[time-nuts] Re: Video of early Cesium clock development

[paul swed]

Tom
I remember the pictures of the unit. But perhaps did not realize that you
actually purchased or own the unit? Now that would be one heck of a job to
clean up. Would guess the C's are very very long gone. Although the
video sent was interesting to see how they just dumped the Cs capsule in.
It looked like a plunger mechanism to break the capsule. Maybe a
solenoid hit the plunger.
Anyhow like Masers maybe it could be revived. Time-nuts tend to do the
impossible.
Regards
Paul
WB8TSL

On Tue, Apr 13, 2021 at 9:45 AM Tom Van Baak <tvb at leapsecond.com> wrote:

> Jerry, thanks for posting that National Co Atomichron video link. And,
> Tim, thanks for posting the Smithsonian link.
>
> ---
>
> The first *laboratory* cesium standard was made by Louis Essen. Much has
> been written about this. My own pilgrimage:
>
>    http://leapsecond.com/museum/essen/
>
> The first *commercial* cesium standard was the Atomichron by the
> National Company. A short article here:
>
>
> https://www.rfcafe.com/references/radio-news/atomichron-worlds-most-accurate-clock-january-1957-radio-television-news.htm
>
> About 50 of these early cesium clocks were made. Several are known to
> still exist: one owned by the Smithsonian as Tim noted, one at the NAWCC
> museum, and at least two in private hands. Some photos of the one I
> found on eBay are here:
>
>    http://leapsecond.com/museum/nc2001/
>
> To get a feel for the size of this beast, here is a comparison of the
> Atomichron beam tube with a 5060 / 5061 / 5071 beam tube:
>
>    http://leapsecond.com/museum/nc2001/IMG_6441-600x800.jpg
>
> This photo is also attached (an excuse to test normal vs. digest mode
> photo handling). It's also featured here:
>
>    https://insidegnss.com/time-is-relative-position-absolute/
>
> ---
>
> If you are old enough to remember the vacuum tube and "atoms for peace"
> era you will appreciate the brilliant name choice for "Atomichron". A
> detailed Atomichron article by Paul Forman:
>
> https://ieee-uffc.org/about-us/history/uffc-s-history/atomichron/
>
> One interesting anecdote in the ieee article is Jerrold Zacharias and
> his "Fallotron", the original concept for what we now know as a Cesium
> fountain. And to wrap up this history of atomic clocks posting, here's a
> classic, including cesium and H-maser photos, by Norman Ramsey:
>
>    https://nvlpubs.nist.gov/nistpubs/jres/088/jresv88n5p301_A1b.pdf
>
> /tvb
>
>
> On 4/12/2021 11:45 AM, Tim Shoppa wrote:
> > For those interested in the National Company’s cesium clocks, you can
> > google “Atomichron” (their brand name) or check out this Smithsonian
> > archive: https://sova.si.edu/record/NMAH.AC.0547
> > <https://sova.si.edu/record/NMAH.AC.0547>
> >
> > Tim N3QE
> >
> > On Monday, April 12, 2021, Jerry Steinback via time-nuts <
> > time-nuts at lists.febo.com> wrote:
> >
> >> While munging around on Youtube, this short filmstrip popped up; it
> >> appears to be one of those short fillers for movie theater audiences.
> The
> >> first four minutes might be interesting to members of the group.
> >>      https://www.youtube.com/watch?v=NoDElB6HMCg
> >>
> >> Compared to any Cesium standard in the past couple(?) of decades it
> >> reminds me of the old Stan Freberg commercial for Contadina tomato
> paste:
> >> ''Who put eight great tomatoes in that little bitty can?''
> >> Jerry
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