constant
Description : If frequency of modulated wave is less than frequency of carrier wave, then input signal is A. negative B. positive C. zero D. infinite
Last Answer : negative
Description : In FM, frequency of modulated wave varies with A. amplitude B. time C. wavelength D. energy
Last Answer : time
Description : Amplitude of modulated wave is in phase with A. output B. system C. frequency D. signal
Last Answer : signal
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 : What type of transmission is radiated from an aircraft’s radio altimeter antenna? A. An amplitude modulated continuous wave B. A pulse position modulated UHF signal C. A differential phase shift keyed UHF signal D. A frequency modulated continuous wave
Last Answer : D. A frequency modulated continuous wave
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 : The audio signals of TV are – (1) Amplitude modulated (2) Frequency modulated (3) Unmodulated (4) Velocity modulated
Last Answer : (2) Frequency modulated Explanation: In analogue television, the sound portion of a broadcast is invariably modulated separately from the video. Most commonly, the audio and video are combined at ... visual antennas can be used. In almost all cases, standard wideband frequency modulation is used.
Description : The audio signals of TV are : (1) Amplitude modulated (2) Frequency modulated (3) Unmodulated (4) Velocity modulated
Last Answer : (2) Frequency modulated Explanation: In telecommunications and signal processing, frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with ... , the sound portion of a broadcast is invariably modulated separately from the video.
Description : The audio signals of TV are (1) Amplitude modulated (2) Frequency modulated (3) Unmodulated (4) Velocity modulated
Last Answer : Frequency modulated
Description : A modulation which does not follow the sine wave pattern, it produces undesirable harmonics such as spurious emission A. 0% modulated B. Over-modulated C. Unmodulated D. 100% modulated
Last Answer : B. Over-modulated
Description : Modulation in which the modulated wave is always present. A. Carrier modulation B. Front-end C. Continuous modulation D. Log-periodic modulation
Last Answer : C. Continuous modulation
Description : If the carrier of a 100 percent modulation modulated AM wave is suppressed, the percentage power saving will be (A) 50.55 (B) 15.55 (C) 10.66 (D) 66.66
Last Answer : If the carrier of a 100 percent modulation modulated AM wave is suppressed, the percentage power saving will be 66.66
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 : 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 : 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 ratio of the level of the modulated output of a transmitter under conditions of standard test modulation to the level of the demodulated output with no modulation applied both measured with the ... . Reference audio output B. None of these C. Audio frequency response D. Residual noise level
Last Answer : D. Residual noise level
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 : Draw amplitude modulated waveform in time domain and frequency domain with proper labeling.
Last Answer : AM in Time domain AM in frequency domain
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 : For an electromagnetic wave traveling in a vacuum, if the magnitude of the intensity of the E field is zero, the magnitude of the intensity of the B field is: w) zero x) a negative maximum y) a positive maximum z) the square root of 2 times the positive maximum
Last Answer : ANSWER: W -- ZERO
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 : How does the energy of a wave depend on its frequency if the amplitude stays constant?
Last Answer : Feel Free to Answer
Description : A constant potential difference is applied across the plates of a parallel-plate capacitor. Neglecting any edge effects, the electric field inside the capacitor is: w) constant x) varying as one over r squared y) decreasing as one moves from the positive to the negative plate z) zero
Last Answer : ANSWER: W -- CONSTANT
Description : In modulation technique, which of the following is referred to audible pitch? A. Width B. Frequency C. Harmonic D. Amplitude
Last Answer : B. Frequency
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 : Which of the following systems is not used in radio detection and ranging? A. Frequency shift B. Frequency modulation C. Pulse radar D. Amplitude modulation
Last Answer : D. Amplitude modulation
Description : Used for time division multiplexing. A. Frequency modulation B. Pulsed modulation C. SSB D. Amplitude modulation
Last Answer : B. Pulsed modulation
Description : Bits can be sent over guided and unguided media as analog signal by ___________ a. digital modulation b. amplitude modulation c. frequency modulation d. phase modulation
Last Answer : a. digital modulation
Description : A pulse modulation technique as the width of a constant amplitude pulse is varied proportional to the amplitude of the analog signal at the time the signal is sampled.
