G.H.RaisoniCollege of Engineering, Nagpur
Department of Electronics Engineering
UHF & Microwave
UNIT -I
Objective questions
- What is microwave?
- What is the frequency range of microwave?
- What is the frequency range of UHF?
- Give the applications of microwave.
- What is a waveguide?
- Where the waveguide is used?
- What are the types of waveguide?
- Name the microwave tubes.
- What is Klystron?
- How much power gain is possible with two-cavity klystron amplifier?
- What is reflex klystron?
- Give its applications.
- How can klystron amplifier be converted into an oscillator?
- What is Transit time?
- What is the problem with transit time in diode?
- What do you understand by Transit time in Triode?
- Give application of two cavity kystron?
- What do mean by Bunching cavity?
- What do you understand by catcher cavity?
- What is bunching parameter?
Subjective questions
- What can be done to improve power gain?
- How you convert a klystron amplifier into an oscillator? What is velocity modulation?
- Explain the principle of operation of two-cavity klystron?
- What is bunching process?
- Explain the principle of operation of multicavity klystron?
- What is the plasma frequency?
- Explain the principle of operation of reflex klystron?
- What is the power o/p of Two-cavity klystron?
- Derive the efficiency of two-cavity klystron?
- What is the power o/p of Reflex klystron?
- Derive the efficiency of Reflex klystron?
- Give difference between Two cavity klystron and Reflex klystron?
- Explain Electronic admittance spiral?
- Derive relationship between Beam voltage and reflector voltage?
- Explain characteristics of Reflex Kystron.
UNIT -II
Objective questions
- Mention applications of TWT?
- What is BWO?
- On which principle does a BWO operate?
- Give applications of BWO.
- Is magnetron able to provide oscillations of very high peak power?
- State the types of magnetron?
- What is mode jumping in magnetrons?
- What is strapping?
- Where do you apply magnetron?
- How do you distinguish between TWT and klystron?
- What is Inverted co-axial magnetron?
- What are different types of strapping?
- What is the drawback of strapping?
- How this drawback of strapping can be overcome?
- What is the shot coming of negative resistance of magnetron?
- What is Cyclotron frequency magnetron?
- What is plasma frequency?
Subjective questions
- Explain the working principle of helix TWT?
- Explain different slow wave structures?
- What are the advantages of split anode magnetron?
- Explain the working principle of cylindrical magnetron?
- Explain the power o/p of cylindrical magnetron?
- Explain the efficiency of cylindrical magnetron?
- Explain the working principle of linear magnetron?
- Explain are the types of magnetron oscillators?
- Which tube is a wide band amplifier and Explain?
- Which diode is used as a microwave switch & what are the types of magnetron oscillators?
- Which tube is a wide band amplifier and Why?
- Which diode is used as a microwave switch and Why?
- Which cathode material is used in magnetron and Why?
- What are different types of strapping in cavity magnetron?
- Which cathode material is used in magnetron?
- What is the use of strapping in cavity magnetron?
- Which mode in a coaxial line has no cut off wavelength?
- What are O type tubes?
- What are M type tubes?
- State & explain the principle of operation of negative resistance type magnetron?
- State & explain the principle of operation of cyclotron frequency magnetron?
- State & explain the principle of operation of cavity magnetron
UNIT -III
Objective questions
- Name any two properties of scattering matrix.
- What are the transmitting coefficients?
- What are the reflection coefficients?
- How do you form H-plane Tee?
- What is the advantage of Magic Tee?
- What is rat race junction?
- Define coupling factor of DC.
- Define directivity of DC?
- Define isolation of DC?
- Name any two DC?
- What are ferrites?
- What is Faraday rotation?
- Name the microwave devices that make use of Faraday rotation?
- What is Scattering matrix?
Subjective questions
- Differentiate between transmission line and wave-guide?
- Which tee is called as shunt tee and why?
- Which tee is called as series tee and why?
- Differentiate between circulator and isolator?
- Which medium is best for handling large microwave power and why?
- Which mode in a coaxial line has no cut off wavelength and Why?
- Differentiate between transmission line and wave-guide?
- Which tee is called as shunt tee and why?
- Which tee is called as series tee and why?
- Differentiate between circulator and isolator?
- What is directional coupler DC?
- Explain is gyrator?
- Explain is isolator?
- Explain is circulator?
- What is fixed attenuator?
- What is variable attenuator?
UNIT -IV
Objective questions
- What is gyrator?
- What is isolator?
- What is circulator?
- Name two applications of circulator?
- What is the difference between microwave filters and low frequency filters?
