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Some FreeRunner GPSs appear to be insensitive, taking a long time, or not obtaining a fix at all, even in ideal condtions.
There is an issue where the memory clock for the SD Card interferes with the internal GPS antenna GPS Problem. A software fix is well underway and first iterations of the it appear in releases of OM2007.2 on or after 7-22-2008. Either flash a version with the fixes or else please remove the SD Card while performing the test. Obtaining a fix took well under 1 minute with the card removed and also with the software fix.
There was a report of a bad solder joint between the GPS antenna connector and the FreeRunner main PCB but it is very unlikely that your FreeRunner has this situation.
This guide outlines how to gather data to help fix this problem. It's important for both those with working GPS, and those with not-working GPS to perform this test.
There may be some with marginal GPSs that appear to work, but are drastically less sensitive than the norm.
This guide assumes that you've managed to configure your FreeRunner so that you can install opkg packages from buildhost.openmoko.org/daily-feed/ , either directly through wifi or usb networking, or by downloading them to a desktop and transferring them with scp.
We need to find the average reported signal strength of phones in a similar condition.
This should be outside, with no obstructions too near the horizon. A location with nothing within 30 degrees of the horizon is adequate. The occasional sticking up building or tree is not a big issue.
The phone should be placed upright, with the screen upright in order to make the antenna (at the top of the phone) most sensitive - if placed flat on a table, it will have very poor sensitivity to half the satellites in the sky.
Could you report the following numbers.
basic networking configured. this is beyond the scope of this howto.
ssh root@192.168.0.202
opkg update
( Ignore all warnings about missing signature files, the openmoko repository haven't got any at the moment.)
then transfer to your freerunner:
wget http://buildhost.openmoko.org/daily-feed/armv4t/openmoko-agpsui_*.ipk scp openmoko-agpsui_*.ipk root@192.168.0.202:/home/root/.
opkg install openmoko-agpsui
or
opkg install openmoko-agpsui_*.ipk
test your freerunner. Charge your battery to full capacity (can't hurt), wait for a clear weather and then check out places you can visit. The ideal place is in the middle of nowhere, but the next best thing is a area with clear view of the sky and no towering foliage or buildings nearby. Nice weather is a must have because you don't want your shiny freerunner to get soaked do you?
Ideally the FR it should sit inside a (empty) ceramic cup pointing upwards for maximum coverage. Second best is to leave the freerunner with the screen facing upwards, preferably with the top of the freerunner facing northish. (Not a requirement, just trying to be scientific. ;) )
called "Openmoko AGPS UI". Run this program. The program has several interesting features. on the top left side of it's UI you can find the tabs: "Run" "SS" "AZ" "plot" "Log"
touching it_. (a large mug works well as a stand) Do not stand over it either, your blocking those precious satelite signals! ( GPS runs at ~ 1,2-1,5 Ghz, this is a weak signal with a wavelength of 20cm, now imagine godzilla (you) smashing them. )
30 minutes you get to press the "dBm" button to translate those nasty dB.Hz into goodness dBm signals. If you've gotten FFix some of the blue blue bars has a nice black thing on the bottom. And on top of screen above each bar there are two numbers, the top denoting the maximum signal you got from each satelite and the lower number the average signalstrength.
wrong or your one of those unlucky guys (gals) with a bad solder or something else that probably requires shipping the phone back to your supplier/openmoko. If you got only 3-4 satelites and had a lousy reception (say -150 to -160 dBm) you /might/ have a faulty freerunner but you should try again somewhere else at another time of the day just to make sure. If you had a lousy reception but did get a FFix, try again somewhere else to se if you can improve your record. If you on the other hand found several satelites( +5) and had quite a good reception (maybe > -145 dBm ? ) the you probably has a working phone. Now, I'm not a radio or wireless engineer, so any numbers in dBm should be taken with a grain of salt. But the main thing is that you followed the basic instruction and did a thorough scientific test! You did Science!
you to read this howto.
http://wiki.openmoko.org/wiki/Getting_Started_with_your_Neo_FreeRunner http://wiki.openmoko.org/wiki/FreeRunner_GPS_antenna_repair_SOP http://wiki.openmoko.org/wiki/USB_Networking http://en.wikipedia.org/wiki/Global_Positioning_System