This set of Analog Communications Multiple Choice Questions & Answers (MCQs) focuses on “Frequency Discrimination Method”.
1. FM and PM are two ways of angle modulation.
a) True
b) False
View Answer
Explanation: In angle modulation, phase or frequency of the carrier is varied with respect to the transmitting signal.
2. FM transmitting and receiving equipment is __________ as compared to AM equipment.
a) costly
b) cheaper
c) almost equally costly
d) available with ease
View Answer
Explanation: Frequency transmitting and receiving equipment is generally costly when compared to amplitude modulated equipment.
3. Which one of the following is analog?
a) PCM
b) PWM
c) Delta modulation
d) Differential PCM
View Answer
Explanation: Pulse code modulation (PCM), Differential pulse code modulation (DPCM), and Delta modulation comes under digital modulation. Only the PCM comes under analog communication.
4. Schmitt trigger is used to generate PDM.
a) True
b) False
View Answer
Explanation: Pulse density modulation (PDM) is used to represent an analog signal with a binary signal. For generating PDM, monostable multi-vibrator is used.
5. Which of the following is used to generate PDM?
a) Monostable multi-vibrator
b) Free running multi-vibrator
c) Either monostable of free running multi-vibrator
d) JK flip-flop
View Answer
Explanation: Pulse density modulation (PDM) is used to represent an analog signal with a binary signal. For generating PDM, monostable multi-vibrator is used.
6. In case of FM, if the modulating frequency is lowered and the modulating voltage remains constant then the amplitude of distant sidebands decreases.
a) True
b) False
View Answer
Explanation: If the modulating frequency in FM lowered and the modulating voltage remains constant then the amplitude of distant sidebands increases.
7. Skip distance depends on time of day and angle of incidence.
a) True
b) False
View Answer
Explanation: A skip distance is the distance between the two points where radio waves from a transmitter refracted downwards by different layers of the ionosphere. It basically depends on time of day as well as on angle of incidence.
8. Leak type bias is used in plate modulated amplifier to prevent tuned circuit damping.
a) True
b) False
View Answer
Explanation: Leak bias is mainly used to prevent excessive grid current in plate modulated amplifiers.
9. For telegraphy pulse code modulation (PCM) is widely used.
a) True
b) False
View Answer
Explanation: Frequency Shift Keying (FSK) is used to transmit digital information through discrete frequency changes of a carrier signal. It is mainly used for telegraphy.
10. DVD uses laser beam for recording and video head for playback.
a) True
b) False
View Answer
Explanation: Digital Versatile Disc (DVD) uses laser beam for both recording and playback.
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.
