Hmm in interesting prospect. However its unclear to me as to the benefit of trying this. I do know what gets lost. Its not just a dimming of the light 1-2% as stated its also the modulation on the light beam. I think 286 Hz thats critical to locking the system. So the ccd is very capable of recovering that signal, but a lot of stuff to match the photo cell. Regards Paul. WB8TSL
On Wed, Feb 22, 2012 at 1:19 PM, Attila Kinali <[email protected]> wrote: > On Wed, 22 Feb 2012 09:14:34 -0700 > Tom Knox <[email protected]> wrote: > > > Rather then a simple lock LED I think what would be interesting if > possible > > to place a CCD next to a Rubidium or Cesium cell to view the luminance > at > > the hyperfine transiton. I am sure someone has done this but I have not > > seen it. > > I dont think this is easily possible. You have the CCD operating in a > strong > electromagnetic field which will disturb it quite a bit. Though i think > one could try to use one of the modern CCD like the OVM7690 (a tiny little > thing of just 2.5x2.5x2.9mm^3 and quite cheap too!) and mount it in some > empty corner that has little to no field. > > The other problem would be to see the luminance trough the strong > background. IIRC the "modulation" strength of the absortion is 1-2% > of the singal. So the luminance would be quite weak behind some strong > background light as well. > > But it would be nevertheless a cool project :-) > > Attila Kinali > > -- > Why does it take years to find the answers to > the questions one should have asked long ago? > > _______________________________________________ > 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.
