Well, this is supposed to be a list about amateur precision timekeeping, so at the risk of looking like a total idiot, I'll take the bait and throw out a few questions.
First - I've only been on this list for about 6 months, and am only just beginning to get my head around some of the concepts regarding clocks, measurements and the transfer of time. I think its especially "timely" to be learning about this given the events at CERN - and I'm learning a lot from that too. That said, I've wondered how one as an individual/amateur might go about building an atomic clock. I've got another interest in machining and have a barn full of heavy cnc iron out back (old stuff, but good stuff - none less than 7000 ponds) that I'm slowly putting into service. So at its most basic, I'm wondering what type of clock would make the most sense to consider - cesium fountain, or hydrogen maser? I haven't done enough research in either to know which modes they oscillate the cavity in, but presumably, the cavity for the cesium is going to be a lot smaller just based on the oscillation frequency alone, so there is some cost benefit there. What about material availability? I don't know what form of cesium or hydrogen are needed, but I'm assuming that hydrogen is more available with less hassle? It seems like there are a few simple things that could be done to cheaply gain on the stability curve. I live in an area with a high water table (right next the the chesapeake bay). Why not drill a shallow well - 20ft?? to submerge the cavity and gain the thermal stability of the well? I'm from the subsea world, so putting something 20 feet down is nothing (most of my stuff goes to 6000m). Last - I've got a good friend that works at Jefferson Lab, involved in niobium deposition to get their cavity Q's up. What's the feasibility of an amateur doing something like that to improve cavity Q. Again - I apologize for my complete lack of knowledge on the subject, but these are just some of the ideas I've had bouncing around my head for how this might be done to make a pretty good clock on a pretty tight budget. Last - I hope you got to visit the USNO library - its definitely on of the coolest places to see for a scientist/engineer in DC. Brent On Tue, Sep 27, 2011 at 3:01 PM, Robert Darlington <[email protected]> wrote: > So I find that somewhat surprising (Aluminum as a material for UHV systems) > because they outgas water -for months. Anodized aluminum is especially > bad! Did they make any suggestions on cleaning the oxide off before pumping > down and baking? > > -Bob (machinist and vacuum nut) > > > > On Tue, Sep 27, 2011 at 12:56 PM, Poul-Henning Kamp > <[email protected]>wrote: > >> >> I just finished my Colloquium on leap-seconds at the USNO, and afterwards >> had lunch with Demitriou Matsakis and one of his Fountain building >> physicists. >> >> Remembering a previous discussion on the topic here, I asked if building >> a fountain would be a feasible amateur project. >> >> The answer is "yes, if you have enough money". >> >> The shared wisdom was that you want to build your vacuum vessel out >> of aluminium, which in addition to being a-magnetic also makes it >> possible to bolt the windows in, rather than mounting them by >> welding and that rubidium is a better target atom than cesium. >> >> Gentlemen, start your lathes... >> >> -- >> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 >> [email protected] | 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 -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
