Hi But would you cryo cool the walls of the fountain enclosure? It helps …..
Bob On Dec 4, 2012, at 9:46 AM, Bill Dailey <docdai...@gmail.com> wrote: > Agreed and they probably wouldn't use a cryogenic sapphire oscillator. > > Sent from mobile > > On Dec 4, 2012, at 8:34 AM, "Bob Camp" <li...@rtty.us> wrote: > >> Hi >> >> Indeed, you likely won't get USNO grade with a shoe box sized part. You can >> get one to work and do quite good ADEV. No, I haven't done it, I'm just >> going on what I've been told. The main point being that for a basement >> project - smaller is probably lower cost. >> >> Bob >> >> -----Original Message----- >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >> Behalf Of Poul-Henning Kamp >> Sent: Tuesday, December 04, 2012 9:19 AM >> To: Discussion of precise time and frequency measurement; Bill Dailey >> Subject: Re: [time-nuts] PTTI 2012, part 2 >> >> -------- >> In message >> <CAMPhiorJihW9z6-q0+Qfd+GPLjs6e8_ovWrDxQoxV=92hgj...@mail.gmail.com> >> , Bill Dailey writes: >> >>> If you look at the papers on portable rubidium fountains >>> they are significantly bigger than a shoebox (65 cm). >> >> Diameter is controlled by dispersion of the launched atoms (=recovery rate) >> and the layers of shielding. >> >> 65cm looked like close to a minimum for USNO grade, amateurs could probably >> make do with less shielding. >> >> -- >> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 >> p...@freebsd.org | 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 -- 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. _______________________________________________ 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.