[time-nuts] ADEV vs MDEV

Pete Rawson peterawson at earthlink.net
Sat Feb 6 03:59:18 UTC 2010

Efforts are underway to develop a low cost DMTD apparatus with
demonstrated stability measurements of 1E-13 in 1s. It seems that
existing TI counters can reach this goal in 10s. (using MDEV estimate
or 100+s. using ADEV estimate). The question is; does the MDEV tool
provide an appropriate measure of stability in this time range, or is
the ADEV estimate a more correct answer? 

The TI performance I'm referring to is the 20-25 ps, single shot TI,
typical for theHP5370A/B, the SR620 or the CNT81/91. I have data
from my CNT81showing MDEV < 1E-13 in 10s. and I believe the
other counters behave similarly.

I would appreciate any comments or observations on this topic.
My motivation is to discover the simplest scheme for making 
stability measurements at this performance level; this is NOT
even close to the state-of-the-art, but can still be useful.

Pete Rawson

More information about the time-nuts mailing list