Basic Electronics Engineering (BXE) - Dec 2014

First Year Engineering (Semester 2)

TOTAL MARKS: 50
TOTAL TIME: 2 HOURS (1) Solve Q.1 or Q.2, Q.3 or Q.4, Q.5 or Q.6, Q.7 or Q.8
(2) Assume suitable data, if necessary.

Answer any one question from Q1 and Q2

1 (a) Compare performance of half wave rectifier and full wave rectifier with respect to following parameters:
1) I_DC
2) I_RMS
3) Rectifier efficiency
4) Ripple factor
5) PIV
6) TUF(6 marks) 1 (b) Explain how transistor can be used as an amplifier with the help of D.C. load line approach.(6 marks) 2 (a) Explain the operation of n-channel enhancement type MOSFET with its characteristics.(6 marks) 2 (b) Determine the O/P waveform for the circuit shown in fig. (6 marks)

Answer any one question from Q3 and Q4

3 (a) Explain the working of inverting summing amplifier with two inputs along with its wave foRMS.(6 marks) 3 (b) State and prove the de Morgan's theorem. Simplify the following Boolean expression: AB+AB(6 marks) 4 (a) With the help of block diagram of IC555 explain its operation in Astable mode.(6 marks) 4 (b) Compare Microprocessor and micro-controller.(6 marks)

Answer any one question from Q5 and Q6

5 (a) Explain the operation of SCR with the help of V-I characteristics.(7 marks) 5 (b) Explain the selection criteria of a Transducer.(6 marks) 6 (a) Define 'Dark current'. Draw and explain the characteristics of photo transistor.(6 marks) 6 (b) Explain the construction of DIAC and draw its characteristics.(7 marks)

Answer any one question from Q7 and Q8

7 (a) Draw and explain the electromagnetic or IEEE frequency spectrum.(7 marks) 7 (b) Compare AM and FM.(6 marks) 8 (a) Draw and explain the block diagram of GSM.(7 marks) 8 (b) A carrier of 10 V peak and frequency 100 KHz is amplitude modulated by a sine wave of 4 V peak and frequency 1000 Hz. Determine the modulation index for the modulated wave and draw the frequency spectrum for AM wave.(6 marks)