Both frequency and phase modulation utilize ________ modulation A. Phase B. AM and FM C. Digital D. Angle

Both frequency and phase modulation utilize ________ modulation
A. Phase
B. AM and FM
C. Digital
D. Angle
by

1 Answer

Answer :

D. Angle
by

Related questions

What modulation is normally used with digital data? A. AM B. FM C. SSB D. QPSK

Description : What modulation is normally used with digital data? A. AM B. FM C. SSB D. QPSK

Last Answer : D. QPSK

What is the deviation ratio for an FM-phone signal having a maximum frequency swing of plus or minus 5 kHz and accepting a maximum modulation rate of 3kHz? A. 60 B. 0.16 C. 0.6 D. 1.66

Description : What is the deviation ratio for an FM-phone signal having a maximum frequency swing of plus or minus 5 kHz and accepting a maximum modulation rate of 3kHz? A. 60 B. 0.16 C. 0.6 D. 1.66

Last Answer : D. 1.66

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.

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.

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

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

What type of modulation is used on voice and video signals? A. AM B. FM C. SSB D. QPSK

Description : What type of modulation is used on voice and video signals? A. AM B. FM C. SSB D. QPSK

Last Answer : B. FM

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

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

The modulation technique used by GSM cellular system A. Phase shift keying B. Frequency shift keying C. Gaussian minimum shift keying D. QAM

Description : The modulation technique used by GSM cellular system A. Phase shift keying B. Frequency shift keying C. Gaussian minimum shift keying D. QAM

Last Answer : C. Gaussian minimum shift keying

What is the difference between phase and frequency modulation? A. Is purely theoretical because they are the same in practice B. Lies in poorer audio response of phase modulation C. Lies in the different definitions of the modulation index D. Is too great to make two systems compatible

Description : What is the difference between phase and frequency modulation? A. Is purely theoretical because they are the same in practice B. Lies in poorer audio response of phase modulation C. Lies in the different definitions of the modulation index D. Is too great to make two systems compatible

Last Answer : C. Lies in the different definitions of the modulation index

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 same bandwidth. A. Reference audio output B. None of these C. Audio frequency response D. Residual noise level

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

Compare narrow band FM with wide-band FM w.r.t. following points. (i) Modulation index (ii) Maximum deviation (iii)Range of modulating frequency (iv)Application

Description : Compare narrow band FM with wide-band FM w.r.t. following points. (i) Modulation index (ii) Maximum deviation (iii)Range of modulating frequency (iv)Application

Last Answer : Sr. No Parameters Narrow band FM Wide band FM 1 Modulation index Less than or slightly greater than 1 Greater than 1  2 Maximum deviation ... like police wireless, ambulance etc. Entertainment broadcasting can be used for high quality music transmission 

An FM signal with modulation index mƒ is passed through a frequency tripler. The modulation index of the

Description : An FM signal with modulation index mƒ is passed through a frequency tripler. The modulation index of the output signal will be (1) mƒ (2) 3mƒ (3) 9mƒ (4) 27mƒ

Last Answer : An FM signal with modulation index mƒ is passed through a frequency tripler. The modulation index of the output signal will be 3mƒ

The modulation index of a FM Signal having modulating frequency 2 KHz and Max deviation is 10 KHz, is: -

Description : The modulation index of a FM Signal having modulating frequency 2 KHz and Max deviation is 10 KHz, is: -  a) 2 b) 5 c) 3 d) 4

Last Answer : The modulation index of a FM Signal having modulating frequency 2 KHz and Max deviation is 10 KHz, is: - 5

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

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

Digital modulation technique used in modems. A. ASK B. PSK C. FSK D. All of these

Description : Digital modulation technique used in modems. A. ASK B. PSK C. FSK D. All of these

Last Answer : B. PSK

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

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

What is the approximate bandwidth of an FM system with 10 kHz of modulating frequency and a 150 kHz of frequency deviation? A. 300 kHz B. 320 kHz C. 150 kHz D. 200 kHz

Description : What is the approximate bandwidth of an FM system with 10 kHz of modulating frequency and a 150 kHz of frequency deviation? A. 300 kHz B. 320 kHz C. 150 kHz D. 200 kHz

Last Answer : B. 320 kHz

An FM receiver whose intermediate frequency is 10.7 MHz, is experiencing image channel interference from a station transmitting on 121.1 MHz. If the local oscillator is tracking above, the receiver is tuned to A. 131.8 MHz B. 110.4 MHz C. 142.5 MHz D. 99.7 MHz

Description : An FM receiver whose intermediate frequency is 10.7 MHz, is experiencing image channel interference from a station transmitting on 121.1 MHz. If the local oscillator is tracking above, the receiver is tuned to A. 131.8 MHz B. 110.4 MHz C. 142.5 MHz D. 99.7 MHz

Last Answer : D. 99.7 MHz

What is a frequency discriminator? A. A circuit for filtering two closely adjacent signals B. A circuit for detecting FM signals C. An FM generator D. An automatic bandswitching circuit.

