Q. A sinusoidal voltage amplitude modulates a carrier of peak value 5 kV. Each side band has an amplitude of 500 V. The modulation index is

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Q. Kell factor is about

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Q. AM amplifier having noise figure of 20 dB and available power gain of 15 dB is followed by a mixer circuit having noise figure of 9 dB. The overall noise figure as referred to input in dB is

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Q. Which one of the following is non-resonant antenna?

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Q. The efficiency of using a binary system for selection of 1 out of 13 equally probable events is

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Q. The most suitable method for detecting a modulated signal g(t) = (3 to 6 cos 2πfmt) cos 2πfct is

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Q. A total of 16 equally probable events exist. If it is required to select one out of them, the number of required bits is

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Q. When modulation index of an AM wave is increased from 0.5 to 1, the transmitted power

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Q. Quantizing error occurs in

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Q. In audio cassettes the width of each recording track is

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Q. The most commonly used transistor amplifier circuit is

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Q. When energy is fed into open wire transmission line the energy may get dissipated due to

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Q. Loudness control gives

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Q. A mobile telephone has a range of about

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Q. If transmitted power is 75 kW, the field strength at 30 km distance will be about

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Q. The time required for horizontal blanking is 16% of that for each horizontal line. If horizontal time is 63.5 μs, the horizontal blanking time for each line is about

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Q. When the number of quantising levels is 16 in PCM, the number of pulses in a code group will be

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Q. A message signal with bandwidth 10 kHz is lower sideband SSB modulated with carrier frequency fc1 = 10⁶ Hz. The resulting signal is then passed though a narrow band frequency modulator with carrier frequency fc2 = 10⁹ Hz. The bandwidth of the output would be

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Q. In a PCM system, if the code word length is increased from 6 to 8 bits, the signal to quantization noise ratio improves by the factor.

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Q. For 10 bit PCM system, the signal to quantization noise ratio is 62 dB. If the number of bits is increased by 2, then the signal to quantization noise ratio will

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