I forgot about that :) I reset my phones "A-GPS XTRA" data and it did take a lot longer to lock from a "cold start", probably not much quicker than the O-GPS1. I don't have cell location turned on on my phone but a couple of my apps that use GPS download the AGPS data on start up if Internet services are available so I guess that's a disadvantage with standalone non-networked devices like the O-GPS1. It would be nice to know if the AGPS data is retained with the batteries out or not, using rechargables I could tolerate leaving the thing with a battery inside I guess.
>From http://www.pentax2u.com/webshaper/store/viewProd.asp?pkProductItem=108 "Pentax's O-GPS1 GPS unit draws power from one AAA-sized battery, and is capable of a cold start in around 40 seconds, while a warm start takes just 5 seconds. It can determine location information at one second intervals, save GPS track information, and has a battery life of around 5-7 hours from a rechargeable NiMH battery. Maximum battery life is around 12 hours with a lithium disposable cell at around 23°C / 73°F." I will attempt to measure the on and off state currents at some stage. Cheers, On 13 September 2013 22:51, Matthew Hunt <[email protected]> wrote: > On Thu, Sep 12, 2013 at 8:14 PM, Rob Studdert <[email protected]> wrote: > >> When it works it seems pretty good but it does take an extraordinarily >> long time to lock sometimes (noticeable when the phone takes seconds) >> and it's really touch on batteries too. > > Getting a fast GPS lock depends on having up-to-date ephemeris data, > which is broadcast by the satellites. A phone is on pretty much all > the time, so it should always have up-to-date ephemeris data. (Also, a > phone could "cheat" by getting ephemeris data from cell towers or the > Internet; I'm not sure if they do that or not.) The O-GPS1 is probably > used less frequently, so it's likely not to have recent ephemeris data > at startup. It might also forget its ephemeris data when the batteries > are removed. Getting an initial fix without ephemeris data can take a > lot longer. > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- Rob Studdert (Digital Image Studio) Tel: +61-418-166-870 UTC +10 Hours Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
