) -- "Don't be afraid to ask (λf.((λx.xx) (λr.f(rr))))." _______________________________________________ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/