[time-nuts] Maser manual
szeker.k at gmail.com
Thu Sep 2 10:02:25 UTC 2010
I have the coodinates yet too(but not the hight over see):
2010/9/2 K. Szeker <szeker.k at gmail.com>:
> Hi all,
> The "Neuchatel MASER" was build by Oscilloquartz in Neuchatel/Switzerland...
> Maybe somebody has the full coordinates of that :-)
> Oscilloquartz SA, http://www.oscilloquartz.com/
> Brévards 16
> 2002 Neuchâtel
> phone : +4132 722 5555
> fax : +4132 722 5556
> 2010/9/1 Magnus Danielson <magnus at rubidium.dyndns.org>:
>> On 09/01/2010 09:39 PM, Poul-Henning Kamp wrote:
>>> In message<24C547B54EA34A69BACC4F823BB4036F at pc52>, "Tom Van Baak" writes:
>>>> I found the original copies of both EFOS manuals, along with
>>>> a few photos. See:
>>> Page 4/3 in the service manual states:
>>> For the Hydrogen Maser, this unperturbed frequency
>>> f(H) = 1 420 405 751.768 +/- 0.002 Hz
>>> In practice, this frequency is perturbed by
>>> interaction of the hydrogen atoms with the walls
>>> of the interaction volume container, doppler
>>> effects, interactions between the atoms themsel-
>>> ves, etc. The resulting frequency for the EFOS
>>> Maser is taken to be
>>> F(o) = 1 420 405 751.689 Hz
>>> I have no idea where the EFOS was produced, but somebody should try
>>> to calculate the relativistic correction for their height above the
>>> geoid, and see how much of the systematic 0.079Hz frequency difference
>>> that explains...
>> Neuchatel, which still leaves a bit of unspecified height.
>> However, this effect would be cancelled as their cesium clocks would be on
>> the same height above the geoid (give or take a few meters).
>> So, their indication is correct. The C-field also pulls the atoms of course,
>> which they failed to point out in the cited text.
>>> If I were to build a maser myself, I would probably not attempt
>>> to copy the EFOS, as the large mechanical dimensions add significant
>>> cost in materials and machining.
>>> I would be much more tempted by a sapphire loaded cavity design like
>>> this one:
>>> As that brings the mechanics inside the work envelope of main-stream
>>> CNC machines with the required tolerances.
>> Yes, but what is the issues relating to sapphire loading? What's the cost of
>> the sapphire block and having it machined?
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