The ratio of the resonant frequency of the evacuated cavity to that of the air filled cavity increases by the square root of the relative permittivity of the ambient air or around 300ppm or so. Bruce
On Wednesday, 19 August 2015 5:06 PM, "cdel...@juno.com" <cdel...@juno..com> wrote: Hi everyone! I'm trying to figure out what change if any to a cavities resonant frequency would be when measured with ambient air pressure and then with a vacuum inside. There will not be any pressure on the cavity when under vacuum as the outside of the cavity will also be at vacuum. The cavity frequency under vacuum will be 1420Mhz + (Maser frequency). Thanks, Corby _______________________________________________ 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.