Sorry I was under the impression I was replying to Don's post. Sometimes my Windows machine seems to mess up the part of the thread to which I thought I was replying. My Linux box doesn't seem to have this problem.
Bruce On Tuesday, January 05, 2016 09:26:14 PM Charles Steinmetz wrote: > Bruce wrote: > >You mean DMTD = dual mixer time differencenotDDMTD = Digital dual > >mixer timer difference.The latter uses a pair of synchronisers / > >shift registers instead of a pair of mixers. > > I don't see how your comment is relevant to my post -- I did not > mention either DMTDs or DDMTDs. I only noted that the AD835 is > noisier than a diode mixer, although not as noisy as many analog > multipliers -- and that some noise improvement has been demonstrated > by using parallel multipliers. > > Charles > > >On Wednesday, 6 January 2016 12:03 PM, Charles Steinmetz > > > ><csteinm...@yandex.com> wrote: > > Poul-Henning wrote: > > >My little HP5065 project is continually running into the jitter of > > >my HP5370B counter which is annoying me, so I'm looking int DMTD. > > > > > >Everybody seems to be using traditional diode-mixers for DMTD, > > >and to be honest I fail to see the attraction. > > > > > >Why wouldn't a analog multiplier like AD835 be better idea ? > > > > > >What am I overlooking ? > > > >You could have mentioned any of dozens of popular analog multipliers, > >and the answer would have been, "because they are way too > >noisy." The AD835 is also substantially noisier than diode mixers, > >but it at least begins to bridge the gap. The folks at CERN have > >been improving phase detector S/N by averaging the output of several > >AD835s for the TPMON project, with promising results. There is a > >preliminary report in "EUROTeV Report 2006-005-1." > > > >See also: > > > >RF-based electron beam timing measurement with sub-10fs resolution, > >A. Andersson and J. P. H. Sladen, CERN (EUROTeV Report 2008-015) > >[phase detector with 8x AD835 analog multipliers]. > > > >ANDERSSON, A. and SLADEN, J. P. H.: "First tests of a precision beam > >phase measurement system in CTF3" (Proc. PAC07). > > > >"PRECISION BEAM TIMING MEASUREMENT SYSTEM FOR CLIC SYNCHRONIZATION," > >A. Andersson, J. P. H. Sladen, CERN (Proceedings of EPAC 2006). > > > >Best regards, > > > >Charles > > _______________________________________________ > 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.