Deck 2: Communication and Radio Broadcasting

Question 1

The _____________speech is also called as reported speech

A)direct
B)indirect
C)indefinite
D)definite

Answer 1

indirect

Question 2

For attenuation of high frequencies we should use

A)shunt capacitance
B)series capacitance
C)inductance
D)resistance

Answer 2

shunt capacitance

Question 3

A modem is classified as low speed if data rate handled is

A)upto 100 bps
B)upto 250 bps
C)upto 400 bps
D)upto 600 bps

Answer 3

upto 600 bps

Question 4

VSB modulation is preferred in TV because

A)it reduces the bandwidth requirement to half
B)it avoids phase distortion at low frequencies
C)it results in better reception
D)none of the above

Question 5

A woofer should be fed from the input through a

A)low pass filter
B)high pass filter
C)band pass filter
D)band stop filter

Question 6

When the length of antenna is a whole wavelength

A)the radiation at right angles is zero
B)the radiation at right angles is maximum
C)the radiation is zero in all directions
D)the radiation is maximum in all directions

Question 7

Circular polarization

A)is useful in reducing depolarization effect on received wave
B)involves critical alignment of transmitting and receiving antenna
C)is useful in discrimination between reception of adjacent beams
D)none of the above

Question 8

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

A)102.3
B)113
C)70.2
D)80.9

Question 9

For telegraphy the most commonly used modulation system is

A)fsk
B)two tone modulation
C)pcm
D)single tone modulation

Question 10

Commercial Frequency deviation of FM is

A)70 khz
B)75 khz
C)80 khz
D)65 khz

Question 11

The colour of an object is decided by

A)the reflected colour
B)the wavelength transmitted through it
C)reflected colour for opaque object and wavelength transmitted through it for transparent objects
D)none of the above

Question 12

In Pulse Code Modulation system

A)large bandwidth is required
B)quantising noise can be overcome by companding
C)quantising noise can be reduced by decreasing the number of standard levels
D)suffers from the disadvantage of its incompatibly with tdm

Question 13

Which of the following statements is correct?

A)convex lens has positive focal power and concave lens have negative focal power
B)convex lens has negative focal power and concave lens have positive focal power
C)all lens have positive focal power
D)all lens have negative focal power

Question 14

In Modulation, "carrier" is

A)resultant wave
B)speech voltage to be transmitted
C)voltage with constant frequency, phase or amplitude
D)voltage for which frequency, phase or amplitude is varied

Question 15

To eliminate ghosts in the picture

A)use a longer transmission line
B)connect a booster
C)change the antenna orientation of location
D)twist the transmission line

Question 16

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

A)low frequency
B)medium frequency
C)high frequency
D)very high frequency

Question 17

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

A)stepped index operation
B)impurities
C)microbending
D)attenuation in glass

Question 18

A telephone channel requires a bandwidth of about

A)1 khz
B)3 khz
C)10 khz
D)50 khz

Question 19

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

A)1
B)0.8
C)0.5
D)0

Question 20

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

A)zero capacity
B)infinite capacity
C)small capacity
D)none of the above

Question 21

DVD uses

A)laser beam for both recording and playback
B)laser beam for recording and video head for playback
C)video head for recording and laser beam for playback
D)none of the above

Question 22

Fourier analysis indicate that a square wave can be represented as

A)a fundamental sine wave and odd harmonics
B)a fundamental sine wave and even harmonics
C)a fundamental sine wave and harmonics
D)fundamental and subharmonic sine waves