Description : What is a frequency discriminator? A. A circuit for filtering two closely adjacent signals B. A circuit for detecting FM signals C. An FM generator D. An automatic bandswitching circuit.

Last Answer : B. A circuit for detecting FM signals

The frequency spectrum of the stereophonic FM signal. A. 67 kHz B. 59.5 to 74.5 kHz C. 19 to 38 kHz D. 30 to 53 kHz

Description : The frequency spectrum of the stereophonic FM signal. A. 67 kHz B. 59.5 to 74.5 kHz C. 19 to 38 kHz D. 30 to 53 kHz

Last Answer : D. 30 to 53 kHz

A particular circuit that rids FM of noise A. Detector B. Discriminator C. Phase Shifter D. Limiter

Description : A particular circuit that rids FM of noise A. Detector B. Discriminator C. Phase Shifter D. Limiter

Last Answer : D. Limiter

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

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

What particular circuit that rids FM of noise? A. HPF B. Phase shifter C. Limiter D. LPF

Description : What particular circuit that rids FM of noise? A. HPF B. Phase shifter C. Limiter D. LPF

Last Answer : C. Limiter

AM and FM are examplesof ________ conversion. A) digital-to-digital B) digital-to-analog C) analog-to-analog D) analog-to-digita

Description : AM and FM are examplesof ________ conversion. A) digital-to-digital B) digital-to-analog C) analog-to-analog D) analog-to-digita

Last Answer : analog-to-analog

Which of the following antennas is used for testing and adjusting a transmitter for proper modulation, amplifier operation and frequency accuracy? A. Elementary B. Real C. Isotropic D. Dummy

Description : Which of the following antennas is used for testing and adjusting a transmitter for proper modulation, amplifier operation and frequency accuracy? A. Elementary B. Real C. Isotropic D. Dummy

Last Answer : D. Dummy

Why are frequency modulation transmitters more efficient? A. Because their power is increased by class C amplifiers B. Because their power is increased by class A amplifiers C. Because their power is increased by class B amplifiers D. Because their power is increased by class AB amplifiers

Description : Why are frequency modulation transmitters more efficient? A. Because their power is increased by class C amplifiers B. Because their power is increased by class A amplifiers C. Because their power is increased by class B amplifiers D. Because their power is increased by class AB amplifiers

Last Answer : A. Because their power is increased by class C amplifiers

What is the term used to describe a spread spectrum communications system where the center frequency if a conventional carrier is altered many time per second in accordance with a pseudo-random list of channels? A. Frequency hopping B. Direct sequence C. Time-domain frequency modulation D. Frequency compandored spread spectrum

Description : What is the term used to describe a spread spectrum communications system where the center frequency if a conventional carrier is altered many time per second in accordance with a pseudo ... hopping B. Direct sequence C. Time-domain frequency modulation D. Frequency compandored spread spectrum

Last Answer : A. Frequency hopping

In modulation technique, which of the following is referred to audible pitch? A. Width B. Frequency C. Harmonic D. Amplitude

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

What is meant by the term deviation ratio? A. The ratio of the carrier center frequency to the audio modulating frequency B. The ratio of the highest audio modulating frequency to the average audio modulating frequency C. The ratio of the maximum carrier frequency deviation to the highest audio modulation frequency D. The ratio of the audio modulating frequency to the center carrier frequency

Description : What is meant by the term deviation ratio? A. The ratio of the carrier center frequency to the audio modulating frequency B. The ratio of the highest audio modulating frequency to the ... audio modulation frequency D. The ratio of the audio modulating frequency to the center carrier frequency

Last Answer : C. The ratio of the maximum carrier frequency deviation to the highest audio modulation frequency

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

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

It is an average power of a radio transmitter supplied to the antenna transmission line taken during a long sufficient interval of time and compared with the lowest frequency encountered in the modulation, taken under the normal operating conditions. A. Carrier power B. Rated power C. Mean power D. Peak envelop power

Description : It is an average power of a radio transmitter supplied to the antenna transmission line taken during a long sufficient interval of time and compared with the lowest frequency encountered in the modulation ... operating conditions. A. Carrier power B. Rated power C. Mean power D. Peak envelop power

Last Answer : C. Mean power

One of the following is not among the advantages of series modulation A. No transformer B. Suppressed white noise C. Simple.D. Modulates any frequency

Description : One of the following is not among the advantages of series modulation A. No transformer B. Suppressed white noise C. Simple D. Modulates any frequency

Last Answer : B. Suppressed white noise

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

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

Referred to as an average power from the radio transmitter supplied to the antenna transmission line taken during one radio frequency cycle under no modulation. A. Carrier power B. Rated power C. Peak envelop power D. Mean power

Description : Referred to as an average power from the radio transmitter supplied to the antenna transmission line taken during one radio frequency cycle under no modulation. A. Carrier power B. Rated power C. Peak envelop power D. Mean power

Last Answer : A. Carrier power

Used for time division multiplexing. A. Frequency modulation B. Pulsed modulation C. SSB 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

