STUPIDSID
1 (a)
State and explain Lorentz Reciprocity theorem.
5 M
1 (b)
Enumerate and explain the advantage and application of Microwaves.
5 M
1 (c)
Differentiate between Waveguide and Transmission Lines.
5 M
1 (d)
A 50Ω transmission line is matched to a 10V source that feeds a load ZL=100Ω. If the line is 2.3λ long and has an attenuation constant α=0.5dB/λ. Find the power that are delivered by the source lost in the line and delivered to the load.
5 M
2 (a)
Explain the working and derive S matrix for a two hole directional coupler.
10 M
2 (b)
Derive the expression for velocity modulation process for two cavity klystrons.
10 M
3 (a)
Derive expression for phase velocity, cut off frequency, cut off wavelength and field equation for circular waveguide.
10 M
3 (b)
A lossless line of characteristic impedance R0=50 Ω is to be matched to a load ZL=50[2+j(2+√3)]Ω by means of a lossless short-circuited stub. The characteristic impedance of the stub is 100 Ω. Find the stub position and length so that a match is obtained.
10 M
4 (a)
Explain the working of a negative resistance Parametric amplifier and explain its application .
10 M
4 (b)
An n GeP Ga Asn GaAs heterojunction transistor at 300oK has the following Parameter ?
Donor density in n Ge region: Nd=5x1018 cm-3
Acceptor density in P GaAs region: Na=6x1016 cm-3
Hole life time: τp=6x10-6 sec
Bias voltage at emitter junction: VE=1
Cross section: A=2x10-2 cm-2
Compute :-
(i) The built in voltage in the P GaAs side
(ii) The hole mobility
(iii) The hole diffusion constant
(iv) The minority hole density in the nGe region
(v) The minority electron density in the P GaAs region
(vi) The diffusion length
(vii) The emitter junction current
Donor density in n Ge region: Nd=5x1018 cm-3
Acceptor density in P GaAs region: Na=6x1016 cm-3
Hole life time: τp=6x10-6 sec
Bias voltage at emitter junction: VE=1
Cross section: A=2x10-2 cm-2
Compute :-
(i) The built in voltage in the P GaAs side
(ii) The hole mobility
(iii) The hole diffusion constant
(iv) The minority hole density in the nGe region
(v) The minority electron density in the P GaAs region
(vi) The diffusion length
(vii) The emitter junction current
10 M
5 (a)
A reflection klystron operates under following condition:VO=600V, L=1mm, Rsh=15KΩ,e/m=1.759x1011, fr=9GHz.
The tube is oscillating at fr at the peak of the n=2 mode or 1(3/4) mode.Assume that the transit time through the gap and beam loading can be neglected.
(i) Find the value of repeller voltage Vr
(ii) Find the direct current necessary to give a Microwave gap voltage of 200V
(iii) What is electric efficiency under this condition.
The tube is oscillating at fr at the peak of the n=2 mode or 1(3/4) mode.Assume that the transit time through the gap and beam loading can be neglected.
(i) Find the value of repeller voltage Vr
(ii) Find the direct current necessary to give a Microwave gap voltage of 200V
(iii) What is electric efficiency under this condition.
10 M
5 (b)
Explain different mode of Gunn diodes .
6 M
5 (c)
Explain measurement of dielectric constant .
6 M
6 (a)
Design a composite low pass filter by image parameter method with following specification-
RO=50 Ω, fc=50MHz, f∞=52MHz
RO=50 Ω, fc=50MHz, f∞=52MHz
10 M
6 (c)
Compare advantage and disadvantage of a GaAs MOSFET with Si MOSFET
4 M
6(b)
What are different limitation of conventional tube .
6 M
Write short notes on:
7 (a)
Microwave filters .
5 M
7 (b)
Magic tee .
5 M
7 (c)
TWT .
5 M
7 (d)
Show that TM01 and TM10 modes in a rectangular waveguide do not exist.
5 M
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