This set of Analog Communications Multiple Choice Questions & Answers (MCQs) focuses on “Generation of VSB”.
1. Which of the following oscillator is not found in FM?
a) Hartley Oscillator
b) Crystal Oscillator
c) Armstrong Oscillator
d) Dynatron Oscillator
Explanation: In frequency modulation, frequency of carrier varies with the modulated wave. Crystal oscillator is used to create an electric signal with a precise frequency. But it has no use in frequency modulation.
2. What is the approximated range of audio frequencies?
a) 20Hz to 20KHz
b) 20Hz to 200KHz
c) 10Hz to 10KHz
d) 20Hz to 20MHz
Explanation: The standard fixed range of audio frequencies is from 20HZ to 20 KHz.
3. What is duty cycle?
a) ratio of time on to time off
b) ratio of time off to time on
c) 1⁄2 × (ratio of time on to time off)
d) 1⁄2 × (ratio of time off to time on)
Explanation: Duty cycle is the fraction of one period in which the system is active. It can also be defined as the ratio of time on to time off of a system.
4. Which of the following is used for demodulation of PAM signal?
a) a band reject filter
b) a band pass filter
c) a low pass filter
d) a high pass filter
Explanation: Pulse Amplitude Modulation is the transmission of data by varying the amplitude of different pulses. A low pass filter is always used when we have to demodulate it.
5. Which of the following is not a part of analogue communication?
Explanation: Pulse code modulation (PCM) is a digital form of communication. It has no relation with analogue communication.
6. For demodulation of PCM, it is first converted into ________
Explanation: Pulse code modulation (PCM) is a digital form of communication. For demodulation of PCM, it is necessary to convert it into PAM.
7. There is no requirement of IF amplifier stages for a video monitor.
Explanation: Video amplifier is used to amplify video signals before passing them to a Cathode ray tube. And there is no need of IF amplifier stages for a video monitor.
8. Inherently most noise resistant modulating system is _________
Explanation: Noise is an unwanted signal that causes disturbance. Generally most of the PCM system are noise resistant.
9. Which of the following modulation is used for radio navigation?
a) Pulse Modulation
b) Amplitude Modulation
c) Phase Modulation
d) Frequency Modulation
Explanation: In pulse modulation, message information is encoded in the amplitude of series of signal pulse. It is mostly used for radio navigation and for many others.
10. Frequency modulated broadcast band generally lies in ________
Explanation: VHF (very high frequency) is the ITU designation for the range of radio frequency from 30 to 300MHz. Frequency modulated broadcast band generally lies in it only.
Sanfoundry Global Education & Learning Series – Analog Communications.
To practice all areas of Analog Communications, here is complete set of 1000+ Multiple Choice Questions and Answers.