The fact that one thing is phase-locked to another does not necessarily
mean it puts out a good, clean signal. At short time scales (tau less than
~100 seconds), the PPS signal from any GPS receiver is noisy. At tau =
1second, it is shockingly noisy (~5e-9), and it decreases by a nominal
factor of 10 per decade as the averaging time (tau) is made longer. By tau
= 1000 seconds, it is pretty respectable (~2e-12 if the GPS rx designers
did their job well).
and then there are hanging bridges. :)
--
These are my opinions. I hate spam.
csteinmetz@yandex.com said:
> The fact that one thing is phase-locked to another does not necessarily
> mean it puts out a good, clean signal. At short time scales (tau less than
> ~100 seconds), the PPS signal from any GPS receiver is noisy. At tau =
> 1second, it is shockingly noisy (~5e-9), and it decreases by a nominal
> factor of 10 per decade as the averaging time (tau) is made longer. By tau
> = 1000 seconds, it is pretty respectable (~2e-12 if the GPS rx designers
> did their job well).
and then there are hanging bridges. :)
--
These are my opinions. I hate spam.
