> The time stuff I understand, even the radio wave propogation stuff, > though obviously not as well as others here. > I'm not sure what "cable length", "speed of light delay", or "velocity > factor" is all about. >
What I was getting at was that that better GPS receivers are so accurate with their pulse per second that you have to carefully account for the delay in a short cable. In other words the delay due to speed of light down a wire that is four feet long is greater then the error in the PPS. I brought it up to show how insanely small the timing error is. Then "velocity factor" is a correction the signal does not move a speed of light in a real wire. None of this matters for NTP. But some people use GPS for other purposes, like maintaining a frequency standard. or running cell phone towers. NTP is actually one of the least demanding uses of GPS timing signals -- Chris Albertson Redondo Beach, California _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
