Hi Didier: Been surfing your Timing web page and came across http://www.ko4bb.com/Timing/FrequencyReference.html Got there by working up the URL for the Vig paper.
An ordered list of Time Transfer methods from carrier phase GPS to the Astrolabe is at: http://www.prc68.com/I/timefreq.shtml#TT that ranks HF time stations far below other methods, so although they can be used there may be better choices that are affordable. Also for GPS timing applications (i.e. the GPS receiver is in position hold mode) a single satellite is all that's needed. Adding more satellites can add a failure alarm function but may not improve accuracy. In my case multipath is a big problem so a high elevation mask is needed. The problem with a less than 12 channel receiver relates to how satellites are selected. The Motorola timing receivers will continue to track a satellite until it sets rather than switch to a a new one which may be directly overhead. The "use highest in the sky" applies to how a new satellite is selected. Once selected the satellite is tracked until it sets. An idea: When averaging GPS 1 PPS signals the receiver switches satellites as the currently tracked ones set so there may be a slight change in accuracy because of the satellites being used. But changing from a satellite that's about to set i.e. that has a lot of multipath to high in the sky sat should make for a better 1 PPS. -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.precisionclock.com http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Cam _______________________________________________ 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.
