61. The saving in power in a SSB system is :
(a) 100%
(b) 75%
(c) >=75%
(d) 50%
62. De-emphasis circuit is used :
(a) After Modulation
(b) Prior to Modulation
(c) To De-emphasis low frequency components
(d) To De-emphasis high frequency components
63. In a Broadcast Super Heterodyne Receiver :
(a) The RF Amplifier normally works at 455 KHz above the carrier frequency
(b) Mixer input must be tuned to the signal frequency
(c) Local oscillator operates below the signal frequency
(d) Local oscillator frequency is normally double the IF
64. Time Division Multiplex :
(a) Can be used with PCM only
(b) Combines five groups into a super group
(c) Stacks 24 channel in adjacent frequency slots
(d) Interleave pulses belonging to different transmissions
65. The saving in power in DSBSC system modulated at 80% is :
(a) Nil
(b) 80%
(c) 88.3%
(d) 50%
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