Radio Receivers Questions

• In a broadcast superheterodynes receiver having no RF amplifier, the loaded Q of the antenna coupling circuit is 100. If the intermediate frequency is 455 kHz. In receivers operating upto the limit of shortwave broadcasting the local oscillator often used is
• A communication channel with additive white Gaussian noise, has a bandwidth of 4 kHz and an SNR of 15. Its channel capacity is
• An arbitrary signal m (t) has zero average value and it is bandlimited to 3.2 kHz. It is sampled at the rate of 8 K samples/S. The samples are passed through an ideal bandpass filter with centre frequency of 32 kHz and bandwidth of 6.4 kHz. The output of band pass filter is
• Noise limiter is provided on AM receivers to
• Double spotting in a receiver is due to
• Selectivity varies with receiving frequency, frequency is raised.
• Which curve represents the fidelity curve of a standard receiver?
• The passband of the tuned circuits of a radio receiver should be equal to
• Which of the following circuit cannot be used to demodulate SSB?
• When a superheterodyne receiver is tuned to 455 kHz, its local oscillator provides a mixer with the input at 1010 kHz. The image frequency is
• RF amplifiers are used in radio receivers for
• The selectivity curve of a standard receiver is represented by
• In a receiver, which of the following device has RF input but IF output?
• Fidelity of a receiver represents
• A receiver having an RF amplifier and an IF of 450 kHz, has Q of the coils 65 and an incoming frequency of 1200 kHz. The image rejection of the receiver is
• The source of which of the following noise is different from that of the remaining?
• The sensitivity of a superheterodyne receiver is determined by
• In a superheterodyne receiver, the IF stage has better selectivity than RF stage because
• An unmodulated voltage 10 V effective is applied to a dioxide detector in which load resistance is 4 x 10-5 ohms. A micrometer shows that the rectified DC current in this resistance is 30 A. The efficiency of detection is
• The problem associated with tuned-radio frequency receiver is