[time-nuts] Z3801 lockin behaviour

[Tom Van Baak]

> The end goal is to compare the Cs, Rb and GPS at various time constants,
in
> which case I will be able to resolve the phase-noise of each of them.
>
> Right now I'd say I only have a solid 9 digits.
>
> Cheers,
> Magnus

My gut tells me only 9 digits means something is quite
wrong. All HP GPSDO I've tested, free-running or locked,
have stabilities better than 1e-11 at 1 second. See:
http://www.leapsecond.com/pages/z3801a-osc/

But before you jump into debugging your Z3801A are
you sure your Cs ref and counter setup is working
right? Do you have any other 10 MHz source you
can use to independently validate your measurement
system? What is your gate time? Do you see the
same noise in the 1PPS output?

/tvb