[time-nuts] ADEV computed, now what?

[Bob Stewart]

I think I have the unwrapping and scaling sorted out, so here's the result for 1PPS vs 10MHz for my GPSDO, as measured by a 5334B clocked by the same 10MHz.    I don't know how to read these, but 6,3,1,6,3,1 etc. doesn't look normal.  I wonder if that merely reflects the consumer grade GPS receiver I'm using (Adafruit Ultimate Breakout), rather than a reflection on the ultimate result?  I can link to a plot of the 1PPS vs 10MHz if that's wanted.


Any comments appreciated.


** Sampling period: 1 s
** Phase data scale factor: 1.000e-09
** Total phase samples: 86399
** Normal and Overlapping Allan deviation:

       1 tau, 6.1669e-09 adev(n=86397),     6.1669e-09 oadev(n=86397)
       2 tau, 3.2413e-09 adev(n=43198),     3.2349e-09 oadev(n=86395)
       5 tau, 1.2603e-09 adev(n=17278),     1.2470e-09 oadev(n=86389)
      10 tau, 6.0606e-10 adev(n=8638),      5.9837e-10 oadev(n=86379)
      20 tau, 3.1173e-10 adev(n=4318),      3.0967e-10 oadev(n=86359)
      50 tau, 1.2778e-10 adev(n=1726),      1.2618e-10 oadev(n=86299)
     100 tau, 6.2970e-11 adev(n=862),       6.3607e-11 oadev(n=86199)
     200 tau, 3.6391e-11 adev(n=430),       3.2994e-11 oadev(n=85999)
     500 tau, 1.4055e-11 adev(n=171),       1.4008e-11 oadev(n=85399)
    1000 tau, 8.4596e-12 adev(n=85),        7.8291e-12 oadev(n=84399)
    2000 tau, 4.8688e-12 adev(n=42),        5.0306e-12 oadev(n=82399)
    5000 tau, 3.7358e-12 adev(n=16),        4.1679e-12 oadev(n=76399)
   10000 tau, 3.7403e-12 adev(n=7),         3.5550e-12 oadev(n=66399)
   20000 tau, 1.9271e-12 adev(n=3),         2.6676e-12 oadev(n=46399)