15.30 For the Colpitts oscillator circuit in Fig. P15.30, derive an equation governing circuit operation and hence find the frequency of oscillation and the condition the gain 8R, must satisfy for oscillations to start. Assume that R₁ includes the MOSFET's r. Note that this circuit is based on the configuration in Fig. 15.14(a). L C₁ Figure P15.30 C₁₂ 8 R₁.

Fig: 1