1. The value of-C which gives the critical damping in the given circuit is

<img src='./qimages/1642-1.jpg'>

2F

4F

8F

1F

2. A series RLC circuit resonates at 3 MHz and has 3-dB bandwidth kHz. The Q of the circuit at resonance

30

300/root2

300

300 root2

3. The value of resistance R shown in the given figure is

<img src='./qimages/1642-3.jpg'>


3.5 ohm

2.5 ohm

1 ohm

4.5 ohm

4. At 3-dB frequencies, current in the series RLC circuit equal current at resonance multiplied by


1/2

1/root2

1/4

1/2 root 2

5. A series RLC circuit resonates at 1000kHz. At frequency of 995kHz, the circuit impedance is

Resistive

minimum

Inductive

capacitive

6. If each stage had gain of 10dB and noise figure of 10dB, then the overall noise figure of two-stage cascade amplifier will be

10

1.09

1.0

10.9

7. In Sigma delta ADC, high bit accuracy is achieved by

Over sampling and noise shaping

Over sampling

Under sampling

None of the above

8. Let denote the delta function. The value of the integral <img src='./qimages/1642-8.jpg'> is

1



0

pie/2


9. Consider the compound system shown in the above figure.its-output is equal to the-input with a delay of two units. If the transfer function of the first system is given by Z-0.5/Z-0.8,then the <img src='./qimages/1642-9.jpg'>


<img src='./qimages/1642-9a.jpg'>

<img src='./qimages/1642-9a.jpg'>

<img src='./qimages/1642-9a.jpg'>

<img src='./qimages/1642-9a.jpg'>


10. The z-transform of the signal

<img src='./qimages/1642-10.jpg'>

<img src='./qimages/1642-10a.jpg'>


11. For the circuit shown in the given figure, the voltage VAB is

<img src='./qimages/1642-11.jpg'>

6V

10V

25V

40V

12. The equivalent capacitance across will be

<img src='./qimages/1642-12.jpg'>

0.2mewF

0.1mewF

0.5mewF

0


13. The transfer function, is that of a


Low-pass filter

Notch filter

High-pass filter

Band-pass filter


14. A particular current is made up of two components:a 10A dc and a sinusoidal current of peak value of 1.414 A. The average value of the resultant current is

Zero

24.14A

10A

14.14A


15. By doubling the sampling frequency

Quantisation noise decreases by 3dB

Quantisation noise density decreases by 3dB

Quantisation noise increases by 3dB

Quantisation noise density increases by 3dB


16. The output voltage of the circuit shown in the given figure is
<img src='./qimages/1642-16.jpg'>


Zero

5.7V

6.9V

12.6V

17. Assuming that only the X and Y logic inputs are available and their complements X and Y are not avaUable, what is the minimum number of two-input NAND gates requires to implement X

a)2

b)3

c)4

d)5

18. In the given network of AND and OR gates f can be written as: <img src='./qimages/1642-18.jpg'>

<img src='./qimages/1642-18a.jpg'>

19. A Pulse train with a frequency of 1MHz is counted using a modulo 1024 ripple-counter built with J-K flip-flops. For proper operation of the counter the maximum permissible propagation delay per flip-flop stage is

100 n sec

50 n sec

20 n sec

10 n sec

20. The A/D converter used in a digital voltmeter could be successive approximation type Flash converter type Dual slope converter type. The correct sequence in the increasing order of their conversion times is











21. The resolution of a D/A converter is approximately 0.4% of its-full-scale range. It is

An 8-bit converter

A 10-bit converter

A 12 bit converter

A 16 bit converter

22. In a microprocessor, the resister which holds the address of the next instruction to be fetched is

Accumulator

Program counter

Stack pointer

Instructor register

23. In microcomputer, WAIT states are used to

Make the processor wait during a DMA operation

Make the processor wait during a power interrupt processing

Make the processor wait during a power shutdown

Interface slow peripherals to the processor

24. Which of the following statements are correct 1)A flip-flop is used to store 1 bit of information 2)Race-around condition occurs in a J-K flip-flop when both the inputs are 1 3)Master-slave configuration is used in flip-flops to store 2 bits of information 4)A transparent latch consists of a D-type flip-flop

1,2and3

1,3and4

1,2and4

2,3and4


25. How many 1 are present in the binary representation of 3x512+7x64+5x8+3?

8

9

10

11

26. For emitter-coupled logic, the switching speed is very high because

Negative logic, is used

The transistors are not saturated when conducting

Emitter-coupled transistors are used

Multi-emitter transistors are used


27. The out put of the circuit shown below is <img src='./qimages/1642-27.jpg'>


A pulse train of duration 0.5 sec.

