Q. Figure shows the arrangement of

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Q. Noise figure is defined as

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Q. If N is the number of binary digits needed to assign individual binary code designations to the M quantization levels, the signal to quantization noise ratio S0/Nq in PCM is

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Q. If Vs is signal voltage, Vn is noise voltage, signal to noise ratio S/N is defined as

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Q. The PDF of a Gaussian random variable X is given by following equation. The probability of the event {X = 4} is

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Q. A single tone modulating signal Vm cos ωt modulates a carrier A cos ωct. The carrier power (modulated) and side band powers are respectively

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Q. Modulation index of a AM wave is measured using oscilloscope. The display on the CRO is as shown in figure it can be concluded that

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Q. If f is frequency and d is distance, path attenuation a between isotropic antennas is given by

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Q. If the transmitted pulse power of a radar is Pt (peak value) and the antenna is isotropic, the power density at a distance r is

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Q. In delta modulation, the output signal to quantization noise ratio S0/Nq is (N is the number of bits)

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Q. If B is channel bandwidth, S is signal power and N is the total noise within the channel bandwidth, the channel capacity C of a white band limited gaussian channel is

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Q. For an RC low pass filter, the relation between noise bandwidth BN and 3-dB bandwidth B3dB is

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Q. The block diagram of AM transmitter in which high level modulation is used as shown in figure. The block X could be

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Q. When E1, E2, E3 etc. are the simultaneous modulating voltages, then the total modulating voltage Et will be

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Q. The constellation diagram of a modem has four states as shown in the figure given below. What is the bit rate of this modem?

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Q. What is the RF amplifier plate voltage when the audio-modulating voltage is +600 V?

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Q. If carrier power is P and amplitude modulation index is m, the total power after modulation is

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Q. In figure the output v(t) is

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Q. Efficiency of general AM signal with em = E₁ cos ω₁t + E₂ cos ω₂ tj ec = Ec cos ωct; E₁ cos ω₁t with modulation index m₂ is __________ .

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Q. Each of the following equation expressing decibel gain is correct except

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