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APPARATUS : 1. TIMS-301 Modelling System 2. C.R.O (20MHz) 3. Spectrum Analyzer 4. Connecting chords & probes. AM Signal, S(t) = E(1 + m·cos(μt)) · cos(ωt) Where, E is the amplitude of the AM signal μ is the frequency of the message signal (in rad/s) ω is the frequency of the carrier signal (in rad/s) m is the modulation index (varies from 0 to 1) = {A(1 + m·cos(μt))} × {B·cos(ωt)} = {low frequency term a(t)} × {high frequency term c(t)} The low frequency term can be considered as: a(t) = DC + m(t) Using an adder, we try to keep the modulation index or modulation depth exactly 100%. Figure: AM, with m = 1 For example, if we set DC voltage to A volts and the amplitude of the AC part as A·m, then the ratio is 1 at the adder output, indicating 100% amplitude modulation. Circuit Diagram Figure: AM Circuit PROCEDURE : 1. Generate a message signal from the AUDIO OSCILLATOR module. The oscillator ...