But it is as Richard said and after he sent it I remembered reading about it in the "Quantum beat". The trick is to get that accurate frequencies sideband to land on the RB or CS frequency. Just 1 sideband. So using a large step synthesizer and then another to get the finer detail is a reasonable way to go. Regards
On Tue, Apr 11, 2017 at 10:13 PM, Bob kb8tq <kb...@n1k.org> wrote: > Hi > > If you make the cells in the basement (or even in most factories) the > ability to have a wide range > synthesizer will come in handy. The whole “6.834xxx GHz” thing is > dependent on a number of variables. > It is not at all uncommon to produce cells that come out 10’s or 100’s of > KHz off of the “right number”. > Wide range synthesizer = higher yield. > > Bob > > > On Apr 11, 2017, at 10:00 PM, Richard (Rick) Karlquist < > rich...@karlquist.com> wrote: > > > > You always want two frequency sources. One generates a carrier > > frequency offset many MHz from 6.834 GHz and the other frequency > > source modulates the carrier with a sideband that is at the > > exact ~6.834 GHz frequency that finds the atomic line. The > > sideband is in turn modulated with audio to find the exact > > center of the line. This is now the easiest section to > > design. > > > > This architecture automatically gives you gobs of resolution. > > Of course you always have the C field for infinite resolution. > > The other thing it does is prevent RF leaks from exciting the > > atoms, since the strong LO is safely offset from 6.834. > > > > Rick N6RK > > > > On 4/11/2017 2:59 PM, paul swed wrote: > >> When I read about the frequency generation in the Rb or CS there are > >> normally many numbers associated with the actual frequency. Down to at > >> least the 1 Hz level. Many of these PLLs are intended for multi-KHz > steps. > >> I speculate you might need 2 PLLs one thats very fine in I hz increments > >> that gets added to something like these PLLs that step in 200 KHz > >> increments. > >> Regards > >> Paul > >> WB8TSL > >> > > _______________________________________________ > > 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.
