GPS

[Ole Kliemann]

On Sat, Jul 12, 2008 at 08:11:45PM +0800, William Kenworthy wrote:
> Does it make any difference to leave the gps running 15 minutes plus
> (probably a few multiples of 15 minutes is best) then power off for a
> few minutes and then back on?
> 
> My freerunner isnt here yet, but my experience on a cheap bluetooth gps
> that I though just had occasional conniptions was actually operating
> according to design
> 
> On the first fix (or a fix after a few weeks on the shelf powered off),
> it would take some time (once being over a day with poor signal) to get
> a fix, after which it would be fine getting a nearly instant fix on
> startup.
> 
> Turns out the device needs information downloaded from a satellite and
> can take ~13 minutes to do so.  And at least one article mentioned that
> any problem/lost/corrupted data caused it to start again at the next
> start point.  So if you have a poor signal, something blocks it at a
> critical point, you can scratch that 15 minutes.
> 
> As the freerunner has come straight from the factory, probably with none
> of this data, it will need at least 15 minutes with a good signal to get
> its data up to date.  This data is also valid for 6 weeks which explains
> the erratic operation after extended periods of non-use of my bluetooth
> unit.
> 
> Learnt a lot reading up on this :)
> A good thread!
> BillK

Funny... my experience has been completely contrary to this. When I
first tried GPS, it got a fix within minutes at the open window.

I then installed gpsdrive and did some other stuff. I did not get a fix
anymore. I undid the software changes by starting from a fresh reflash.
But i never got a fix again.

Today I tried outside 15min with antenna faced skywards. agpsui signal
strength display did not show any activity.

Don't know it made it work the very first time. 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 197 bytes
Desc: not available
Url : http://lists.openmoko.org/pipermail/community/attachments/20080712/0c6f245b/attachment.pgp