The primary disadvantage of FM is its Ans Excessive use of spectrum space 21

The primary disadvantage of fm is its ans excessive

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20.The primary disadvantage of FM is its 21.Noise is primarily 22.The receiver circuit that rids FM of noise is the 23.The phenomenon of a strong FM signal dominating a weakersigna on a common frequency is referred to as the 24.The AM signals generated at a low level may only beamplified by what type of amplifier? 25.Frequency modulation transmitters are more efficientbecause their power is increased by what type of amplifier 26.Noise interferes mainly with modulating signals that are 27. Pre-emphasis circuits boost what modulating frequencies before modulation? Ans: high frequencies 28. A pre-emphasis circuit is a Ans: high pass filter 29. Pre-emphasis is compensated for at the receiver by Ans: low-pass filter 30. The cut-off frequency of pre-emphasis and de-emphasis circuits is Ans: 2.122 kHz Chapter 5: FM Circuits 1. Another name for a VVC is Ans: varactor diode 2. The depletion region in a junction diode forms what part of a capacitor Ans: dielectric 3. Increasing the reverse bias on a varactor diode will cause its capacitance Ans: decrease 4.The capacitance of a varactor diode is in what general range 5.In Fig. 5-3, the varactor diode is biased by whichcomponents? 6.In Fig. 5-3, if the reverse bias on D1is reduced, the resonantfrequency of C1 7.The frequency change of a crystal oscillator produced by avaractor diode is 8.A phase modulator varies the phase shift of the 9.The widest phase variation is obtained with a(n) 10.In Fig. 5-7, R4is the 11.The small frequency change produced by a phase modulatorcan be increased by using a(n) 12.A crystal oscillator whose frequency can be changed by aninput voltage is called a(n) ©2008 Created by Kai Raimi – BHC COMMUNICATION ELECTRONIC 2 ND EDITION - FRENZEL 4
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13.Which oscillators are preferred for carrier generatorsbecause of their good frequency stability? 14.Which of the following frequency demodulators requires aninput limiter? 15.Which discriminator averages pulses in a low-pass filter? 16.Which frequency demodulator is considered the bestoverall?
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