BSNL TTA Communication MCQ Part Two

BSNL TTA Communication MCQ Part Two

NOTE-NO OF QUESTIONS 115
ANSWER KEY-Correct answer is indicated by symbol (V) in options.
HINTS-In some questions options E-HINTS is indicating the hints of answer
SAMPLE QUESTIONS AND ANSWER

1) The VLF, LF and MF antennas are
A [ ]) horizontally polarized
B [v]) vertically polarized
C [ ]) non linearly polarized
D [ ]) either (a) or (b)

2) If carrier is modulated by a digital bit stream having one of the possible phases of 0°, 90°, 180°, and 270°, then modulation is called
A [ ]) BPSK
B [v]) QPSK
C [ ]) QAM
D [ ]) MSK

3) Johnson noise
A [v]) white for all Practical application
B [ ]) always white
C [ ]) depends on temperature
D [ ]) never white

BSNL TTA Communication MCQ Part Two

4) The number of repeaters in a coaxial cable link depends on
A [v]) system bandwidth
B [ ]) separation of equalizers
C [ ]) the number of coaxial cables in the tube
D [ ]) none of the above

5) The overall noise temperature Te, absolute temperature T and noise figure F are related as
A [v]) Te = T(F – 1)
B [ ]) Te = F(T – 1)
C [ ]) T = Te(F – 1)
D [ ]) Te = (T)(F)

6) By the use of which of the following the PPM can be converted to PWM?
A [ ]) A stable multivibrator
B [ ]) Integrator
C [ ]) Monostable multivibrator
D [v]) Bistable Multivibrator

BSNL TTA Communication MCQ Part Two

7) When a signal is quantized such that the step size S is small in comparison with the peak to peak range of the signal, the mean square quantization error is equal to
A [ ]) S²
B [ ]) S²/2
C [ ]) S²/6
D [v]) S²/12

8) FM has
A [ ]) two sidebands only
B [ ]) four sidebands only
C [ ]) four sidebands only
D [v]) infinite sidebands

9) Image frequency rejection mainly depends upon
A [v]) detector
B [ ]) mixer
C [ ]) IF
D [ ]) RF

10) Frequency frogging is used in a carrier system to
A [ ]) conserve frequencies
B [ ]) reduce distortion
C [v]) reduce cross talk
D [ ]) none of the above

BSNL TTA Communication MCQ Part Two