71. Companding is used :
(a) To protect small signals in PCM from quantizing distortion
(b) To overcome quantize noise in PCM
(c) To overcome impulse noise
(d) None of these
72. FM discriminator changes the FM signal into :
(a) AM signal
(b) FM signal
(c) PM signal
(d) None of these
73. Which of the following system is digital :
(a) Pulse Position Modulation
(b) Pulse Code Modulation
(c) Pulse Width Modulation
(d) Pulse Frequency Modulation
74. In communication system, sampling technique leads to :
(a) Cheaper equipment
(b) Better efficiency
(c) Higher speed of communication
(d) Simpler operation
75. Frequency Shift Keying is basically a method involving :
(a) Amplitude Modulation
(b) Frequency Modulation
(c) Phase Modulation
(d) None of these
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