A pulse train of duration 2 sec.

A pulse train of duration 1 sec.

A pulse train of duration 5 sec.


28. Gray code for number 7 is

1100

1001

0110

0100

29. 10 bit AJD converters, the quantization error is given by (in percent)


1

2

0.1

02

30. For the switch-circuit,taking open as 0 and closed as the expression for the circuit is Y. <img src='./qimages/1642-30.jpg'>



A+BC+D



None of these

31. The Boolean expression for the shaded area in the Venn diagram is <img src='./qimages/1642-31.jpg'>


x bar+Y bar+Z

X Y bar Z bar YZ



XY barZ+XY

32. If the memory chip size is 256*1 bits, then the number of chips required to make up 1K bytes of memory is

32

24

12

8

33. Given the decimal number an eight bit two's complement representation is given by

11101110

11101101

11101100

None of these


34. The function shown in the figure when simplified will yield a result with <img src='./qimages/1642-34.jpg'>


2 terms

4 terms

7 terms

16 terms


35. The logic circuit given below converts a binary code Y1Y2Y3 into

Excess-3 code

Gray code

BCD code

Hamming code

36. A 4-bit synchronous counter uses flip-flops with propagation delay time of 25ns each. The maximum possible time required for change of state will be

a)25ns

b)50ns

c)75ns

d)100ns

37. An electromagnetic wave incident on a perfect conductor is

Entirely reflected

Fully transmitted

Partially transmitted

None of these

38. The characteristic impedance of a lossless transmission line is given by

Z=root LC

Z=root C/L

Z=LC

Z=root L/C

39. A lossless line of 50 ohms is terminated in a load of 100 ohms resistive. The VSWR is

1:2

2:1

4:1

1:4

40. Which of the following does not exist in wave guides

TE waves

TM waves

TE waves and TM waves

TEM waves

41. Two carriers of 2GHz and 4GHz respectively are frequency modulated by a signal of 10KHz,such that bandwidth of the FM signal in the two cases are same. The peak deviation in the two cases are in the ratio of

1:8

1:2

2:1

1:1

42. The bandwidth required for QPSK modulated channel is

Twice the BW of BPSK

Equal to BPSK

Equal to FSK

Half of the BW of BPSK

43. Magic T is

Four part junction

Two part junction

Three part junction

It is not junction


44. Diplexer is made of

Only receive filter

Only transmit filter

Only circulator filter

Both receive filter and transmit filter

45. The gain G of an antenna of effective area A is given by


G=4pie lamda/A2

G=4pieA/lamda

G=4pieA/lamda2

None

46. If the short circuit and open circuit impedance of a line are 5 and 20 ohm respectively the characteristic impedance is given by


100 ohm

10 ohm

15 ohm

10000 ohm


47. The input impedance of short circuited line of length l where lamda/4 l lamda/2, is


Capacitive

Inductive

Resistive

None of these


48. Maximum coding gain in

Block Codes

Convolution Codes

Turbo Codes

RS Codes

49. Noise figure of an amplifier depends on


Bandwidth

Output power

Power input

None of the above


50. BCH code belongs to

Block Codes

Convolution Codes

Turbo Codes

None of the above

51. When a carrier is phase modulated, with an integrated modulating signal, the resultant is

Phase modulated signal

Frequency modulated signal

Amplitude modulated signal

QPSK modulated signal

52. A satellite orbiting in 600km orbit transmits 5GHz frequency. The Doppler shift observed at the ground station, when the satellite. is over head of the station is

Zero

Maximum

Infinity above

None of the

53. A communication channel disturbed by additive white Gaussian noise has a bandwidth of 4kHz and SNR of 15. The highest transmission rate that such a channel can support (in k-bits/sec) is

