Figure 1. Shows the block diagram of a wideband frequency modulator using the indirect method. This modulator is used to transmit a voice signals containing frequencies in the range 300 Hz 3 KHz. The narrowband phase modulator is supplied with a carrier of frequency fj = 0.2 MHz by crystal controlled oscillator, carrier frequency at the transmitter output, fe = 200 MHz, minimum frequency deviation, Af = 120 KHz. Maximum modulation index, ß = 0.3 radians, (consider ß = 0.2 radian which certainly satisfies the requirements) (a) Calculate the frequency multiplication n2 (b) Calculate the carrier frequency for the second control oscillator f2. (c) Specify the values of carrier frequency and frequency deviation at the various points in the modulator. Frequency multiplier Integrator Narrow Frequency band multiplier Mixer phase Baseband signal signal ni- 50 FM modulator Crystal Crystal controlled controlled oscillator oscillator f: 0.2 MHz

Figure 1. Shows the block diagram of a wideband frequency modulator using the indirect method. This modulator is used to transmit a voice signals containing frequencies in the range 300 Hz 3 KHz. The narrowband phase modulator is supplied with a carrier of frequency fj = 0.2 MHz by crystal controlled oscillator, carrier frequency at the transmitter output, fe = 200 MHz, minimum frequency deviation, Af = 120 KHz. Maximum modulation index, ß = 0.3 radians, (consider ß = 0.2 radian which certainly satisfies the requirements) (a) Calculate the frequency multiplication n2 (b) Calculate the carrier frequency for the second control oscillator f2. (c) Specify the values of carrier frequency and frequency deviation at the various points in the modulator. Frequency multiplier Integrator Narrow Frequency band multiplier Mixer phase Baseband signal signal ni- 50 FM modulator Crystal Crystal controlled controlled oscillator oscillator f: 0.2 MHz

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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