[time-nuts] PTTI 2012, part 2

Bob Camp lists at rtty.us
Wed Dec 5 00:15:41 UTC 2012


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 <docdailey at 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" <lists at 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-bounces at febo.com [mailto:time-nuts-bounces at 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=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.
>> 
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at 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 at 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 at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.




More information about the time-nuts mailing list