Hi The quality of the offset signal source matters in a DMTD system. If you are using a “noisy” source you will have trouble with the data. You also will have trouble if the offset signal is correlated in some way to one of the DUT signals.
Bob > On Jan 20, 2018, at 3:43 AM, tim...@timeok.it wrote: > > > Hi Corby, > I did several tests to verify the system noise floor using the same source > for both input channels. I have seen that the result varies a lot as the > difference in time between the two channels varies. > Moreover, if I do two successive tests without changing the parameters and > the duts, the result can not be superimposed. > It may be that I make a mistake or do not take any parameter into account. > I also wonder if there is any commercial realization of the DMTD system. > Cheers, > Luciano > > > Da "time-nuts" time-nuts-boun...@febo.com > A time-nuts@febo.com > Cc > Data Thu, 18 Jan 2018 11:13:54 -0800 > Oggetto [time-nuts] Time interval measurement vs dual mixer method > Luciano, > > Not sure what you mean by "two measures made on the same DUT never > coincide". > > The plotter program takes out wraps which since your phase gain is so > large are due to happen. > > For lower Tau measurements just adjust the phase for close to equal and > run shorter plots. > > These can be spliced into the longer Tau plot. > > I routinely get repeatable plots on the same DUT with my DMTD setup. > > Careful setup and understanding what you can and cannot accomplish is the > key. > > Cheers, > > Corby > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
