That's why you want to look for the phase of the tank impedance. The phase goes through zero at resonance. It is far more precise. The steepness of the phase v. frequency plot is steep w/ a high Q circuit... flatter w/ a low Q tank. Either way, it does go through zero at resonance.
The phase v. freq looks kinda like this: Phase: /\ -------------/ \ /--------------- Freq \/ ^ resonance The dither sweep, amplituse measurement, lock-in will tune the oscillator to maximize the amplituse. Either on should pretty much steer you to resonance. -John ================== > >> I have a large LC tank, with a very lossy inductor. ... > >> So the question is, when actively driving a tank circuit, how do you >> know >> you are driving it with the same frequency ad the same phase it >> naturally >> oscillates at. > > If it's lossy, the peak will be broad so tuning the driving frequency > won't > be critical. > > How about just measuring the amplitude and tune for a max? I'm thinking > of > something like a diode and R/C filter feeding an ADC. > > > -- > These are my opinions. I hate spam. > > > > _______________________________________________ > 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.