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Answer :

In AM the amplitude of carrier components remains constant, while in FM it does not remain constant.

Related questions

Description : In_____ transmission, thephaseof the carrier signal is modulated to follow the changingvoltage level (amplitude) of the modulating signal. A) AM B) PM C) FM D) none of the above

Last Answer : PM

Description : In_____ transmission, the frequency of the carrier signal is modulated to follow the changing voltage level (amplitude)of the modulating signal. The peak amplitude and phase of the carrier signal remainconstant,but as ... of thecarrier changes correspondingly. A) AM B) PM C) FM D) none of the above

Last Answer : FM

Description : Which determines the number of sideband components of FM? A. Modulation frequency B. Modulation index C. Carrier frequency D. All of these

Last Answer : B. Modulation index

Description : Indicate which one of the following is NOT an advantage of FM over AM? (1) Better noise immunity is provided (2) Lower bandwidth is required (3) The transmitted power is more useful (4) Less modulating power is required 

Last Answer : Indicate which one of the following is NOT an advantage of FM over AM? (1) Better noise immunity is provided (2) Lower bandwidth is required (3) The transmitted power is more useful (4) Less modulating power is required 

Description : In amplitude modulation AM, if modulation index is more than 100% then: (1) Power of the wave increases. (2) Efficiency of transmission increases. (3) The wave gets distorted. (4) Bandwidth increases

Last Answer : In amplitude modulation AM, if modulation index is more than 100% then: The wave gets distorted.

Description : In_____ transmission, thecarrier signal is modulated so that its amplitude varies with the changing amplitudes of the modulating signal. A) AM B) PM C) FM D) none of the above

Last Answer : AM

Description : Theoretical bandwidth requirement for FM system is: (1) Same as that of the modulating signal bandwidth (2) Twice of modulating signal Bandwidth (3) Thrice as of modulating signal Bandwidth (4) Infinite 

Last Answer : Theoretical bandwidth requirement for FM system is: Infinite

Description : In commercial FM broadcasting, the maximum frequency deviation is normally   (A) 5 KHz (B) 15 KHz (C) 75 KHz (D) 200 KHz

Last Answer : In commercial FM broadcasting, the maximum frequency deviation is normally 75 KHz

Description : The frequency range of FM radio is

Last Answer : The frequency range of FM radio is 88MHz to 108MHz

Description : An amplitude modulation performs the mathematical operation of (A) Division (B) multiplication (C) subtraction (D) addition

Last Answer : An amplitude modulation performs the mathematical operation of multiplication

Description : A 1 Mhz carrier is amplitude modulated by a pure 200-Hz audio test tone. Which of the following combinations of frequencies represent the total content of the AM signal? A. 1 MHz and 200 Hz B. 1 MHz and 1000.2 kHz C. 999.8 kHz, 1000 kHz, and 1000.2 kHz D. 999.8 kHz and 1000.2 kHz

Last Answer : C. 999.8 kHz, 1000 kHz, and 1000.2 kHz

Description : If the percentage modulation of an AM amplifier is 88% and the modulating signal is 1 volt, the carrier has an amplitude of _______________. A. 1.14 volts B. 0.88 volt C. 1.88 volts D. 0.12 volt

Last Answer : A. 1.14 volts

Description : Three audio waves with 100,200 and 300 volts amplitude respectively, simultaneously modulate a 450 volts carrier. What is the total percent of modulation of the AM wave? A. 69 % B. 115.5 % C. 50% D. 83%

Last Answer : D. 83%

Description : A 400 W carrier is amplitude modulated to a depth of 75%.Calculate the total power in AM wave. (i) Explain the types of noise in a communication system. (ii) Compare simplex and duplex mode of communication.

