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Design an RC phase shift oscillator to have an output frequency of $600 \mathrm{~Hz}$. Use $\pm$ $15 \mathrm{~V}$ supply.
select a value of $c$; Let $C=0.1 \mathrm{MF}$ calculate value of $R$ from $f_0$ $f_0=\frac{1}{2 \pi \sqrt{6} R c}\$ \begin{aligned}\ &\therefore R=\frac{1}{2 \pi \sqrt{6} f_0 c} \\ &\therefore R=1082 \Omega \\ &\text { Let } R=1 \mathrm{k} \Omega\ \end{aligned}\ To prevent loading of 0,1 -amp by $R C$ network choose $R_1$ much larger than R \text { Let } \begin{aligned}\ R_1 & \geq 10 R \\ R_1 &=10 \times 1 \mathrm{k} \Omega \\ R_1 &=10 \mathrm{k} \Omega\ \end{aligned}\ The gain of op-amp in the phase shift oscillator is $2 g$ $\therefore \frac{R_F}{R_1}=2 \mathrm{~g}\$ \begin{aligned}\ \therefore \quad R F &=29 \times R_1 \\ \therefore R F &=29 \times 10 \mathrm{k} \Omega \\ \therefore \quad R F &=290 \mathrm{k} \Omega\ \end{aligned}\