51. In a 8 bit counter type Analog to Digital converter which is driven by 500 kHz clock. The maximum conversion time will be:


(a) 542 𝜇s

(b) 524 𝜇s

(c) 512 𝜇s

(d) 484 𝜇s

Answer: (c)

52. The number of input gates required to realize the following expression,


will be:

(a) 13

(b) 14

(c) 15

(d) 16

Answer: (c)

53. The simplified expression of:


will be:



Answer: (a)

54. A computer has a 2 𝑀 memory. The decimal equivalent of 2 𝑀 will be:


(a) 2,000 000

(b) 2,048,546

(c) 2,097,152

(d) 2,194,304

Answer: (c)

55. 


Answer: (a)

56. A receiver connected to an antenna whose resistance is 50 Ω has equivalent noise resistance of 30 Ω. The receiver’s noise figure in decibels will be:


(a) 1.6

(b) 2.6

(c) 3.2

(d) 4.2

Answer: (a)

57. A broadcast radio transmitter radiates 10 kW when modulation is 60 %. The carrier power will be nearly:


(a) 32.5 𝑘W

(b) 24.5 𝑘W

(c) 16.5 𝑘W

(d) 8.5 𝑘W

Answer: (d)

58. When the carrier and one of the sidebands are suppressed in an AM wave modulated to a depth of 100 %, the power saving will be nearly:


(a) 73 %

(b) 78 %

(c) 81 %

(d) 83 %

Answer: (d)

59. Which one of the following demodulators is widely used in high quality FM radio receivers?


(a) FM Feedback

(b) Phase-locked loop

(c) Foster-Seeley discriminator

(d) Extension

Answer: (c)

60. In an automatic frequency control of a receiver the feedback for 𝐴𝐴𝐴 is taken from:


(a) Detector stage

(b) Mixer stage

(c) Local oscillator

(d) LF IF amplifier

Answer: (d)