Q. Consider the following statements:

1. Dissipative attenuator has a fixed value of attenuation.
2. Reflective attenuator has a fixed value of attenuation.
3. Both dissipative and reflective attenuators are available only with fixed attenuation.
4. Both dissipative and reflective attenuators are available with either fixed or variable attenuation.

Which of the above are correct?

View solution

Q. Impedance inversion may be obtained with

View solution

Q. Power gain of a multicavity klystron amplifier is

View solution

Q. The expression HZ = C cos(Bx) cos(Ay)yz is for

View solution

Q. Assertion (A): Impedance matching can be done by using stubs.

Reason (R): A double stub is used for impedance matching when frequency of signal varies.

View solution

Q. Read the following statements about TWT

1. It uses thermionic emission.
2. It uses an attenuater.
3. It is inherently a resonant device.
4. It has broad bandwidth.

Which of the above are correct?

View solution

Q. If a line having Z₀ = 300 ∠ 0 W is short circuited at far end, VSWR is

View solution

Q. A klystron amplifier generally uses Pierce gun

View solution

Q. If a short line is terminated in characteristic impedance it behaves as an infinite line.

View solution

Q. Ga As exhibits negative differential mobility

View solution

Q. Consider the following statements:

1. Bunching of electrons occurs in two cavity klystron amplifier.
2. Bunching of electrons occurs in multi cavity klystron amplifier.
3. Bunching of electrons occurs in reflex cavity klystron amplifier.

Which of the above statements are correct?

View solution

Q. Assertion (A): For high frequency lines inductive reactance is very high as compared to ac resistance.

Reason (R): Due to skin effect ac resistance of line is higher than dc resistance.

View solution

Q. Consider the following applications

1. Switch
2. Attenuator
3. Phase shifter
4. Oscillator

In which of the above can a PIN diode be used?

View solution

Q. Out of modes TE₂₀ and TE₃₀ of propagation of electromagnetic engery

View solution

Q. A TE₁₀ rectangular waveguide is to be designed for operation over 25-35 GHz and the band centre is 1.5 times the cutoff frequency. The dimension of broadside is

View solution

Q. In a klystron amplifier the force on all electrons

View solution

Q. If load impedance ZL >> Z0, then

View solution

Q. The inductance of a twin feeder used to connect antenna to TV receiver is about

View solution

Q. Assertion (A): Impatt diode is an avalanche diode.

Reason (R): Avalanche breakdown phenomenon occurs when a p-n junction is reverse biased.

View solution

Q. A radar has a maximum range of 120 km. The maximum allowable pulse repetition frequency for unambiguous reception is

View solution