| 51. |
The _____________speech is also called as reported speech |
| A. | direct |
| B. | indirect |
| C. | indefinite |
| D. | definite |
| Answer» B. indirect | |
| 52. |
A cordless telephone using separate frequencies for transmission in base and portable units is known as |
| A. | duplex arrangement |
| B. | half duplex arrangement |
| C. | either (a) or (b) |
| D. | neither (a) nor (b) |
| Answer» A. duplex arrangement | |
| 53. |
For attenuation of high frequencies we should use |
| A. | shunt capacitance |
| B. | series capacitance |
| C. | inductance |
| D. | resistance |
| Answer» A. shunt capacitance | |
| 54. |
A modem is classified as low speed if data rate handled is |
| A. | upto 100 bps |
| B. | upto 250 bps |
| C. | upto 400 bps |
| D. | upto 600 bps |
| Answer» D. upto 600 bps | |
| 55. |
VSB modulation is preferred in TV because |
| A. | it reduces the bandwidth requirement to half |
| B. | it avoids phase distortion at low frequencies |
| C. | it results in better reception |
| D. | none of the above |
| Answer» A. it reduces the bandwidth requirement to half | |
| 56. |
A woofer should be fed from the input through a |
| A. | low pass filter |
| B. | high pass filter |
| C. | band pass filter |
| D. | band stop filter |
| Answer» A. low pass filter | |
| 57. |
Which of the following is an indirect way of generating FM? |
| A. | armstrong modulator |
| B. | varactor diode modulator |
| C. | reactance fet modulator |
| D. | reactance bipolar transistor |
| Answer» A. armstrong modulator | |
| 58. |
When the length of antenna is a whole wavelength |
| A. | the radiation at right angles is zero |
| B. | the radiation at right angles is maximum |
| C. | the radiation is zero in all directions |
| D. | the radiation is maximum in all directions |
| Answer» A. the radiation at right angles is zero | |
| 59. |
Circular polarization |
| A. | is useful in reducing depolarization effect on received wave |
| B. | involves critical alignment of transmitting and receiving antenna |
| C. | is useful in discrimination between reception of adjacent beams |
| D. | none of the above |
| Answer» A. is useful in reducing depolarization effect on received wave | |
| 60. |
An FM radio receiver which is tuned to a 91.6 MHz broadcast station may receive an image frequency of __________ MHz. |
| A. | 102.3 |
| B. | 113 |
| C. | 70.2 |
| D. | 80.9 |
| Answer» B. 113 | |
| 61. |
For telegraphy the most commonly used modulation system is |
| A. | fsk |
| B. | two tone modulation |
| C. | pcm |
| D. | single tone modulation |
| Answer» A. fsk | |
| 62. |
Commercial Frequency deviation of FM is |
| A. | 70 khz |
| B. | 75 khz |
| C. | 80 khz |
| D. | 65 khz |
| Answer» B. 75 khz | |
| 63. |
The colour of an object is decided by |
| A. | the reflected colour |
| B. | the wavelength transmitted through it |
| C. | reflected colour for opaque object and wavelength transmitted through it for transparent objects |
| D. | none of the above |
| Answer» C. reflected colour for opaque object and wavelength transmitted through it for transparent objects | |
| 64. |
In Pulse Code Modulation system |
| A. | large bandwidth is required |
| B. | quantising noise can be overcome by companding |
| C. | quantising noise can be reduced by decreasing the number of standard levels |
| D. | suffers from the disadvantage of its incompatibly with tdm |
| Answer» A. large bandwidth is required | |
| 65. |
Which of the following statements is correct? |
| A. | convex lens has positive focal power and concave lens have negative focal power |
| B. | convex lens has negative focal power and concave lens have positive focal power |
| C. | all lens have positive focal power |
| D. | all lens have negative focal power |
| Answer» A. convex lens has positive focal power and concave lens have negative focal power | |
| 66. |
In Modulation, “carrier” is |
| A. | resultant wave |
| B. | speech voltage to be transmitted |
| C. | voltage with constant frequency, phase or amplitude |
| D. | voltage for which frequency, phase or amplitude is varied |
| Answer» D. voltage for which frequency, phase or amplitude is varied | |
| 67. |
To eliminate ghosts in the picture |
| A. | use a longer transmission line |
| B. | connect a booster |
| C. | change the antenna orientation of location |
| D. | twist the transmission line |
| Answer» C. change the antenna orientation of location | |
| 68. |
The frequency range of 300 kHz to 3000 kHz is known as |
| A. | low frequency |
| B. | medium frequency |
| C. | high frequency |
| D. | very high frequency |
| Answer» B. medium frequency | |
| 69. |
Which of the following does not cause losses in optical fibre cables? |
| A. | stepped index operation |
| B. | impurities |
| C. | microbending |
| D. | attenuation in glass |
| Answer» A. stepped index operation | |
| 70. |
For a low level AM system, the amplifiers modulated stage must be |
| A. | linear devices |
| B. | harmonic devices |
| C. | class c amplifiers |
| D. | non-linear devices |
| Answer» A. linear devices | |
| 71. |
A telephone channel requires a bandwidth of about |
| A. | 1 khz |
| B. | 3 khz |
| C. | 10 khz |
| D. | 50 khz |
| Answer» B. 3 khz | |
| 72. |
For a given carrier wave, maximum undistorted power is transmitted when value of modulation is |
| A. | 1 |
| B. | 0.8 |
| C. | 0.5 |
| D. | 0 |
| Answer» A. 1 | |
| 73. |
As per Shannon-Hartley theorem, a noise less Gaussian channel has |
| A. | zero capacity |
| B. | infinite capacity |
| C. | small capacity |
| D. | none of the above |
| Answer» B. infinite capacity | |
| 74. |
DVD uses |
| A. | laser beam for both recording and playback |
| B. | laser beam for recording and video head for playback |
| C. | video head for recording and laser beam for playback |
| D. | none of the above |
| Answer» A. laser beam for both recording and playback | |
| 75. |
Fourier analysis indicate that a square wave can be represented as |
| A. | a fundamental sine wave and odd harmonics |
| B. | a fundamental sine wave and even harmonics |
| C. | a fundamental sine wave and harmonics |
| D. | fundamental and subharmonic sine waves |
| Answer» A. a fundamental sine wave and odd harmonics | |