Last Answer : (i) Noise: Noise is any spurious or undesired disturbances that mask the received signal in a communication system. a) Atmospheric Noise: Atmospheric Noise is also known as static noise which is the ... remote control ExamplesWalkytalky,telephone,mobile,Radar, FAX,Pager 4

Description : In the case of a 70–MHz IF carrier for a transponder bandwidth of 36 MHz, energy must lie between MHz: (1) 34 and 106 (2) 52 and 88 (3) 106 and 142 (4) 34 and 142

Last Answer : In the case of a 70–MHz IF carrier for a transponder bandwidth of 36 MHz, energy must lie between MHz: 52 and 88

Description : One of the FM signal generator control which varies the phase of the modulating voltage applied to the oscillator of the sweep generator A. Band control B. Phase control C. Marker amplitude control D. Sweep output control

Last Answer : B. Phase control

Description : In an FM receiver, which circuit removes amplitude variations? A. Exciter B. Mixer C. Discriminator D. Limiter

Last Answer : D. Limiter

Description : In FM, frequency of modulated wave varies with A. amplitude B. time C. wavelength D. energy

Last Answer : time

Description : Explain the working of amplitude limiter in FM receiver with circuit diagram.

Last Answer : Amplitude limiter: The function of amplitude limiter is to remove all amplitude variation of FM carrier voltage that may occur due to atmospheric disturbances. Use of amplitude limiter makes the system less noisy  Circuit Diagram:

Description : What is the channel number of an FM station with a carrier frequency of 99.5 MHz? A. 256 B. 258 C. 257 D. 259

Last Answer : B. 258

Description : What is meant by the term modulation index? A. The processor index. B. The ratio between the deviation of a frequency modulated signal and the modulating frequency. C. The FM signal-to-noise ratio. D. The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency.

Last Answer : B. The ratio between the deviation of a frequency modulated signal and the modulating frequency.

Description : The carrier swing necessary to provide 80% modulation in the FM broadcasting band is __________. A. 150 kHz B. 120 kHz C. 60 kHz D. 75 kHz

Last Answer : B. 120 kHz

Description : A 1000W carrier is amplitude modulated to a depth of 85%. Calculate the total power of the modulated wave? A. 1361.25 W B. 680.62 W C. 1425 W D. 712.5 W

Last Answer : A. 1361.25 W

Description : What is the first symbol of a radio signal transmission having an amplitude modulated signal carrier, double side band? A. C B. B C. H D. A

Last Answer : D. A

Description : Refers to the first symbol in an emission designation with an amplitude modulated main carrier represented by letter H. A. Single sideband suppressed carrier B. Double sideband full carrier C. Independent sideband D. Double sideband

Last Answer : B. Double sideband full carrier

Description : This is referred to a product of simultaneous frequency and amplitude modulation or a carrier frequency variation which produces unwanted distortion. A. Absorption modulation B. Simultaneous modulation C. Dynamic instability D. Series modulation

Last Answer : C. Dynamic instability

Description : In amplitude modulation technique the unmodulated carrier is referred to as having ______. A. 100% modulation B. 0% modulation C. 50% modulated D. Over modulated

Last Answer : B. 0% modulation

Description : Modulation means A. Varying of information B. Utilization of a single transmission channel to carry multiple signals C. Varying of some parameters of a carrier such as its amplitude to transmit information D. Transmit pulses in DC form on a copper wire

Last Answer : C. Varying of some parameters of a carrier such as its amplitude to transmit information

Description : A carrier signal has ______. A. Constant peak amplitude B. The information C. Frequency range 20-20000 Hz D. A varying amplitude

Last Answer : A. Constant peak amplitude

Description : Variation in amplitude or frequency of carrier wave is called A. amplitude modulation B. frequency modulation C. modulation D. bandwidth

Last Answer : modulation

Description : In_______, the peakamplitude of one signal level is 0; the other is thesame as the amplitude of the carrier frequency. A) PSK B) OOK C) FSK D) none of the above

Last Answer : OOK

Description : In________, the amplitude of the carrier signal is varied to create signal elements. Both frequency and phase remainconstant. A) ASK B) PSK C) FSK D) QAM

