[snip] >> complicating aspect is the self-tuning stuff for which several >> strategies may be chosen. > > I'd start here at getting a cavity that is resonant at the frequency > at all. Getting sub-milimeter precision in tooling is quite easy > (given you have the tools and knowledge, or can pay someone to do it for > you), > but if the cavity has to be resonant within a couple of Hz of the > 1.4xxxGHz, then you have to get a precission in the range of 10^-9 > which basically impossible mechanically. So the cavity would need to have > a mechanical tuning system too, but one that doesn't lower the cavity's > Q or add any additional resonant modes.
A tuning plunger driven with a Burleigh Inchworm, either through a bellows or with a vacuum Inchworm. >> You need to balance the rate of the atoms, as both too few and too many >> kills the oscillation. There are commercial adjustable leaks and Mass Flow Controllers by MKS for example. > Or get to the basic requirement of getting a pure H2 source to feed > the beam source. The beam source itself, including the dissociator, > would be a formidable project to do at home by itself. Kimball Physics sells parts for doing this. >> The size of the glass-bulb is not a fixed thing, during research and >> development different sizes glass-bulbs is used to establish the >> wall-shift aspects in order to adjust for it, which is needed in order >> to make absolute measurements on the "free" atom resonance or compensate >> into that regard. > > Interestingly, i think that the bulb would be the easiest part > these days. At least around here, there are a few glas blowers > for the chemical/pharmaceutical industry that also do single pieces. > Getting it coated would only involve finding a company that does > teflon coating (there do seem enough of them). From what i gather > it's shape doesnt have to be exactly spherical down to the > sub-milimeter range. > >> As for reference, there is about one set of books and papers from a >> handful of journals and a bunch of patents which needs to the read in >> order to build up the knowledge-base for attempting something like it. > > Which papers/books would you recommend reading? > > And no, i don't think i'd attempt to build a H maser. > I'm quite confident i could do the electronics part, but i know that > i don't know anything when it comes to mechanics. Much less about > handling high vacuum and atomic gas beams. The pumping is pretty straight forward. You would likely need a source of LN2, at least for a while. The vacuum needs to be clean, which means traps. Sorbtion & ion or Ti sub pumps would be a better idea. >> It's a complicated field and several traps to fall into on the way. It >> is a fairly sizeable project to attempt. > > Yes, but it's fun to read about it :-) > > Attila Kinali Best, -John =============== _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
