[time-nuts] Reference oscillator requirements when measuring ADEV ?
Bob Camp
lists at rtty.us
Fri Jul 15 01:05:06 UTC 2011
Hi
You can be quite sure it's no worse than 2x10^-12. It is pretty common to scale by square root of two based on a "they could be equal" assumption.
Bob
On Jul 14, 2011, at 8:32 PM, Mark Spencer <mspencer12345 at yahoo.ca> wrote:
>
>
> I'm curious in knowing if there are any rules of thumb as to how much better a
> reference oscillator needs to be than the device under test when measuring ADEV
> ?
>
> To provide a bit of context to my question I'm using a HP 5370B to repeatedly
> measure the time interval between the 10 Mhz signals from a FTS 1050 and
> rubidium oscillator.
>
>
> Having compared the FTS 1050 to another OCXO in the past I'm confident that it
> is meeting or exceeding it's spec of an ADEV of 1X10-12 or better at tau's of
> say 100 thru 1000 seconds. I'm also confident that at tau's of 100 seconds or
> more the noise introduced by the 5370B is less than 1x10-12.
>
> The underlying question that I have is how much confidence could I put in
> measurements that show the rubidium of having an ADEV of say less than 2.0X10-12
> at a tau of 100 sec ?
>
>
> This is just for a hobby (: and I'm not looking for any degree of certainty but
> I'm curious in understanding how accurate the measurements might be and if
> changes in the measurements might not be caused by changes in the device under
> test.
>
> Thanks in advance for any replies.
>
> Regards
> Mark Spencer
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
More information about the Time-nuts_lists.febo.com
mailing list