Last Answer : ASK

Description : A 4 GHz carrier is amplitude modulated by a low-pass signal of maximum cut off frequency 1 MHz. lf this signal is to be ideally sampled, the minimum sampling frequency should be nearly

Last Answer : A 4 GHz carrier is amplitude modulated by a low-pass signal of maximum cut off frequency 1 MHz. lf this signal is to be ideally sampled, the minimum sampling frequency should be nearly 4 Ghz

Description : Most AM broadcasts employ ___ polarization while most FM broadcasts employ ___ polarization of the radio wave. A. vertical, vertical B. vertical, horizontal C. horizontal, vertical D. horizontal, horizontal

Last Answer : B. vertical, horizontal

Description : To predict failure in design components which failure criteria is not assumed, when mean stress and stress amplitude are nonzero? a. Goodman criterion b. Soderberg criteria c. Gerber criteria d. None of the above

Last Answer : d. None of the above

Last Answer : Noise limiter is provided on AM receivers to reduce interfering noise due to ignition system, reduce noise due to electrical storms, reduce interference due to electrical machinery.

Description : What is the amplitude and voltage induced into the rotor when the CX is turned 90º while the CT remains on electrical zero?

Last Answer : The voltage is maximum and in phase with the ac excitation voltage to the CX.

Description : What effect does inductance have (a) on steady direct current and (b) on direct current while it is changing in amplitude?

Last Answer : a) No effect. (b) Inductance opposes any change in the amplitude of current.

Description : Are your radio stations that FM is religious and country music and AM urban and rock and roll?

Last Answer : Just the opposite here. Music (top 40, oldies, etc.,) are all on FM because the sound is so much cleaner and immune to static. AM gets sports, preachers, and talk radio, because sound quality isn’t that important.

Description : Can you suggest a good FM/AM radio?

Last Answer : Car radios are pretty good at picking up weak signals. In my house, I have a separate tuner and amplifier, and I can’t pick up signals that my car radio picks up with ease.

Description : What's a quick, easy and inexpensive way to boost the am/fm signal to my home radio?

Last Answer : These are rated pretty high by customer reviews, it only does FM. if you don’t like it it can be returned for a refund. http://www.amazon.com/Terk-Outdoor-Dual-Drive-Amplified-Antenna/dp/B00009UHYQ/ref=sr_1_1?ie=UTF8&qid=1422930976&sr=8-1&keywords=terk+fm+50

Description : Where can I buy a table top radio, with remote, that receives HD, AM and FM bands?

Last Answer : I was recently shopping for a new radio, too, and did some research, but nowhere could I find one with the kind of high-end features you want for less than hundreds. This Bose is a wonderful radio, but unfortunately, costs 3X. This if one of the lists I was looking at.

Description : Could someone give a simple high level explanation of what is meant by AM and FM?

Last Answer : Well, have a look at this picture

Description : Generally, what do you get from AM radio that you don't get on FM radio, and vice versa?

Last Answer : I love the smooth, clear sounds of FM and loathe the shrill commercials of AM radio.

Description : I was wondering if there are any bluetooth mp3 players that have am/fm radio?

Last Answer : Here’s one, but without the AM frequency . . . http://www.google.com/products/catalog?hl=en&q=portable+bluetooth+mp3+player&show=dd&cid=6021463648594635818&sa=title&os=tech-specs

Description : Do you listen to the regular AM/FM radio still?

Last Answer : I listen to the radio almost never. I listen to mp3 audio books.

Last Answer : AM / FM - Amplitude / Frequency Modulation.

Last Answer : Amplitude / Frequency Modulation.

Description : Can I set the Sony ICFCD7000 AM/FM/CD clock radio to play my favorite CD track each time the alarm rings in the morning?

Last Answer : It can play the first song on your CD to wake you up in the morning.

Description : Is there a portable CD player with an AM/FM radio?

Last Answer : There are several models that have AM/FM radios that are built into them.