Hi Ok, how many full performance Hydrogen Masers can you build (size is not an issue) and deliver for < $10,000 (2X Bert’s number) ?
Bob > On Nov 3, 2016, at 8:55 PM, Tim Shoppa <[email protected]> wrote: > > It would obviously be larger than a homebrew Cs, but why not a homebrew > Hydrogen Maser Frequency standard? > > The commercial Cs units always seemed objects of pure miniaturized hi-tech > materials science magic, while the Hydrogen Masers I've seen seem much > larger-scale\ and more a matter of vacuum plumbing. Obviously the materials > cost for the copper microwave cavity will be very large, and I'm sure > Teflon-coating a quartz chamber is an art, but the pumps and magnets are > very familiar from my years in grad school working with plasma kettles and > mass spectrometers. > > Tim N3QE > > > > > > On Thu, Nov 3, 2016 at 4:07 PM, Bert Kehren via time-nuts < > [email protected]> wrote: > >> >> Over the past there has been talk about building from scratch high >> performance references. I think consensus was that it is out of reach. In >> the mean >> time Corby is reworking an active maser which takes a lot of know how. But >> let us look at his work on the super HP5065. It is able to outperform a >> passive maser in the below 100 second range! Long term a proper GPSDO >> should >> be possible to step in. We are working on it including pressure and >> temperature control. To make full use of it you also need to have the >> capability >> to monitor, record and analyze on a continuous basis preferably with out >> tying up expensive equipment. We have the pieces in place and looking >> forward >> of combining all the pieces and compare with Corby’s active Maser. We are >> back to the GPSDO after being distracted by Tbolt performance. A third >> party >> is working combining the GPSDO data stream with the data from the unit >> that >> generates frequency, pressure and temperature data along with time to a >> USB stick, while also be able to monitor with a PC. >> I know it is considered by some heresy but our lack of a Maser and in >> Juerg >> ’s case no access to one, we try to overcome it with a GPSDO tailored for >> Rb and Cs and control our Cs’s C field . >> There was a time that I did have a HP5065A but got rid of it when I got >> some Cs’s. My best counter was A HP5345 and even with a Tracor 527 1 >> second >> performance was not an issue. That changed when Corby introduced me to >> time >> nuts and frankly it was the first time I learned about ADEV. But the >> HP5065A was gone. Now I have a cell that Corby has plotted and time >> permitting >> may become a project. >> Let me get to the real issue. There are not enough HP5065A’s out there and >> not affordable for all time nuts. Most are being kept and are not for >> sale. But if a combined effort by many time nuts it MAY be possible to >> recreate >> the guts of the HP5065A. The key word is MAY. 200 time nuts be willing to >> invest $ 5000 each may get us there. The market does not justify such an >> effort but time nuts keep bringing up discussions. All the other ideas >> kicked >> around in the past will cost more. There are some among us that know what >> it cost and who can make the key elements like lamps, cells, filters etc. >> Just a thought outside the box and hopefully may turn in to a limited >> constructive dialog. We will continue on our path, which include >> FRK/M100, HP5065 >> and Cs. >> We would not be capable to contribute technically on the physics package >> but I would be willing to contribute financially and with monitoring >> equipment even if I would not be around when finished. >> Bert Kehren >> _______________________________________________ >> 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.
