Hi
> On Feb 22, 2018, at 8:22 AM, Attila Kinali <[email protected]> wrote: > > On Wed, 21 Feb 2018 18:10:17 +0000 > "Poul-Henning Kamp" <[email protected]> wrote: > >>> So the Rb85 "notch" filter might not get rid of all the unwanted light >>> and some of this might depopulate the excited state of the Rb87 >>> that are in the RF cavity. >> >> I have a hard time seeing how you can not get worse S/N that way. > > > Well, the question is how much? Keep in mind that an Rb lamp is > anything but a clean light source. The point is that it’s clean where it matters. It does not dump a bunch of energy into the transitions that you want to avoid. Bob > >> If you want to do it with a LED, I think it needs to be a stabilized >> LED-Laser. > > The problem with a Laser is that you need to lock it to the > right line. This requires either some significant change to the > electronics of the Rb standard, or an additional vapor cell and > some optics to lock it to that cell. Neither is trivial (apparently, > according to the papers I've read, not difficult, but I don't trust > that until I have tried myself). > > Attila Kinali > > -- > It is upon moral qualities that a society is ultimately founded. All > the prosperity and technological sophistication in the world is of no > use without that foundation. > -- Miss Matheson, The Diamond Age, Neil Stephenson > _______________________________________________ > 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.
