Joseph Gwinn wrote: > In article <[EMAIL PROTECTED]>, > Uwe Klein <[EMAIL PROTECTED]> wrote: > > >>Joseph Gwinn wrote: >> >>>I may need a Dual Mixer Time Difference (DMTD) instrument, to measure >>>picosecond changes in electrical length in a coax plus amplifier time >>>reference signal distribution system with total delays in the hundreds >>>of nanoseconds, currently operating at 10 MHz (sinewave), but with 100 >>>MHz likely at some future date. >>> >>>What DMTD instruments are commercially available? A google search was >>>not successful - all noise no detectable signal, probably because DMTD >>>instruments are not that common, and many people build their own. >>> >>>Thanks, >>> >>>Joe Gwinn >> >>Take one of the "better" GS DSO's that have high storage depth. >>Read the shots from the DSO and do all further processing in software? > > > I don't understand how this would work. Could you expand the > description? And what is "GS"? GS as in GigaSample > http://www.unusualresearch.com/AppNotes/TimeNuts/OptDualMixer.pdf http://www.wriley.com/paper6ht.htm
if my understanding is correct: take a large syncronous sampling of both signals. extract the data. retrace in software the math done in hardware on the aquired data set. i.e. if you do a soft mixdown to DC you should get two vectors (R/I) describing the phase relationship between both signals. uwe _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
