May I please ask why my phase shift oscillator as shown is not oscillating? My R1=R2=R3, and C1=C2=C3. I am trying to get around 1kHz of oscillation, so using the simple equation of fr=1/(2*piRC*sqrt(6)), I get all the values as shown in the pictures.
But why is it not oscillating? I tried at both Multisim and LTSpice, but it just doesn't simulate. I am using ideal opamp at both simulators (gain is very high, 200x let say). I put Rf(feedback resistor of opamp) to be 220k to have Rf>29*R, which will make the loop gain >1 (to fulfill the Berkhausen criteria), but it is still not oscillating. I thought the circuit fulfills both of the criterion for oscillating to happen?
I tried changing Rf to even higher value, and even play with the RC values. I also tried to use LM741 op amp and rise the supply voltage slowly, but I never get oscillation. May someone please give me enlightenment on what is wrong/lacking? Thank you very much.