> * Two years ago I bult my own GPS frequency standard based on the design by > James Miller but it has been a big disappointment. I started to suspect it > was not reliable so I wrote a LabView program to compare it to the reference > outputs of two ArgoSystems AS210 systems I found on eBay and restored. The > LabView program confirmed my suspicions that the GPS receiver was briefly > loosing its stability for brief periods several times a week. The AS210s > tracked each other reliably and extremely closely. I have not gotten to the > bottom of the problem with the GPS receiver yet.
Hi Dennis, Welcome to the group. Yes, that does sound like a GPS receiver board or even antenna problem. I can loan you a working GPS 1PPS source if it would help you debug. My guess is it's not a problem with the James Miller design. Which version are you using?. I tested one of his GPSDO recently and was amazed at the performance. Remember his designs are really *simple* (no microprocessor, no time interval counter, no fancy DAC, no voltage reference), yet the performance is quite amazing. See his latest: http://www.jrmiller.demon.co.uk/projects/ministd/frqstd.htm http://www.jrmiller.demon.co.uk/projects/ministd/stab.htm /tvb _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
