microwave engineering objective questions and answers part1

Q1. Easily adjustable tuning component in a waveguide is
(A) plunger
(B) plunger and stub
(C) screw
(D) both (a) and (c)

Q2. A Klystron is a cavity acting as buncher and catcher is used as microwave tube for
(A) Guiding waves
(B) Velocity modulation
(C) Frequency modulation
(D) impedance matching

Q3. Which of the following sinusoidal oscillator is preferred for microwave frequencies?
(A) resonant circuit oscillator
(B) RC phase shift oscillators
(C) negative resistance oscillators
(D) all of the above

Q4. The negative resistance in Gunn diode is due to
(A) electron transfer to a less mobile energy level
(B) high reverse bias
(C) electron domain formation at the junction
(D) tunneling across the junction

Q5. TWT is basically
(A) an oscillator
(B) tuned amplifier
(C) wideband amplifier
(D) an audio amplifier

Q6. An attenuator is used with TWT to
(A) prevent oscillations
(B) increase gain
(C) prevent saturation
(D) help bunching

Q7. For handling large microwave power, the best medium is
(A) coaxial line
(B) rectangular waveguide
(C) stripline
(D) circular wave guide

Q8. Due to curvature of earth, microwave repeaters are placed at distance of about
(A) l0 Km
(B) 50 Km
(C) 200 Km
(D) 500 Km

Q9. The Biggest Disadvantage the IMPATT Diode has is its
(A) Low Efficiency
(B) High Noise
(C) Low BW
(D) Inutility to provide Pulse Operation

Q10. Vacuum Tube Eventually Fall at Microwave Frequencies Because of their
(A) Inter Electrode Capacitance
(B) Small Series inductance
(C) Large Shunt Capacitance
(D) Short Transit Time

Q11. TWT uses a helix
(A) To reduce the axial velocity of RF field
(B) To increase the efficiency
(C) To reduce the noise
(D) To ensure broad band operation

Q12. A waveguide acts as a
(A) Low pass filter
(B) Band pass filter
(C) High pass filter
(D) All of the above

Q13. The MASER occurs in the portion of electromagnetic spectrum is
(A) Infrared
(B) UV
(C) Visible
(D) RF

Q14. Which of the following diodes has a p-n-i-p structure?
(A) TRAPATT
(B) IMPATT
(C) BARITT
(D) Gun diode

Q15. A laser may be internally modulated at a frequency equal to the frequency separation between axial modes. This phenomenon is termed as
(A) mode locking
(B) pad locking
(C) locking
(D) none of the above

Q16. A reflex Klystron is a
(A) Microwave oscillator
(B) Microwave amplifier
(C) Both as Microwave amplifier and oscillator
(D) A high gain cavity

Q17. Ionospheric propagation is not possible for microwaves because
(A) Microwaves will be fully absorbed by the ionospheric layers
(B) There will be an abrupt scattering in all directions
(C) Microwave will penetrate through the ionospheric layers
(D) There will be dispersion of microwave energy

Q18. HEMT used in microwave circuit is a
(A) Source
(B) High power amplifier
(C) Detector
(D) Low noise Amplifier

Q19. Most of the power measuring microwave devices measure
(A) Average power
(B) Peak power
(C) Instantaneous power
(D) None of these

Q20. A disadvantage of microstrips with respect to stripline circuit is that the former:
(A) Do not let themselves to be printed-circuits
(B) Are more likely to radiate
(C) Are bulkier
(D) Are more expensive and complex to manufacture