Hi
> On Dec 9, 2015, at 12:34 PM, Tom Van Baak <[email protected]> wrote: > >> Are you aware of some redeeming value that phase microsteppers >> have that would make us want to investigate them? Am I >> being too harsh on them? Maybe you can champion them and they >> will make a come back :-) >> >> Rick Karlquist N6RK > > A phase microstepper is useful with many older Rb and Cs standards (e.g., > 5061A and 5065A) so that you don't have to touch the C-field. It is also > useful with a 5071A to improve the time sync/step/steer resolution. > > Note that you can also implement a GPSDO with a phase microstepper and this > allows you to avoid Vref, DAC and EFC. Not all LO have EFC, and even if they > do, it may be more stable not to use EFC. Plus with a DDS you avoid > EFC-out-of-range problems. > > See also http://leapsecond.com/pages/fe405/ and the links near the bottom. > This (patented) FEI design avoids the spur issues several of you have been > talking about: the RF output comes from a low-noise VCXO not the low-drift > OCXO+DDS itself. > It avoids the far removed spurs. If you have a close in spur, it passes right through the PLL loop and messes up your ADEV. Yes, this really does happen on real gear in the real world ….. Bob > And finally, another very interesting use of a DDS as a sort of microstepper > phase comparator is: > http://www.ptfinc.com/dsheets/App_35_picoPak.pdf > > /tvb > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
