Paul Frankly I do not think I will live long enough to see a time nut build a fountain Rb. Over the four years I have watched many smoke and mirror projects with nothing coming out of is. In German we have a saying: paper is patient. We should walk before we run. Many members did buy a FE 5680, how many do you think are in operation, if, there would be discussions about its temperature performance. take a close look on page 7 figure 5 of the brochure, I also see it. Personally I use a Shera loop. But that is an overkill and for some to complex since it requires direct analog C field control. My real focus is on controlling FRK-H, M100 and HP 5065. What is needed is a coordinated effort to start with temperature control, a simple GPSDO only taking care of aging using RS232 interface an analog loop for controlling something like a Morion. Stability and accuracy could be in the 1 E-12 range, low cost able to be assembled by 90% of list members, but then I proposed it once before looking for some one to develop the filter. No response, it is clear that very few are willing or able to actually build something. When Corby wrote about his experience with the dual mixer / counter, large response and we will have a complete documentation set, but when I asked for a few that would be willing to build one right away, I would make complete kits, I got one response. Sad, but that is the reality. How many FE 5680A door stops do you think are out there? How many PICTICII's do you think are in use? Bert Kehren Miami. In a message dated 12/4/2012 9:49:29 A.M. Eastern Standard Time, [email protected] writes:
Basements the key. So for me bigger is better. Heck if its a rack thats ok. It gets interesting in what types of components you can use if you are willing to go larger. Great point on the laser and optics. Funny thing is for small change you can actually get used optics bench components at least at the last MIT flea I ran across the items. They were snapped up by the way. >From what I have seen of time-nuttery and Hydrogen masers I am actually not all that sure its beyond this group. Regards Paul On Tue, Dec 4, 2012 at 9:34 AM, Bob Camp <[email protected]> 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: [email protected] [mailto:[email protected]] 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=92hgj...@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 > [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. _______________________________________________ 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.
