This set of Analog Communications Multiple Choice Questions & Answers (MCQs) focuses on “ZCD”.
1. For Amplitude Modulation, Emitter modulator ________
a) Operates in class C mode
b) Has a low efficiency
c) Output power is high
d) Operates in class B mode
Explanation: Emitter Modulator operates in class A region. It has a very low efficiency. The output power is low so for modulation at high level, it is not suitable.
2. MAU stands for __________
a) Multiple Access Unit
b) Multi-station Access Unit
c) Multiple Auxiliary Unit
d) Multi-station Access Unit
Explanation: MAU stands for Multi-station Access Unit. It acts as a hub that connects a group of computers to a token ring local area network.
3. Packet switching is based on ________
a) switched circuits
b) un-switched circuits
d) real time delivery
Explanation: Packet switching is a method of grouping data transmitted over a network into packets. It is based on store and forward algorithm.
4. What is used for setting up a virtual circuit?
Explanation: For creation of any virtual circuit, a network is must required.
5. Which modulation is used in high frequency radio-teletype systems?
Explanation: Frequency Shift Keying is a type of frequency modulation. In it data is transmitted through discrete frequency changes of a carrier signal. It is highly used in frequency radio-teletype systems.
6. When we use TDMA instead of TDM?
a) when signals come from different sources
b) when all the signals come from same source
c) when all the signals contain the same information
d) when there is RF communication
Explanation: If all the signals comes from different types of sources, then it is better to use TDMA instead of TDM.
7. The effect of frequency on the resistance of a wire is called ________
a) skin effect
b) I2R loss
c) ohmic effect
d) threshold effect
Explanation: Skin effect becomes more and more apparent as frequency increases. It is the effect of frequencies on the resistance of a wire.
8. The electric and magnetic field of a radio wave are perpendicular to each other.
Explanation: The statement is correct that both fields are perpendicular to each other. They are also perpendicular to the direction of propagation.
9. Which polarization is possible for an electromagnetic wave?
d) can be vertical or horizontal or circular
Explanation: In electromagnetic waves, both electric and magnetic fields are present. Due to which it can be vertically polarized or horizontally or circularly polarized.
10. On which factor dominant mode of a waveguide depends?
c) point of signal injection
Explanation: A waveguide is something that guides waves, such as electromagnetic wave or sound with minimum loss of energy. The dominant mode of a waveguide depends on the shape of the waveguide.
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.