[time-nuts] Cross-Correlation Results
azelio.boriani at screen.it
Sat Aug 4 23:31:40 UTC 2012
In your opinion, how the Wenzel company got the data for the ULN
On Sat, Aug 4, 2012 at 11:02 PM, Bruce Griffiths <bruce.griffiths at xtra.co.nz
> John Ackermann N8UR wrote:
>> Magnus inspired me to try my own cross-correlation experiment with the
>> TimePod today. I used two fairly normal OCXO frequency standards as the
>> reference, and a Wenzel 5 MHz ULN as the device under test.
>> By doing single-reference measurements of each OCXO versus the ULN, I was
>> able to plot their noise. Since the ULN has performance near the noise
>> floor of the TimePod, I could then test how well the correlation works to
>> allow measurements below the noise of either reference.
>> Conclusion: it works *really* well. Plots and a little write-up are at:
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to
>> and follow the instructions there.
>> Even a pair of Trimble 34310T ocxos appear to work well as the dual
> reference oscillators.
> If one could use a pair of ocxos to drive the other pair of ADCs it should
> be possible to evaluate the contribution of the Timepod itself to the noise
> Using an interferometric technique with a Timepod allows a PN noise floor
> of -200dBc/Hz or less to be achieved (with a test source noise floor of
> around -175dBc/Hz or worse) when measuring the additive PN of components
> such as amplifiers.
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> and follow the instructions there.
More information about the Time-nuts_lists.febo.com