3. An oscillator is the basic element of all AC signal sources and generates sinusoidal signals of known frequency and amplitude.It is one of the basic and useful instruments used in electrical and electronic measurement. Oscillators are used in many electronics circuits and systems providing the central clock signal that controls the sequential operation of the entire system. a. Describe the operation of an OPAMP-based oscillator using the concept of a basic oscillator feedback circuit. Your description must include all pertinent equations relating the overall closed loop gain and the open-loop and feedback gain b. Figure 1 shows the complete schematic diagram of a variable frequency COLPITTS Oscillator. Use the MULTISIM platform to simulate the operation of this oscillator as you vary the values of the inductor, L,from 1µH to 62mH. What is the gain of the oscillator? i. Tabulate the output frequencies versus the various inductor values. ii. Show the output wave forms as displayed on the oscilloscope for ten selected frequencies. iii. Show the output wave forms as displayed on the spectrum analyzer of the output amplitude versus frequency.

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