Tom Van Baak wrote: > 6a > > >> I used a 100k sample average which yields (IIRC) 200 femtosecond >> resolution in the 5370B, and for each run checked the min, max, and >> standard deviation statistics to make sure nothing goofy was going on >> Standard deviation for a run like that on my 5370B is typically 30 to 40ps. >> >> John >> > > 30-40 ps seems OK to me. But are you saying then that you > get a measured value to 200 fs resolution but with +/- 30 ps > standard deviation? This doesn't feel right at all. It seems to me > if your sdev is +/- 30 ps it is incorrect to even write down the > measured values to ps levels; and fs are out of the question. > > / > > > _______________________________________________ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > Tom
I assume the standard deviation is that of the population of 100K measurements and not the standard deviation of their mean, which should be around 95-126 fs. Averaging of course does nothing to reduce systematic errors which can be as high as 100ps in a 5370A/B. However for cable matching purposes systematic errors largely cancel out. Bruce _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
