[time-nuts] PTTI 2012, part 2
Poul-Henning Kamp
phk at phk.freebsd.dk
Tue Dec 4 14:18:46 UTC 2012
--------
In message <CAMPhiorJihW9z6-q0+Qfd+GPLjs6e8_ovWrDxQoxV=92Hgjo8A at 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
phk at 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.
More information about the time-nuts
mailing list