[time-nuts] homebrew H maser

[Attila Kinali]

On Sun, 29 Aug 2010 10:03:02 -0700 (PDT)
"J. Forster" <jfor at quik.com> wrote:

> 
> [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.

Yes, but that's only half of the story. How do you make it vacuum tight?
And how do you design the end in the cavity so that you do not create
unwanted resonant modi?

 
				Attila Kinali
-- 
If you want to walk fast, walk alone.
If you want to walk far, walk together.
		-- African proverb