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Return to GPS Problems.
See GPS for details on how to evaluate the Freerunner GPS with command line utilities.
Username | Checked outside? | External antenna? | Note | |
---|---|---|---|---|
Pthorin | Yes | No | I tried for about 40 minutes outside, I'm running om-gta02 P1-Snapshot-20080622. Did get GPS time outside, but only got lines like:
$GPGSA,A,1,,,,,,,,,,,,,99.99,99.99,99.99*30 --Pthorin 05:11, 11 July 2008 (UTC) I tried it out once again after removing the front cover and got a fix quite fast, less than five minutes. Could there be an issue with the case blocking the signals? Could the snap/latch above the antenna be a problem? | |
iandouglas | Yes | No | Spent over a half hour outdoors, the NMEA port on my Samsung Blackjack 2 found my position just fine, but also got the same 99.99,99.99,99.99*30 line as Pthorin when powering on the GPS unit, starting gpsd, then running gpspipe at the command line | |
genki | Yes | Yes | Same here. Does not get a fix without external antenna. GPS output is 99.99,99.99,99.99*30 as well | |
timo | Yes | No | Spent over a half hour outdoors in an open area without nearby buildings. Zero good fixes, no time gotten, GPS output scrolled along with same numbers for the whole time. When I played some more, very rarely I noticed that in the AZ tab a satellite blob had appeared, always at 0 degrees at the top of the picture. But still no fixes at all or anything. | |
Dummy | ? | ? |
Let's collect hints which could solve the above problems here. E.g.: How to get the best results with your internal antenna
It could be that your GPS device is functioning properly, but needs to be "coaxed" into getting an initial fix.
Finally, there is probably room for improvement in the way GPS fixes are currently obtained. GPS devices can obtain fixes at least three different ways. The least sophisticated method downloads a set of current satellite orbits by downloading frames. If part of a frame is corrupted, the GPS device must wait 30 seconds for it to be retransmitted.
A slightly more sophisticated approach uses an initial estimate of the current time and your position to obtain a lock more quickly. Finally, instead of downloading orbit and position data from the satellites, some modern GPS devices simply recalculate the information locally. Some (or all?) of these optimizations are supported by the Freerunner's GPS device, though the software installed at the factory does not seem to make use of them.
FreeRunner_GPS_antenna_repair_SOP Indicates that the problem may be bad soldering, and includes a guide to fix. This will presumably void your warranty.