Dear all, I worked on low-noise regenerative dividers long time ago. See my home page http://rubiola.org , click on "more journal articles"
22. E. Rubiola, M. Olivier, J. Groslambert, Phase noise in the regenerative frequency dividers (PDF, 670 kB), IEEE Transact. Instrum. Meas. vol.41 no.3 pp.353-360, June 1992. ©IEEE. Notice that you can divide by 4 with a single divider, using the 3rd harmonics internally generated by the double balanced mixer. Dividing 80 MHz, you feed a 20 MHz back to the mixer. A 60 MHz signal is generated by the mixer. 80 MHz - 60 MHz = 20 MHz, here you go. Another issue is the correction of the phase noise of a digital divider using a double-balanced mixer. Read this *smart* article D. Huffman, Extremely low noise frequency divider, Microwave Journal November 1985, pp. 209--210 Very best, Enrico On 29 Sep 2007, at 3:02 , John Miles wrote: > Submitted for general discussion: I have a need to divide a low- > noise 80-MHz > clock by two, twice, to obtain 40 MHz and 20 MHz outputs, and my > current > thinking is that the quietest way to do this is with a pair of > cascaded > regenerative dividers. Does anyone have any 'favorite' papers or > application notes on regenerative divider design/construction? > > In particular, what considerations go into determining the > bandwidth of the > post-mixer filter, and how important is the phase-shift network > often seen > in the feedback path? My overriding concern here is phase-noise > performance. > > -- john, KE5FX > > > > _______________________________________________ > 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. Enrico Rubiola professor of electronics web: http://rubiola.org e-mail: [EMAIL PROTECTED] FEMTO-ST Institute 32 av. de l'Observatoire 25044 Besancon, FRANCE voice: +33(0)381.853940 (E.Rubiola) voice: +33(0)381.853999 (switchboard) fax: +33(0)381.853998 _______________________________________________ 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.