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See GPS for details on how to evaluate the Neo FreeRunner GPS with command line utilities.
It was found that the Openmoko FreeRunner GPS has a long Time To First Fix (TTFF) when there is an SD card in the phone. This thread indicates that there is interference from the SD card slot: TTFF is much shorter without an inserted SD card.
NOTE: It seems that in the newer version of the hardware, a compensating capacitor is now present. So this problem should be fixed with newer devices. First noticed on 20080724 and confirmed on 20080830. You can check if it has the fix by looking for the capacitor beneath the SD card, as shown in this PDF file. |
A software workaround has been released as a kernel patch and may be acquired simply by doing an "opkg update" and "opkg upgrade" and then rebooting your FreeRunner. This workaround effectively turns off the SD card clock when the SD card is not being used. One will be able to use the SD card at the same time as the GPS except for the first approximately 30 seconds.
Openmoko is soliciting the assistance of the community to test the effectiveness of this software fix. The experiment consists of a series of measurements in different conditions, prior to applying the software fix and then after applying the software fix. Please visit FreeRunner GPS Software Fix TTFF Measurement Test for instructions to participate and to see the results so far of this test.
Openmoko has examined a hardware solution: soldering a 10 pf capacitor between SD card pin 5 (clk) and pin 6 (Vss) File:Gta02 gps 10pf rework sop.pdf and more detailed File:SOP for GPS capacitor rework.pdf. This effectively restores GPS performance to the levels obtained without the SD card inside. The rework is not suggested to end users without hardware soldering technique and equipment. This rework is done on all the new fabricated Neo FreeRunners
Openmoko
See:
The following is based on Alasal's post to the community mailing list.
Also note that there is a trac ticket for this issue: #1542
FreeRunner_GPS_antenna_repair_SOP Indicates that some (rare?) units may have bad soldering, and includes a guide to fix. This will presumably void your warranty.