Analog Communication System MCQs

Question 1

FM discriminator changes the FM signal into

Accepted Answer

AM signal

Answer

FM signal

Answer

either of the above

Answer

none of the above

Question 2

Which of the following cannot be used to demodulate SSB?

Accepted Answer

Bipolar transistor balanced modulator

Answer

Complete phase shift generators

Answer

Diode balanced modulator

Answer

Product detector

Question 3

Sky wave propagation is used for transmission

Accepted Answer

long distance

Answer

medium distance

Answer

short distance

Answer

mobile

Question 4

The bandwidth requirement for VSB system is the bandwidth for SSB system.

Accepted Answer

same as

Answer

less than

Answer

more than

Answer

double

Question 5

microphone does not have a flat frequency response.

Accepted Answer

Carbon

Answer

Crystal

Answer

Ribbon

Answer

Condenser

Question 6

In case of FM, which of the following statements is not a reason for high signal-to-noise ratio?

Accepted Answer

None of the above

Answer

Interference from other FM transmitter is very less

Answer

(a) There is less noise at frequencies at which FM is used

Answer

Amplitude limiters are incorporated in FM receivers

Question 7

The modulation index of a narrowband FM signal is

Accepted Answer

nearly equal to 1

Answer

much less than 1

Answer

much greater than 1

Answer

40 percent

Question 8

Frequency and phase modulations differ in which of the following?

Accepted Answer

Different definitions of the modulation indices

Answer

their actual waveform

Answer

Compatibility towards each other

Answer

All of the above

Question 9

The threshold effect in demodulators is

Accepted Answer

the rapid fall on output signal to soise ratio when the input signal to noise ratio falls below a particular value

Answer

exhibited by all demodulators when the input signal to noise ratio is low

Answer

the property exhibited by all AM suppressed carrier coherent demodulators

Answer

the property exhibited by correlation receivers