[time-nuts] Data Collection for Allan Deviation

[Poul-Henning Kamp]

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In message <1925117252.232793.1438455428192.JavaMail.yahoo at mail.yahoo.com>, Bob Stewart writes:
>Hi Poul,

>"0)  Make sure that the counter does not get its reference frequency
>    from any of the input signals."
>
>Does your rule 0 hold if one of the input signals is a Cs standard? 
>I believe I've posted in the past that the ADEV from 1 tau to 100
>tau is a bit noisy if I use the internal 10811 to clock the 5370A. 
>I noticed the same on my 5335A.

For me it is a rule of principle:  If the HP5370 is clocked from the
same source I'm measuring, I can have no expectation of a well
behaved noise from the triggers.

The "noise" you saw is probably exactly that:  Overly optimistic
results if you clock the counter from one of the DUTs

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