[time-nuts] DMTD, TimeLab and Agilent 53132 Counter

[Jorge Gomez]

Hi All,

I am trying to use the DMTD method to measuring a very stable 10MHz Double
Oven OCXO against a HP Z3805, The Counter is measuring in Time interval
mode, The offset lo signals to the mixers are 10MHz+10Hz from another OCXO.
The measured time difference is anywhere  from 0 to 0.1 second until it
wraps.

The Timelab  settings are:

Sampling interval = 0.1s (auto set by the incoming data monitor when TD is
~0.05s)
Input frequency =  10MHz
Scale factor =  1E-6


The system seems to work fine when the time difference is small but when
the time difference read by the 53131 counter approaches ~0.078s I see a
slow down on the measurements rate to about 0.2 measurements/s, and a jump
on the TimeLab ADEV plotted results of about one order of magnitude

Have anyone experienced something similar? any advice on the settings?


Thanks in advance,
Jorge.