Hi Robert, You are right, its the lambda divider that was discussed. Need to better understand this approach.... 74HC40103 could also do the 81 Pi-divide easily, but I tend to prefer the PICDIV concept where the controller is clocked by the signal to divide (So limited or no noise is added). AVR family could do it, as most of the instructions take only one clock. Gilles.
> Le 20 juin 2020 à 19:48, Robert LaJeunesse <[email protected]> a écrit : > > Gilles, if I read the Calosso-Rubiola paper correctly a Pi divider is pretty > much your standard square-wave producing digital divider, such as a 74163 > (for even divides). There's odd-value (3,5,7) Pi dividers shown at > https://www.theremin.us/Circuit_Library/symmetrical_digital_dividers.html. > What the Calosso-Rubiola paper promotes is the Lambda divider, which is > depicted in figure 2 of the paper. > > Bob L. > >> Sent: Friday, June 19, 2020 at 10:27 AM >> From: "Gilles Clement" <[email protected]> >> To: "Poul-Henning Kamp" <[email protected]> >> Cc: "Discussion of precise time and frequency measurement" >> <[email protected]> >> Subject: Re: [time-nuts] Frequency division by 81 >> >> Hi, >> Could you point me to a practical design example of a Pi divider ? >> >> >> Envoyé de mon iPad >> >>>> Le 19 juin 2020 à 08:56, Poul-Henning Kamp <[email protected]> a écrit : >>> >>> -------- >>> >>>> I need to divide the output of an OCXO by a factor D=81 for testing >>>> purposes. So with minimum added phase noise. >>> >>> Two stages of divide by 9 PI-dividers ? >>> >>> http://rubiola.org/pdf-articles/conference/2013-ifcs-Frequency-dividers.pdf >>> >>> -- >>> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 >>> [email protected] | TCP/IP since RFC 956 >>> FreeBSD committer | BSD since 4.3-tahoe >>> Never attribute to malice what can adequately be explained by incompetence. >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. >> > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
