[ANSS-netops] RT-130 GPS issue

[Dave Drobeck]

Hi All,
I'm having a mysterious problem w/ one station.   It had been working 
fine for ~ 8 years, then recently the GPS clock stopped locking.  I 
visited the site with complete replacement parts (DAS, GPS, cable).  I 
finally got it to work w/ different DAS and original cable and GPS 
clock, but it turned out that that was the last time it locked.  On-site 
what I observed is that if I told the clock to go continuous it would 
turn on, search, say it locked but reported 0 SVs, then turn off w/o 
syncing the RTC.  After much fooling around and trial and error with GPS 
mode, cables, DAS, clocks, I got the different DAS and original clock to 
to behave, locked, reported 8 SVs, synced RTC, looked good.  Went home. 
  Hasn't locked since.  Same behavior, I can turn the clock on via RTCC, 
but the DAS reports it turns off again immediately w/o syncing the RTC.

The "good" news is I have reproduced the behavior in my shop, so I can 
work here, but I haven't figured it out yet.  Has anyone else had this 
problem - and a solution?  Thanks,
Dave