Last night I noticed some very strange GPS behavior for the first time in the 5+ years of my RTCM voter system’s operation.
1.Two of the sites’ RTCMs kept losing GPS lock, with the “GPS Data time period elapsed” message at the console. Upon looking at some GPS debug data, I noticed that the GPS would promptly reestablish connection with 9-10+ satellites after this message. Nothing has changed at either of these sites RF wise. It is also interesting to note that these sites are less than a 1/4 mile apart from each other.
Note that I am using the Garmin 18X LVC pucks at 4800 baud, where the ASL wiki says I should use them at 9600 if I get this error message. What’s interesting though, is they’ve been 4800 for years and I’ve never noticed this issue before until last night. Looking at the debug console again today, I am not seeing any of “GPS Data time period elapsed” at either site at all. It’s peculiar that two of my three identical sites would exhibit this problem at the same time out of the blue, so I thought I was worth sharing and seeing if anyone had any ideas.
- Looking at my third site’s RTCM GPS debug, I was seeing no “GPS Data time period elapsed” whatsoever, but I did notice something very bizarre.
GPS-DEBUG: mon: 2, gps_time: 953153551, ctime: Wed Mar 15 20:52:31 2000
Restarting the RTCM, turning off and on the GPS would not fix it. Do we suspect a bad puck? This site is identical to the other two, same Garmin puck in same configuration.
Any ideas on either issue would be appreciated. I do plan to change all three pucks to 9600 baud, but again after 5+ years I’ve never had the “GPS Data time period elapsed” error until last night.