26. In a radio receiver, the local oscillator is tuned to a frequency
27. Which of the following oscillator is generally not used at VHF?
28. 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 input resistance of the detector is
29. The output of a diode detector contains
30. Which of the following noise does not occur in transistors?
31. Noise generated in a resistor is also known as
32. Which of the following is used to provide tracking between RF amplifier and local oscillator stages of receiver?
33. The selectivity of a radio receiver is
34. If the intermediate frequency of a superheterodyne receiver falls within the tuning range of the receiver
35. EM 84 tube is used in radio receivers as
36. Which of the following statement about receivers is false?
37. Modulated carrier power in FM
38. In superheterodyne receivers, the local oscillator is used to
39. Which of the following is same in AM and FM receivers?
40. A notch filter is sometimes used in communication receivers to
41. Which one of the following is not a useful quantity for comparing the noise performance of receivers?
42. Which of the following statement about the amplitude limiter is not valid?
43. Noise limiter is provided on AM receivers to
44. A low ratio of the A.C. load impedance of a diode detector results in
45. A trimmer is basically a
46. In a radio receiver
47. Which curve represents the fidelity curve of a standard receiver?
48. The sensitivity of a superheterodyne receiver is determined by
49. In radio receiver, the maximum contribution to noise is from