In this lab we will use positive feedback to produce two sinusoidal oscillators - the Wein bridge oscillator and the phase-shift oscillator, both described in Section 13.2 of Sedra and Smith.

PRE LAB -- Find the R and C need to make the Wein oscillate at 1 and 10 kHz. Find the R and C and gain need for the phase-shift oscillator to oscillate at 10 kHz.

A. Construct the non-inverting amplitude (part of circuit in Figure 5.42A in Horowitz and Hill). Leave off the RC positive feedback network for now.

B. Add the Wein bridge positive feedback for a frequency of 1 kHz.

C. Modify your oscillator to give an oscillation frequency of 10 kHz.

D. Construct and test a phase-shift oscillator of 10 kHz frequency (Sedra and Smith, Figure 13.8). Set the amplifier gain to compensate for losses in phase-shift network. Explain the circuit operation.