[time-nuts] GPS-18x behaving weirdly
I've got some GPS-18x LVC units i'm using for a time reference, and they're showing an odd behavior: the position isn't updating. I moved them across the US (from Los Angeles to the east coast), and when I powered them up here, it's returning the LA Lat/Lon (34N,118W), the (reasonably correct) UTC time and date, but never getting a fix. In theory, this should be like a cold start, and in 45 seconds, it should reacquire the satellites it can see from scratch, but it's not. I got one to start going by running the Garmin configuration program and setting the current position (not all that accurately, within 1 degree lat/lon), and it started running. The other doesn't seem to want to come alive. I'm assuming that it's just running the clock forward based on it's internal low power clock/battery. I haven't checked for the 1pps output (no scope here, for one thing..and I'm not quite ready to write some software to probe the RS232 pins to see if it's there. Has anyone seen a similar behavior? I've tried the power cycling, and the Garmin reset command. I've not done the clear non-volatile memory which makes it forget the almanac. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS-18x behaving weirdly
From: Jim Lux [] Has anyone seen a similar behavior? I've tried the power cycling, and the Garmin reset command. I've not done the clear non-volatile memory which makes it forget the almanac. === What firmware are those units running? Is it the latest? 3.90? Maybe blowing the firmware would reset the position? Otherwise, I do have a simple program for monitoring the serial port: http://www.satsignal.eu/software/net.htm#SerialPortLEDs Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS-18x behaving weirdly
jim...@earthlink.net said: Has anyone seen a similar behavior? I've tried the power cycling, and the Garmin reset command. I've not done the clear non-volatile memory which makes it forget the almanac. I had one GPS-18x LVC go insane. I don't remember the details. I think it didn't say anything as compared to saying things that didn't make sense. I tried to take it apart, but never got very far. After a month or two, the battery ran down and it started working again. Since you have nothing to loose, I'd leave it running to see if it recovers. If anybody figures out how to update the firmware from a non-Windows environment, please let me/us know. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS-18x behaving weirdly
On 3/27/14 8:53 AM, David J Taylor wrote: From: Jim Lux [] Has anyone seen a similar behavior? I've tried the power cycling, and the Garmin reset command. I've not done the clear non-volatile memory which makes it forget the almanac. === What firmware are those units running? Is it the latest? 3.90? Maybe blowing the firmware would reset the position? yes, running 3.90.. they're only a year old, and 3.90 came out earlier than that I think.. In any case, I set one of them to the present lat lon, within a few seconds of arc, and it seems to have acquired, changed the fix a bit, and then stopped again. The other one is resolutely stuck. I'm thinking there's got to be some simple option that I'm overlooking. It's kind of frustrating, because there's no NMEA sentence that tells you what the acquisition/search status is: just which ones it is trying to track and what the status is (unlocked, no data for all of them). Otherwise, I do have a simple program for monitoring the serial port: http://www.satsignal.eu/software/net.htm#SerialPortLEDs I'll try that.. Cheers, David ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS-18x behaving weirdly
Not sure that I can help much. I have been following the thread and have numbers of units of this vintage and have used a few in projects. Those projects seemed to have funnies after a while. I am starting to have a bad feeling that if I look carefully I will find some of this perhaps going on. However if I go back into those projects at all I suspect I will shove a ublox in and be done. One was the TrueTime GOES DC468 sat simulator. Thanks for an idea. Regards Paul WB8TSL On Thu, Mar 27, 2014 at 6:56 PM, Jim Lux jim...@earthlink.net wrote: On 3/27/14 8:53 AM, David J Taylor wrote: From: Jim Lux [] Has anyone seen a similar behavior? I've tried the power cycling, and the Garmin reset command. I've not done the clear non-volatile memory which makes it forget the almanac. === What firmware are those units running? Is it the latest? 3.90? Maybe blowing the firmware would reset the position? yes, running 3.90.. they're only a year old, and 3.90 came out earlier than that I think.. In any case, I set one of them to the present lat lon, within a few seconds of arc, and it seems to have acquired, changed the fix a bit, and then stopped again. The other one is resolutely stuck. I'm thinking there's got to be some simple option that I'm overlooking. It's kind of frustrating, because there's no NMEA sentence that tells you what the acquisition/search status is: just which ones it is trying to track and what the status is (unlocked, no data for all of them). Otherwise, I do have a simple program for monitoring the serial port: http://www.satsignal.eu/software/net.htm#SerialPortLEDs I'll try that.. Cheers, David ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
