Explore topic-wise MCQs in Engineering.

Under ordinary circumstances, impulse noise can be reduced in

FM transmitting and receiving equipment as compared to AM equipment is

If output power of a radio receiver is doubled, its volume is increased by __________ dB.

To eliminate ghosts in the picture

The frequency range of 300 kHz to 3000 kHz is known as

Assertion (A): In FM the frequency of the carrier is varied by the modulating voltage

Reason (R): FM and PM are two forms of angle modulation.

For telegraphy the most commonly used modulation system is

For a low level AM system, the amplifiers modulated stage must be

Which of the following does not cause losses in optical fibre cables?

Commercial Frequency deviation of FM is

The colour of an object is decided by

In Pulse Code Modulation system

Waveform shown in figure is that for

The disadvantage of FM over AM is that

Which of the following is a digital modulation technique?

If in a broadcasting studio, a 1000 kHz carrier is modulated by an audio signal of frequency range 100-5000 kHz, the width of channel is __________ kHz.

Which one of the following is analog?

Which of the following is used to generate PDM?

A zero mean white Gaussian noise is passed through an ideal low pass filter of bandwidth 10 kHz. The output of the samples so obtained would be

What is the purpose of peak clipper circuits in radio transmitters?

In case of frequency modulation, modulating voltage remains constant if the modulating frequency is lowered, then

If sampling is done at the rate of 10 kHz. The bandwidth required is

It is found that a ship to ship communication suffers from fading. This can be avoided by using

Full duplex operation-permits transmission in both directions at the same time.

In a TV receiver antenna the length of reflector rod

The modulation index of an FM is changed from 0 to 1. How does the transmitted power change?

For AM receivers the standard IF frequency is

The rate at which information can be carried through a communication channel depends on

Some types of traps used in video IF amplifier of colour TV are

Direct and reflected sound waves may interfere with each other.

A carrier is simultaneously modulated by two sine waves having modulation indices of 0.4 and 0.3. The total modulation index will be

Which of the following is an indirect way of generating FM?

A 1000 kHz carrier is simultaneously modulated with 300 Hz, 800 Hz and 2 kHz audio sine waves. Which of the following frequency is least likely to be present in the output?

In radar systems PRF stands for

Circular polarization

An FM radio receiver which is tuned to a 91.6 MHz broadcast station may receive an image frequency of __________ MHz.

When the length of antenna is a whole wavelength

A 400 W carrier is amplitude modulated with m = 0.75. The total power in AM is

For a given carrier wave, maximum undistorted power is transmitted when value of modulation is

A telephone channel requires a bandwidth of about

As per Shannon-Hartley theorem, a noise less Gaussian channel has

DVD uses

Fourier analysis indicate that a square wave can be represented as

If the target cross-section is changing, the best scanning system for accurate tracking is

Audio systems use transverse recording.

If e = 10 sin(10⁸ t + 3 sin 10⁴ t) then the modulation index is

Frequency modulation consists in

How can the quantizing noise be reduced?

In high power AM transmission, modulation is done at

In a CD player the laser uses