Electronics And Telecomm (Semester 3)
Total marks: 80
Total time: 3 Hours
INSTRUCTIONS
(1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Draw neat diagrams wherever necessary.
1.a.
Draw equivalent circuit for give magnetically coupled circuit.
(5 marks)
00
1.b.
In the network if Fig. switch is closed at t = 0. With capacitor uncharged, find value for i and $\frac{d i}{d t}$ at $t=0^{+}$
(5 marks)
00
1.c.
Prove that AD − BC = 1 for Transmission parameters.
(5 marks)
00
1.d.
Design an m-derived T section high pass filter with a cut-off frequency of 2kHz. Design impedance of 700Ω and m = 0.6.
(5 marks)
00
2.a.
In the network shown in Fig., at t = 0, switch is opened. Calculate v, $\frac{\mathrm{d} \mathrm{v}}{\mathrm{dt}}, \frac{\mathrm{d} 2 \mathrm{v}}{\mathrm{d} \mathrm{t} 2}$ at t = 0+.
(10 marks)
00
2.b.
For the network shown in Fig., find Y and Z-parameters.
(10 marks)
00
3.a
Determine the current through 10Ω resistor in the network of Fig.
(10 marks)
00
3.b.
The parameters of a transmission lines are R = 65Ω/km, L=1.6mH/km, G = 2.25 mmho/km, C=0.1μF/km. Find
i. Characteristic Impedence
ii. Propagation Constant
iii. Attenuation Constant
iv. Phase Constant at 1 kHz
(10 marks)
00
4.a.
Determine whether following functions are positive real
i) $\frac{s^{2}+2 s+4}{(s+1)(s+3)}$
ii) $\frac{s^{2}+25 s+25}{s+4}$
(10 marks)
00
4.b.
Find Norton's equivalent network.
(10 marks)
00
5.a.
Find Y-parameters for the network shown in Fig.
(10 marks)
00
5.b.
Realize the following functions in Foster II and Cauer I form
$Z(s)=\frac{2\left(s^{2}+1\right)\left(s^{2}+9\right)}{s\left(s^{2}+4\right)}$
(10 marks)
00
6.a.
A transmission line has a characteristics impedance of 50 ohm and terminate in a load $Z_{L}=25+j 50$ ohm description Use smith chart and Find VSWR and Reflection coefficient at the load.
(10 marks)
00
6.b.
Determine current i2 (t) in the network of Fig., when switch is closed at t = 0. The inductor is initially deenergized.
(10 marks)
00