[time-nuts] Timepod Phase Noise Measurements and 3 corner hat

Bruce Griffiths bruce.griffiths at xtra.co.nz
Sun Aug 30 15:45:20 EDT 2015


On Sunday, August 30, 2015 05:06:38 PM James Flynn wrote:
> Martyn Smith <martyn at ...> writes:
> > MEASUREMENT TECHNIQUE
> > 
> > We have three sources close in frequency (within 1 x 10E-8 of each
> 
> other).
> 
> > Two sources are connected to the Ch0 and Ch 2 inputs of the 
timepod, the
> > unit under test to the ref input.
> > 
> > According to John, the result will be the actual phase noise of the ref
> > input, even if it is lower than the two other sources.
> > 
> > No further calculations need to be made.
> 
> The is a publication by the NPL that talks about a similar technique, but
> comes to a somewhat different conclusion.
> 
> http://publications.npl.co.uk/npl_web/pdf/mgpg68.pdf
> 
> Bottom line: it holds that the phase noise of all three sources can be
> determined if they are taken two at a time; one as ref and the other as
> the DUT.
> 
> _______________________________________________
> 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.
How can one have any faith in a paper that cant even get the 
fundamentals of resistor noise correct?
It also perpetuates the myth that Ulrich Rodhe cofounded Rodhe and 
Schwarz.
Lothar Rodhe (Ulrich's father I believe) cofounded Rodhe and Schwarz.

Bruce


More information about the time-nuts mailing list