- What are the factors that affect the microwave filter characteristics?
- What are the ways to obtain phase shifts in waveguide?
- What is the function microwave attenuator?
- Give common use of attenuator?
- State types of attenuator?
- Which attenuator do you use in rectangular waveguide?
- Which attenuator do you use in circular waveguide?
Subjective questions
- Which medium is best for handling large microwave power?
- What do you understand by the term microwave junction?
- What is the significance of S-matrix?
- What do you meant by T-junction?
- Explain the types of T-junction?
- Why do we call it H-plane Tee derive matrix?
- What is the reason to treat H plane Tee as Current junction?
- How do you form E-plane Tee derive matrix?
- Why do we call it E plane Tee derive matrix?
- How you use magic Tee for measuring impendence?
- How you use magic Tee as a duplexer?
- Derive the scattering matrix of rat race junction?
UNIT - V
Objective questions
- Which is the dominant mode in rectangular waveguides?
- Name the parameters that can be measured at microwave frequencies?
- What is VSWR?
- What is the relation between VSWR and reflection coefficient?
- What is slotted line?
- What are the types of bolometer?
- Compare between barraters and thermistor?
- What is the limitation of thermistor and barrater?
- How can it be overcome?
- Specify range for low power measurement?
- Specify range for high power measurement?
- What are types of calorimetric wattmeters?
- Name the two methods for measuring attenuation?
- State drawback of power ratio method?
- How can drawback of power ratio method be overcome?
- Define VSWR?
- What is double minimum method?
- State the three methods for measuring impedance?
- How do you distinguish between slotted line method and reflectometer method for measuring impedance?
Subjective questions
- For measurement of low power which technique do we use and How?
- For measurement of medium power which technique do we use and How?
- For measurement of high power which technique do we use and How?
- What is Calorimeter how we can use it as a power measurement device??
- Explain noise factor?
- How do you measure noise factor?
- List the methods for measuring Q of a cavity resonator and explain any one among them?
UNIT -VI
Objective questions
- List the reasons for not using conventional devices at frequencies >100MHz?
- What is parametric amplifier?
- Why is parametric amplifier called as low noise amplifier?
- Give the applications of parametric amplifier?
- What is degenerate parametric amplifier or oscillator?
- Give the applications of PIN diode?
- Differentiate between PIN diode and P-N junction diode?
- Can a PIN diode act as variable resistance?
- Can a PIN diode act as amplitude modulator?
- Can a PIN diode act as phase shifter?
- What are the modes of oscillation for Gunn effect oscillator?
- Give applications of gunn diode?
- Give the advantage of gunn diode over IMPATT diode?
- State disadvantage of gunn diode?
- Give types of planner transmission lines?
- What do you mean by strip lines?
- What do you understand by symmetrical strip lines?
- What is micro strip line?
- What are advantages of micro strip lines?
- State limitations of micro strip?
- What is characteristic impedance of micro strip?
- On what factors does the radiation loss of micro strip lines depend?
- Give the relation for Q of micro strip line.
- State the advantage of co-planner strip line over conventional parallel strip lines.
- Is it possible to design microwave components using strip lines?
- List the design consideration of micro strip line.
- List the advantages of microwave over low frequencies.
- Give the frequency range for HF band.
- Give the frequency range for VHF band.
- Give the frequency range for UHF band.
- Give the frequency range for L band.
- Give the frequency range for S band.
33. Give the frequency range for C band.
Subjective questions
- Differentiate between PIN diode and P-N junction diode?
- Derive efficiency of gunn diode?
- What is CW power gunn diode?
- What is pulsed power?
- How can gunn diode be used as an amplifier?
- List the performance characteristics of Gunn diode amplifier and explain?
- What does MASER stand for and why?
- What is MASER?
- List and explain two performance characteristics of MASER.
- Explain two applications of masers.
- What is difference between MASER and LASER?
- What is MASER?
- List and explain two performance characteristics of MASER.
- Explain two applications of masers.
- Explain disadvantages of MASER?
- What are planner transmission lines?
- Explain advantages of MASER?
- What are planner transmission lines?
- What do you mean by strip lines?
- What do you understand by symmetrical strip lines?
- What is micro strip line?
- What is a smith chart?
- What is stub matching?
- What is phase velocity?
- What is group velocity?
- Derive Give the equation for cut off frequency (fc).
- Derive the equation for phase shift constant (Bg).
- Derive the equation for cut off Wavelength.
- Derive relation between them?
30. What co you mean by the dominant mode?
31.Explain the characteristic impedance of micro strip lines?
32. Explain the different losses in micro strip lines?