[time-nuts] Disciplining Rubidium
jmiles at pop.net
Thu Apr 24 02:04:12 EDT 2008
> The actual FRS-C is quite a bit cleaner but still nowhere near as good as
> the Thunderbolt.
> Also worth noting is that the Datum's output is quite a bit
> noisier than it
> was several months ago when I measured it with (very) different
> hardware. I
> wouldn't take the green trace in this graph to the bank until I've had a
> chance to repro that earlier measurement. Still, either way, it's
> definitely much noisier than the Thunderbolt.
My mistake - there's no meaningful difference, it's within 2 dB of my
earlier measurement on the 11729C. I think I was confusing that trace with
the FSC-C rubidum measured by itself, which is good for a floor between -135
and -140 dBc/Hz.
-- john, KE5FX
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