EE 212 Lab
Prelab 12: Wien Bridge and Phase Shift Oscillators

1. Find the transfer function V_out(jw)/V_in(jw) for the circuit shown in figure 1 of the lab (where complex frequency variable s = jw can be substituted for ease of analysis.) Calculate values for R and C such that the phase shift between the output and input is zero for an input frequency of 10kHz. What is the amplitude ratio (gain) of the output to the input at this frequency.
2. The RC network in figure 3 of the lab can produce a phase shift of 180° at a desired frequency. Calculate this frequency for the network values given. (Recall a 180° phase shift corresponds to the transfer function V_out(jw)/V_in(jw) being a real negative number.) What is the gain of the circuit?