MCQOPTIONS
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MCQOPTIONS
This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Antennas are bidirectional devices. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 2. |
Dipole antennas are an example for: |
| A. | wire antennas |
| B. | aperture antennas |
| C. | array antennas |
| D. | none of the mentioned |
| Answer» B. aperture antennas | |
| 3. |
An antenna has a field pattern E (θ) =cos θ. cos 2θ. The first null beam width of the antenna is: |
| A. | 450 |
| B. | 900 |
| C. | 1800 |
| D. | 1200 |
| Answer» C. 1800 | |
| 4. |
The beam width of the antenna pattern measured at half power points is called: |
| A. | half power beam width |
| B. | full null beam width |
| C. | beam width |
| D. | none of the mentioned |
| Answer» B. full null beam width | |
| 5. |
An antenna has a field pattern of E (θ) = cos2 θ, θ varies between 0 and 900. Half power beam width of the antenna is: |
| A. | 330 |
| B. | 660 |
| C. | 12000 |
| D. | none of the mentioned |
| Answer» C. 12000 | |
| 6. |
The number of patterns radiation pattern required to specify the characteristic are : |
| A. | three |
| B. | four |
| C. | two |
| D. | five |
| Answer» B. four | |
| 7. |
The basic equation of radiation that is applied to any antenna irrespective of the type of the antenna is: |
| A. | il= qv |
| B. | iq = lv |
| C. | i/l=q/v |
| D. | none of the mentioned |
| Answer» B. iq = lv | |
| 8. |
When the separation between two lines that carry the TEM wave approaches λ the wave tends to be radiated. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 9. |
                   is a device that converts electrons to photons or vice-versa. |
| A. | antenna |
| B. | electron gun |
| C. | photon amplifier |
| D. | microwave tube |
| Answer» B. electron gun | |
| 10. |
Reactive multipliers have a disadvantage that they cannot be used at very high frequencies and they become less efficient. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 11. |
For a resistive frequency multiplier of multiplication factor 2, the maximum theoretical conversion efficiency is: |
| A. | 50 % |
| B. | 25 % |
| C. | 75 % |
| D. | 12.5 % |
| Answer» C. 75 % | |
| 12. |
Resistive multipliers are more efficient as compared to reactive multipliers. |
| A. | true |
| B. | false |
| Answer» C. | |
| 13. |
In a diode frequency multiplier, an input signal of frequency fo applied to the diode is terminated with                   at all frequencies other than required harmonic. |
| A. | real impedances |
| B. | reactive impedance |
| C. | complex impedance |
| D. | none of the mentioned |
| Answer» C. complex impedance | |
| 14. |
If a frequency multiplier has a multiplication factor of 10, then the increase in noise level due to frequency multiplication is: |
| A. | 10 db |
| B. | 20 db |
| C. | 25 db |
| D. | 15 db |
| Answer» C. 25 db | |
| 15. |
A major disadvantage of frequency multipliers is that they multiply the noise factor along with frequency. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 16. |
Oscillators operating at millimeter wavelength are difficult to realize and are also less efficient. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 17. |
The major drawback of frequency multipliers is that they have: |
| A. | higher attenuation |
| B. | complex construction methods |
| C. | complex design |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |