If you use the DIYDrones MediaTek GPS, you're probably aware of the fact that, on each activation, it make take a very long time to get proper satellite lock. The reason is that it always starts from scratch; it is not aware of it approximate geographic location, not of the time.
The reason for this is lack of backup battery. Data is completely erased once you disconnect the main battery.
The GPS module itself has a backup battery input. I added a new Wiki page to the ArduPirates Wiki that shows how to connect an external battery to that input.
http://code.google.com/p/ardupirates...backup_battery (link fixed)
early versions of Mediatek GPS had a backup battery, they was removed because it made ist "unstable"
I don't know how this affects the lock or something, i never had one
So i might think about doing this, however your link doenst work...how long have you been using this without any issues?
(edit by moderator: link fixed)
Bumping an old thread, but... Dror, how is this mod holding up for you? Notice any ill effects?
This is indeed old history. It did not work well, it failed to lock most of the time. I believe the ACM (at that time, ArduPirates s/w) had problems synchronizing with the GPS module but I don't really know, I had no chance to really debug this, as I lost my quad a short time after that.