16

1.6

3.2

60

54. A dual directional coupler connected in a microwave reflectometer measurement setup.The reading of the power meter in the forward direction is 100mw and in the reverse direction 4 mw. The VSWR is

4

0.4

1.5

10

55. Linear amplifier with a gain of 30dB is fed with 1.0mewW power, the output power of the amplifier

1.0W

0 dBm

30dBm

-30dBm

56. 10Watts RF power is transmitted with a circular polarized antenna having gain of 10dB. A receiving antenna has vertical polarization. The path loss is 100dB. The receiving signal is

-83dBW

-80dBW

-86dBW

+80dBW

57. P bar Q bar and R bar are in equilibrium,if R bar is

2k

i +2k

i j +2k

i -2k

58. A rigid body is rotating with constant angular velocity w about a fixed axis, if v is the velocity of a point of the body, then curl v

w

w2

2w

2w2

59. laplace transform of sin3 2t is


<img src='./qimages/1642-59a.jpg'>

<img src='./qimages/1642-59b.jpg'>

<img src='./qimages/1642-59c.jpg'>

<img src='./qimages/1642-59d.jpg'>


60. The value of the determinant <img src='./qimages/1642-60.jpg'> is

0



1

2

61. Solution of (D2 4)y sin2 is


<img src='./qimages/1642-61a.jpg'>

<img src='./qimages/1642-61b.jpg'>

<img src='./qimages/1642-61c.jpg'>

<img src='./qimages/1642-61d.jpg'>


62. The value of k for which the lines 2x 3y and 3x ky are concurrent is



3

2




63. A box cOl1tClin$ 5 black and 5 red balls. Two balls are randomly picked one after another from the box, without replacement. The probability for both balls being red is

1/90

1/5

19/90

2/9

64. x3+xsinx is

Constant function

Odd function

Even function

Periodic function


65. <img src='./qimages/1642-65.jpg'>


<img src='./qimages/1642-65a.jpg'>

<img src='./qimages/1642-65b.jpg'>

<img src='./qimages/1642-65c.jpg'>

<img src='./qimages/1642-65d.jpg'>


66. Eigen values of <img src='./qimages/1642-66.jpg'>







6,1

67. The approximate equivalent resistance at the points X1 and X2 in the circuit shown below
<img src='./qimages/1642-67.jpg'>


60 ohm

40 ohm

80 ohm

20 ohm

68. An inductor supplied with 50V ac with a frequency of 10kHz passes a current of 7.96 mA. The value of inductor is

1mH

10mH

100mH

1H

69. In a capacitor, the electric charge is stored in

Dielectric

Metal plates

Dielectric as well as metal plates

Neither dielectric nor metal plates

70. Oscillator requires

No feedback

Negative feedback

Positive feedback

Either positive or negative feedback

71. Which loss in a transformer varies significantly with load?

Hysteresis loss

Eddy current loss

Copper loss

Core loss


72. The resistance of a parallel circuit consisting of two resistors is 12 ohm. One of the resistance wires breaks and the effective resistance becomes 18 ohm. The resistance of the broken wire is

48 ohm

18 ohm

36 ohm

24 ohm

73. Time constant of a series R-L circuit equals

L/R second

LR second

L2 R

Zero

74. A dc voltage V is applied at time t=0 to a series RC circuit The steady state current is

V/R

V/C

V/root R2+C2

Zero


75. The given circuit represents a <img src='./qimages/1642-75.jpg'>

Low pass filter

High pass filter

Band pass

Band stop filter filter

76. The very low frequency gain of the low pass filter shown in the given figure is <img src='./qimages/1642-76.jpg'>


10dB

20dB

30dB

40dB



77. The time-constant of the network shown in the figure is
<img src='./qimages/1642-77.jpg'>

CR

2CR

CR/4

CR/2


78. For the circuit shown below the current I flowing through the circuit will be
<img src='./qimages/1642-78.jpg'>

1/2A

1A

2A

4A

79. When L is doubled and C is halved, the resonance frequency of series tuned circuit becomes

Doubled

Halved

One quarter

Unchanged

80. In a Series resonant circuit, with the increase in L

Resonant frequency will decrease

Bandwidth will decrease

Q will increase

All of these