B.E-B.E Electronics and Communication Engineering 1st Year BASIC ELECTRONICS ENGINEERING(University of Pune, Pune-2013)

UNIVERSITY OF PUNE
[4361]-12
F. E.(Common)Examination - 2013
BASIC ELECTRONICS ENGINEERING
(2008 Pattern)
[Total No. of Questions: 6] [Total No. of Printed Pages :3]

Time : 3 Hours                                                                                                  Max. Marks : 80

(1) Answer Q1 or Q2, Q3 or Q4, Q5 or Q6 .
(2) Answers all questions in same answer-book.
(3) Black figures to the right indicate full marks.
(4) Neat diagrams must be drawn wherever necessary.
(5) Use of electronics pocket calculator is allowed.
(6) Assume suitable data, if necessary.

Q1 a) A bridge rectifier is applied with input from a step down transformer [8]
having turns ratio 8:1 and input 230V, 50Hz. If Rf =1Ω, Rs =10 Ω and
RI =2 KΩ. Find: I. DC power output II. PIV across each diode
III. Percentage efficiencyIV. Percentage regulation at full load.
b) Explain how transistor can be used as an amplifier with the help of [6]
load line approach.
c) State the various methods of turning on SCR. [4]
OR
Q2 a) With the help of neat circuit diagram, explain how will you use the [8]
Zener diode as a voltage regulator. What is maximum and minimum limit
for the load current?
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b) Sketch JFET drain and transfer characteristics and indicate following [6]
parameters: I. Pinch off voltage II. Drain self saturating current
III. VGS(OFF) IV. Region of operation
c) Draw and explain V-I characteristics of Triac. [4]
Q3 a) Draw a neat diagram of three-input inverting summing amplifier using [8]
op-amp and obtain the expression of its output voltage.
b) Realize three-input gate using two-input gates for the following gate: [8]
I. AND II. OR III. NAND IV. NOR
OR
Q4 a) A sinusoidal signal with peak value 6mV with 2kHz frequency is [8]
applied to the input of ideal op-amp integrator with R1 =100 kΩ and
Cf=1 μ F.
Find the output voltage.
b) Prove the following using DeMorgan’s theorem. [8]
1) AB+CD= ( ̄A ̄B) . ( ̄C ̄D)
2) (A+B)(C+D)= ( ̄A ̄B)+( ̄C+ ̄D)
Q5 a) Explain the following characteristics of transducer: [4]
I. Accuracy II.Ruggedness III.Linearity IV.Repeatability
b) Explain the principal of operation of Stain Gauge. [4]
c) Explain Super-heterodyne receiver with the help of block diagram. [8]
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OR
Q6 a) What is RTD? Draw its constructional diagram and explain its [8]
operation.
b) Explain wired communication and wireless communication. [4]
c) Explain problem with pair cables. State different types of twisted [4]
pair cable.
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