Didier Juges wrote: > Dr Bruce Griffiths wrote: > >> Didier Juges wrote: >> >> >>> Sorry, it's not 15nS rms, it's 15nS at 1 sigma. >>> >>> Didier KO4BB >>> >>> >>> >> Didier >> >> Surely the standard deviation (1 sigma) and the rms values are identical? >> Specifying 1 sigma is perhaps intended to signify that the timing error >> is stochastic. >> >> Bruce >> >> > Bruce, > > Not knowing how it is measured and the nature of the noise, I realized I > had *assumed* rms and 1 sigma to be the same, but in fact I was not sure. > The data sheet does say "at 1 sigma", so I wanted to be accurate and not > make assumptions, this is time-nuts after all :-) > > Let's be honest, if I had not corrected myself, you would probably have > commented, and rightfully so, that the data sheet actually said "at 1 > sigma" :-) > > I am trying to learn, I am just a little slow... > > Didier > Didier
Oops, if however the error has a non zero mean then the rms and 1 sigma values are not identical. Such a systematic offset can arise from antenna, receiver and cable delay Bruce _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
