Hi The obvious question would be: What does it cost to set up a line to make a proper set of spherical Rb cells? Doing this as a glassblowing project is a dead end. You need it properly tooled ….
Bob > On Jan 11, 2017, at 7:05 PM, Bruce Griffiths <bruce.griffi...@xtra.co.nz> > wrote: > > Angus > Read the paper I posted on the current state of the art. > ADEV ~ 2E-13/SQRT(Tau) is feasible with large cells and using a laser instead > of rubidium lamp.In principle, one can use the same cell to lock the laser to > the rubidium absorption line and lock the microwave signal.Suitable laser > diodes are readily available. > Increasing the contrast of the signal used for locking reduces the noise > significantly.One approach is to use an integrating sphere cell and use an > optical fibre to bring the laser signal into the cell.Since random scattering > in an integrating sphere depolarises the light and virtually eliminates any > effect of spatial coherence a multimode fibre should suffice.Laser speckle > can be reduced significantly by using a colloidal suspension of titanium > dioxide if the colloidal suspension fills another integrating sphere or > equivalent.I've tried the latter using plastic optical fibres to transport > the laser light into and out of the colloid. Its extremely effective in > eliminating speckle in an optical interferometer. > Bruce > > On Thursday, 12 January 2017 12:19 PM, Angus <not.ag...@btinternet.com> > wrote: > > > On Tue, 10 Jan 2017 21:43:07 -0500, you wrote: > >> >> This does get back to state of the art Rb and what that means. In my >> suggested case thats measured in terms of ADEV for Tau = 1 to 1,000,000 >> seconds. If you wanted an Rb with (only) state of the art phase noise at 1 >> MHz offset … thats a different thing. State of the art for >> power consumption and size is also not what Im suggesting in this case. Why >> the choice of spec? … this is TimeNuts. > > Hi, > > Some discussions on the performance that might be practically achieved > with different designs may be a useful start - as long as it's done in > the context of a practical unit that could actually get built, rather > than just a theoretical wish list. > > It would also be good to have some idea of the cost of any special > parts like cells too. Without that info, it's hard to know how > practical particular designs would be. > > Looking at export/technology controls might be useful early on too, > since we're going for high performance. > > I've often wondered how a 21st century version of a 5065 would > perform, so it's great to see that I'm not completely alone in my > insanity! > > Angus. > > > _______________________________________________ > 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. > > > > _______________________________________________ > 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. _______________________________________________ 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.
