MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 14 Mcqs, each offering curated multiple-choice questions to sharpen your Microwave Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
In a transistor amplifier, if the input impedance is -84-j1.9 Ω, then the terminating impedance required to create enough instability is: |
| A. | -84-j1.9 Ω |
| B. | 28+j1.9 Ω |
| C. | – (28+j1.9) Ω |
| D. | None of the mentioned |
| Answer» C. – (28+j1.9) Ω | |
| 2. |
If the input impedance of a diode used in the microwave oscillator is 45-j23 Ω, then the load impedance is to achieve stable oscillation is: |
| A. | 45-j23 Ω |
| B. | -45+j23 Ω |
| C. | 50 Ω |
| D. | 23-j45 Ω |
| Answer» C. 50 Ω | |
| 3. |
A one port oscillator uses a negative resistance diode having Гin=0.9575+j0.8034 (Z0=50Ω) at its desired frequency point. Then the input impedance of the diode is: |
| A. | -44+j123 |
| B. | 50+j100 |
| C. | -44+j145 |
| D. | None of the mentioned |
| Answer» B. 50+j100 | |
| 4. |
In a microwave oscillator, a load of 50+50j is connected across a negative resistance device of impedance -50-50j. Steady state oscillation is not achieved in the oscillator. |
| A. | True |
| B. | False |
| Answer» C. | |
| 5. |
IN_TRANSISTOR_OSCILLATORS,_FET_AND_BJT_ARE_USED._INSTABILITY_IS_ACHIEVED_BY:?$ |
| A. | Giving a negative feedback |
| B. | Giving a positive feedback |
| C. | Using a tank circuit |
| D. | None of the mentioned |
| Answer» C. Using a tank circuit | |
| 6. |
In a transistor amplifier, if the input impedance is -84-j1.9 Ω, then the terminating impedance required to create enough instability is:$# |
| A. | -84-j1.9 Ω |
| B. | 28+j1.9 Ω |
| C. | – (28+j1.9) Ω |
| D. | None of the mentioned |
| Answer» C. ‚Äö√Ñ√∂‚àö√ë‚àö¬® (28+j1.9) ‚âà√≠¬¨¬© | |
| 7. |
In transistor oscillators, the requirement of a negative resistance device is satisfied using a varactor diode? |
| A. | True |
| B. | False |
| Answer» C. | |
| 8. |
To achieve stable oscillation, Zin + ZL=0 is the only necessary and sufficient condition to be satisfied by the microwave oscillator. |
| A. | True |
| B. | False |
| Answer» C. | |
| 9. |
If the input impedance of a diode used in the microwave oscillator is 45-j23 Ω, then the load impedance is to achieve stable oscillation is:$ |
| A. | 45-j23 Ω |
| B. | -45+j23 Ω |
| C. | 50 Ω |
| D. | 23-j45 Ω |
| Answer» C. 50 ‚âà√≠¬¨¬© | |
| 10. |
A one port oscillator uses a negative resistance diode having Гin=0.9575+j0.8034 (Z0=50Ω) at its desired frequency point. Then the input impedance of the diode is:$ |
| A. | -44+j123 |
| B. | 50+j100 |
| C. | -44+j145 |
| D. | None of the mentioned |
| Answer» B. 50+j100 | |
| 11. |
For achieving steady state oscillation, the condition to be satisfied in terms of reflection coefficients is: |
| A. | –ì<sub>in</sub>=–ì<sub>L</sub> |
| B. | –ì<sub>in</sub>=-–ì<sub>L</sub> |
| C. | –ì<sub>in</sub>=1/–ì<sub>L</sub> |
| D. | None of the mentioned |
| Answer» D. None of the mentioned | |
| 12. |
In a microwave oscillator, a load of 50+50j is connected across a negative resistance device of impedance -50-50j. Steady state oscillation is not achieved in the oscillator. |
| A. | True |
| B. | False |
| Answer» C. | |
| 13. |
Any device with negative impedance as its characteristic property can be called: |
| A. | Energy source |
| B. | Energy sink |
| C. | Oscillator |
| D. | None of the mentioned |
| Answer» B. Energy sink | |
| 14. |
In microwave oscillators, negative resistance transistors and diodes are used in order to generate oscillations in the circuit. |
| A. | True |
| B. | False |
| Answer» B. False | |