Average power of a radio transmitter supplied to the antenna transmission line by a transmitter during one radio frequency cycle taken under the condition of no modulation. A. Peak envelop power B. Rated power C. Carrier power D. Mean power

Description : Average power of a radio transmitter supplied to the antenna transmission line by a transmitter during one radio frequency cycle taken under the condition of no modulation. A. Peak envelop power B. Rated power C. Carrier power D. Mean power

Last Answer : C. Carrier power

Emission on a frequency or frequencies immediately outside the necessary bandwidth which result from the modulation process except spurious emission. A. Radiation B. Noise C. Out of the band D. Interference

Description : Emission on a frequency or frequencies immediately outside the necessary bandwidth which result from the modulation process except spurious emission. A. Radiation B. Noise C. Out of the band D. Interference

Last Answer : C. Out of the band

A good example of a pilot tone system used in commercial frequency modulation stations. A. FDM B. Time division C. Stereo multiplexing D. Frequency modulation

Description : A good example of a pilot tone system used in commercial frequency modulation stations. A. FDM B. Time division C. Stereo multiplexing D. Frequency modulation

Last Answer : C. Stereo multiplexing

What is the main purpose of a communications system? A. None of these B. To have a frequency assignment C. For modulation D. To provide an acceptable replica of the information at the destination

Description : What is the main purpose of a communications system? A. None of these B. To have a frequency assignment C. For modulation D. To provide an acceptable replica of the information at the destination

Last Answer : D. To provide an acceptable replica of the information at the destination

ECE Board Exam March 1996 The modulation system used for telegraphy is A. frequency-shift keying B. two-tone modulation C. pulse-code modulation D. single-tone modulation

Description : ECE Board Exam March 1996 The modulation system used for telegraphy is A. frequency-shift keying B. two-tone modulation C. pulse-code modulation D. single-tone modulation

Last Answer : A. frequency-shift keying

Give the expression for modulation index for AM and FM.

Description : Give the expression for modulation index for AM and FM.

Last Answer : 1.Modulation index for AM ma=Vm / Vc Where Vm is modulating voltage Vc is the carrier voltage 2.Modulation index for FM mf=δ /fm where δ is the deviation fm is the modulating frequency

Differentiate between AM and FM on the basis of: (i) Definition (ii) Bandwidth (iii) Modulation Index (iv) Application

Description : Differentiate between AM and FM on the basis of: (i) Definition (ii) Bandwidth (iii) Modulation Index (iv) Application

Last Answer : Compare AM and FM on the basis of i)Definition ii)Bandwidth iii) Wave propogation iv)Number of sidebands

Compare AM with FM with respect to following points: a) Definition. b) Modulation index. c) Bandwidth. d) Side band.

Description : Compare AM with FM with respect to following points: a) Definition. b) Modulation index. c) Bandwidth. d) Side band.

Last Answer : Parameters AM FM Definition It is the process in which the amplitude of carrier signal is varied in accordance with the instantaneous value of modulating signal keeping frequency and ... frequency deviation. Side band There are two sidebands Infinite number of sideband

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 the amplitudeof the information signal changes, thefrequency of thecarrier changes correspondingly. A) AM B) PM C) FM D) none of the above

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

Which does not use vertical polarization antenna? A. AM Broadcasting B. FM Broadcasting C. Mobile Communications D. Satellite Communications

Description : Which does not use vertical polarization antenna? A. AM Broadcasting B. FM Broadcasting C. Mobile Communications D. Satellite Communications

Last Answer : B. FM Broadcasting

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

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

With which emission type is the capture-effect most pronounced? A. CW B. FM C. SSB D. AM

Description : With which emission type is the capture-effect most pronounced? A. CW B. FM C. SSB D. AM

Last Answer : B. FM

The final amplifier of either FM or AM transmitter operates as A. Class B B. Class C C. Class A D. Class D

Description : The final amplifier of either FM or AM transmitter operates as A. Class B B. Class C C. Class A D. Class D

Last Answer : B. Class C

The antenna current is doubled when the modulation index is doubled in ______ AM system. A. A5C B. A3J C. A3 D. A3H

Description : The antenna current is doubled when the modulation index is doubled in ______ AM system. A. A5C B. A3J C. A3 D. A3H

Last Answer : B. A3J

An AM transmitter is rated 100W at 100% modulation. How much power required for the carrier? A. 33.33 W B. 66.66 W C. 83.33 W D. 100 W

Description : An AM transmitter is rated 100W at 100% modulation. How much power required for the carrier? A. 33.33 W B. 66.66 W C. 83.33 W D. 100 W

Last Answer : B. 66.66 W

If the modulation index of an AM wave is doubled, the antenna current is also doubled, the AM system being used is A. A5C B. A3J C. A3H D. A3

Description : If the modulation index of an AM wave is doubled, the antenna current is also doubled, the AM system being used is A. A5C B. A3J C. A3H D. A3

Last Answer : B. A3J