Last Answer : PWM, PLM, PDM
Description : The quality or tone of a musical sound produced by a stringed instrument depends on – (1) frequency of vibration (2) length of the strings in the instrument (3) Amplitude of vibration (4) wave form of the sound
Last Answer : (4) wave form of the sound Explanation: The timbre or quality of a sound depends on its wave form, which varies with the number of over-tones, or harmonics, that are present, their ... particular musical sound have a different sound from another, even when they have the same pitch and loudness.
Description : Quality of a musical note depends on – (1) Fundamental frequency (2) Amplitude of the wave (3) Harmonics present (4) Velocity of sound in the medium
Last Answer : (3) Harmonics present Explanation: Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly ... and the attack-decay envelope of the sound. Harmonic content is the most important of these.
Description : Of the following properties of a wave, the one that is independent of the other is its (1) amplitude (2) velocity (3) wavelength (4) frequency
Last Answer : (1) amplitude Explanation: The maximum extent of a vibration or oscillation, measured from the position of equilibrium.
Description : When a light wave is reflected from a mirror, there is a change in its – (1) frequency (2) amplitude (3) wavelength (4) velocity
Last Answer : (2) amplitude Explanation: When a light wave is reflected from an object, it changes not only its amplitude but also its phase according to the properties of the object at a particular point. The velocity and momentum are just reversed in another direction.
Last Answer : a) amplitude Explanation: The maximum extent of a vibration or oscillation, measured from the position of equilibrium.
Description : If viewed on an oscilloscope, the loudness of a sound wave would be associated with the wave's: w) frequency x) wavelength y) velocity z) amplitude
Last Answer : ANSWER: Z -- AMPLITUDE
Description : Which of the answers listed below best completes the statement: The rate at which any part of a wave travels from one place to another determines the wave's: w) propagation velocity x) period y) amplitude z) frequency
Last Answer : ANSWER: W -- PROPAGATION VELOCITY
Description : Quality of a musical note depends on (1) Fundamental frequency (2) Amplitude of the wave (3) Harmonics present (4) Velocity of sound in the medium
Last Answer : Harmonics present
Description : The quality or tone of a musical sound produced by a stringed instrument depends on (1) frequency of vibration (2) length of the strings in the instrument (3) Amplitude of vibration (4) wave form of the sound
Last Answer : wave form of the sound
Description : When a light wave is reflected from a mirror, there is a change in its (1) frequency (2) amplitude (3) wavelength (4) velocity
Last Answer : amplitude
Description : Inan HFC network, the upstream data are modulated using the _______ modulation technique. A) QAM B) QPSK C) PCM D) ASK
Last Answer : QPSK
Description : Inan HFC network, the downstream data are modulated using the _______ modulation technique. A) PSK B) QAM C) PCM D) ASK
Last Answer : QAM
Description : Which edges of the pulse can be modulated in pulse duration modulation?
Last Answer : Either, or both at the same time.
Description : The amplifiers following the modulated stage in a low level modulation AM system be (A) linear amplifier (B) harmonic generators (C) class C power amplifiers (D) class untuned amplifiers
Last Answer : The amplifiers following the modulated stage in a low level modulation AM system be class C power amplifiers
Description : What is the full form of 'AM' regarding radio broadcasting? (1) Amplitude Movement (2) Anywhere Movement (3) Amplitude Matching (4) Amplitude Modulation
Last Answer : (4) Amplitude Modulation Explanation: AM broadcasting is the process of radio broadcasting using amplitude modulation. AM was the first method of impressing sound on a radio signal and is still ... frequency. It then amplifies changes in the signal voltage to drive a loudspeaker or earphones.
Description : What is the full form of ‘AM’ regarding radio broadcasting? (1) Amplitude Movement (2) Anywhere Movement (3) Amplitude Matching (4) Amplitude Modulation
Last Answer : Amplitude Modulation
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 : 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 : What is the effect in over modulated amplitude modulated radio broadcasting transmission? A. Interference to adjacent channel B. Higher fidelity C. Increase noise D. Higher audio signal
Last Answer : A. Interference to adjacent channel
Description : The series of periodically recurrent pulses is modulated in amplitude by the corresponding instantaneous samples. A. PFM B. PWM C. PDM D. PAM
Last Answer : D. PAM