GS407 : 10+ satellites in view but no fix

[Michel Blanc]

Dear All,

I got my GS407 U-Blox5 GPS from DIY Drones shop yesterday.
Unfortunately, it's been running all night long close to the window and for about 1 hour outside (clear sky, horizon on 180°) : no fix.

I have plenty of satellites in view (around 10 or so), but couldn't manage to get a fix.

Here are the NMEA sentences I get :

$GPGSV,3,1,11,01,,,42,12,,,34,16,,,25,21,,,43*7C
$GPGSV,3,2,11,24,,,43,29,,,35,30,,,45,31,,,43*73
$GPGSV,3,3,11,33,,,38,37,,,40,39,,,39*72
$GPGLL,,,,,,V,N*64
$GPRMC,,V,,,,,,,,,,N*53
$GPVTG,,,,,,,,,N*30
$GPGGA,,,,,,0,00,99.99,,,,,,*48
$GPGSA,A,1,,,,,,,,,,,,,99.99,99.99,99.99*30

This says 11 sats (GPGSV,3,1,11), but no fix (GPGSA,A,1).

I know the Time To First Fix is pretty long, but it's not supposed to be *this* long, so I'm getting worried.

Does anyone has a clue ?

Thanks in advance,

M

[Peter Seddon]

The GPGSA sentence is outputting a No Fix available as well.

I would use the u-center http://www.ublox.com/en/download-center.html?task=view.download&... prog to get inside the unit and find out what is going on and reset any parameters.

Peter

[Andrus Kangro]

Hi, surprisingly, I have same issue. I got my GS407 yesterday from Sparkfun and its hanging outside currently under (cloudy) open sky and cannot get fix. It does see satellites and was able to get date/time (I use it with u-center). EM-411 on same conditions will get fix in seconds.

[Andrus Kangro]

Hi, it started to work suddenly. I updated its flash to the latest version, and shorty after that my battery died. When I replaced battery, then it started to work almost instantly.
So I suggest to make sure you see year 2009 in gps bootup messages and also I suggest to verify that gps power is ok.

[Michel Blanc]

Hey Andrus,

Same here. I installed u-center as recommended by Peter and issued an firmware upgrade. Everything is fine since then, I get 10 flying saucers inside !

Thanks for suggestions guys,

M