previous year question papers for semester exam.

Nautical Electronics Paper – II (T 2305)
Date : 15.06.2015 Maximum Marks: 70
Time: 3 Hrs Pass Marks : 28
Note : Attempt any FIVE questions from the following. (5Γ—14=70 Marks)
All Questions carry equal marks.
1.(a)What do you mean by transistor biasing? What are the various methods used for transistor biasing. Explain base bias method in
detail. (7 Marks)
(b) In the transistor amplifier,𝑅𝑐=10π‘˜Ξ©, 𝑅𝐿=30π‘˜Ξ© and
𝑉𝐢𝐢=20𝑉.The values 𝑅1 and 𝑅2 are such so as to fix the
operating point at 10V, 1mA .Draw the d.c. and a.c. load lines.
Assume 𝑅𝐸 is negligible. (7 Marks)
2.(a) Explain the action of emitter follower with neat circuit diagram. (7 Marks)
(b) With a neat circuit diagram, explain the working of transformer –
coupled amplifier. (7 Marks)
3. (a) Show the circuit of complete CE amplifier. How will you draw the A.C.
and D.C. quivalent circuits of CE amplifier. Derive the equation for
voltage and current gains. (7Marks)
(b) In a transistor amplifier, when the signal changes by 0.02 V, the base current changes by 10 ΞΌA and collector current 1mA. If collector load 𝑅𝑐=5π‘˜Ξ© and 𝑅𝐿=10π‘˜Ξ©.find: current gain, input impedance,a.c. load, voltage gain and power gain. (7 Marks)
4. (a) i) Derive an expression for voltage gain of amplifier with negative voltage feedback amplifier (5 Marks)
ii) The overall gain of multistage amplifier is 140.When
negative voltage Feedback is applied, gain is reduced to 17.5.
Find the fraction of the output that is feedback to the input. (2 Marks)
(b) Explain piezoelectric crystals. The ac equivalent circuit of a crystal has
these values: L=1H, C=.001pF,R=1000 Ξ© and πΆπ‘š=20 pF.
Calculate 𝑓𝑠 π‘Žπ‘›π‘‘ 𝑓𝑝 of the crystal. (7 Marks)
5. (a) With a neat diagram, explain the action of RC phase shift oscillator. (7 Marks)
(b) Find the value of 𝐼𝑐 for potential divider method if 𝑅1=39π‘˜Ξ©, 𝑅2= 10π‘˜Ξ©,𝑉𝑐𝑐=9 𝑉,𝑅𝑒=1π‘˜Ξ©,𝑅𝑐=2.7π‘˜Ξ©,𝑉𝐡𝐸=0.15 𝑉 and Ξ²=90.
(7 Marks)
6. a) Explain the detailed block diagram of operational amplifier.(7 Marks)
b) Explain the circuit of Op-amp as an integrator. Derive the equation for
output voltage. If the input to the op-amp integrator is square wave.
What will be the nature of output. (7 Marks)
7.a) Explain the basic circuit of differential amplifier. State characteristics of
operational amplifier. (7 Marks)
b)Write short note on: (ANY TWO) (7 Marks)
i. Positive Feedback
ii. Frequency response of an amplifier
iii Power amplifier