bn Mishra

BSNL J.T.O. Recruitment Exam 2001

Paper-I

1. A second-order system has a transfer function given by  If the system, initially at rest is subjected to a unit step input at t = 0, the second peak in the response will occur at

(A)  π sec

(B)  π/3 sec

(C)  π/2 sec

(D)  2π/3 sec

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2. The open-loop transfer function of a feedback control system is  The gain margin of the system is

(A)  2

(B)  8

(C)  4

(D)  16

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3. A silicon sample is uniformly doped with 10¹⁶ phosphrous atoms/cm³ and 2 × 10¹⁶ boron atoms/cm³. If all the dopants are full ionized, the material is

(A)  p-type with carrier concentration of 2 × 10¹⁶/cm³

(B)  p-type with carrier concentration of 10¹⁶/cm³

(C)  n-type with carrier concentration of 10¹⁶/cm³

(D)  T₂-will get damaged and T₁ will be safe.

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4. The initial contents of the 4-bit serial-in-parallel-out, right-shift, Shift Register shown in fig. is 0110. After 3 clock pulses are applied, the contents of the Shift Register will be

(A)  1 1 1 1

(B)  0 1 0 1

(C)  1 0 1 0

(D)  0 0 0 0

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5. shows the circuit of a gate in the Resistor Transistor Logic (RTL) family. The circuit represents a

(A)  NAND

(B)  OR

(C)  NOR

(D)  AND

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6. The logic realized by the circuit shown in Fig. is 

(A)  F = B . C

(B)  F = A ⊕ C

(C)  F = A . C

(D)  F = B + C

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7. In a multicavity magnetron, strapping is employed primarily

(A)  to prevent mode jumping

(B)  to increase the output of the magnetron

(C)  to reduce the back heating of the cathode

(D)  to increase the separation between the resonant frequencies in the π-mode and in the adjacent modes

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8. A Lissajous pattern, as shown in Fig. is observed on the screen of a CRO when voltages of frequencies f_x and f_y are applied to the x and y plates respectively. f_x : f_y is then equal to

(A)  3 : 2

(B)  1 : 2

(C)  2 : 1

(D)  2 : 3

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9. In the transistor circuit shown in Fig. collector-to-ground voltage is +20 V. Which of the following is the probable cause of error?

(A)  Emitter to ground connection open

(B)  Collector-emitter terminals shorted

(C)  10kΩ resistor open

(D)  Collector-base terminals shorted

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10. Part of the digital phase meter is shown in the fig. If the input signals are V_B(t) = V_R sin ωt and V_P(t) = V_P sin(ωt + 30°) the reading of the meter will be

(A)  210°

(B)  330°

(C)  150°

(D)  30°

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11. The response of an initially relaxed linear constant parameter network to a unit impulse applied at t = 0 is 4 e^−2tu(t). The response at this network to a unit step Function will be:

(A)  (1 – 4e^−4t)u(t)

(B)  4[e^−t – e^−2t] u(t)

(C)  sin 2t

(D)  2[1 – e^−2tu(t)]

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12. The open circuit  impedance matrix of the 2-port network shown in Fig. is

(A)   

(B)   

(C)   

(D)   

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13. The impulse response and the excitation function of a linear time invariant causal system are shown in Fig. (i) and (ii) respectively. The output of the system at t = 2 sec is equal to

.

(A)  0

(B)  3/2

(C)  1/2

(D)  2

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14. An electromechanical closed-loop control system has the following characteristic equation

s³ + 6Ks² + (K + 2) s + 8 = 0

where K is the forward gain of the system.

The condition for closed loop stability is

(A)  K = −0.528

(B)  K = 2

(C)  K = 0

(D)  K = 0.528

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15. In a uniformaly doped abrupt p-n junction, the doping level of the n-side is four time the doping level of the p-side. The ratio of the depletion layer width is

(A)  2.0

(B)  0.5

(C)  1.0

(D)  0.25

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16. LEDs have response time of the order of

(A)  100 ns

(B)  1 ns

(C)  0.1 ns

(D)  1 μs

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17. Zero mean white noise is passed through an ideal low pass filter with cut off at W Hz. The filter output will be uncorrelated at time instants spaced

(A)  

(B)   

(C)   

(D)   

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18. A 4HGz carrier is DSBSC modulated by low pass message signal with maximum frequency of 2 MHz. The resultant signal is to be ideally sampled. The minimum frequency of the sampling in train should be

(A)  4 MHz

(B)  8 MHz

(C)  8.004 GHz

(D)  8 GHz

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19. Which of the following field equations indicate that the free magnetic changes do not exist

(A)   

(B)  ∇ ∙ H = 0

(C)   

(D)  ∇ × H = J

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20. Two isotropic antennas are separated by a distance of two wavelengths. If both the antennas are fed with currents of equal phase and magnitude, the number of lobes in the radiation pattern in the horizontal plane are

(A)  6

(B)  4

(C)  2

(D)  8

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21. Value of R in the oscillator circuit shown in Fig. is so chosen that is just oscillates at an angular frequency of ω. The value of ω and the required value of R will respectively be

(A)  2 × 10⁴ rad/sec, 2 × 10⁴Ω

(B)  10⁵ rad/sec’ 2 × 10⁴Ω

(C)  2 × 10⁴  rad/sec, 10⁵Ω

(D)  10⁵ rad/sec, 10⁵Ω

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22. The following sequence of instruction are executed by an 8085 microprocessor

1000    LXI             SP,    27 FF

1003    CALL                   1006

1006    POP H

The contents of the stack pointer (SP) and the HL, register pair on completion of execution of these instructions are

(A)  SP = 27 FF, HL = 1006

(B)  SP = 27 FD, HL = 1003

(C)  SP = 27 FF, HL = 1003

(D)  SP = 27 FD, HL = 1006

Show Answer

23. A 1 km long microwave link uses two antennas each having 30 dB gain. If the power transmitted by one antenna is a 1 W at 3 GHz, the power received by the other antenna is approximately

(A)  98.6 μW

(B)  76.8 μW

(C)  55.2 μW

(D)  63.4 μW

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24. A rectangular air-filled waveguide has cross section of 4 cm × 10 cm. The minimum frequency which can propagate in the waveguide is

(A)  1.5 GHz

(B)  3.0 GHz

(C)  2.5 GHz

(D)  2.0 GHz

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25. A deterministic signal has the power spectrum given in Fig. The minimum sampling needed to completely represent this signal is

(A)  3 kHz

(B)  2 kHz

(C)  1 kHz

(D)  None of the above

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26. The decoding circuit show in fig. has been used to generate the active low chip select signal for microprocessor peripheral. (The address lines are designated as A2 to A7 for I-O address)

The peripheral will correspond to IO address in the range

(A)  60 H to 63 H

(B)  30 H to 33 H

(C)  A 4 H to A 7 H

(D)  70 H to 73 H

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27. In a J – K flip-flop we have J = 1, K = 1. Assuming the flip flop was initially cleared and then clocked for 6 pulses, the sequence at the Q output will we

(A)  010101

(B)  011001

(C)  010010

(D)  010000

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28. In the MOSFET amplifier of fig, the signal outputs V₁ and V₂ obey the relationship

(A)  V₁ = V₂/2

(B)  V₁ = −2V₂

(C)  V₁ = 2V₂

(D)  V₁ = −V₂/2

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29. shows a mod-K counter. Here K is equal to

(A)  1

(B)  4

(C)  3

(D)  2

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30. The time averaged Poynting vector in W/m², for a wave with  in free space is

(A)   

(B)   

(C)   

(D)   

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31. In the circuit, C₀ is the distributed capacitance of the coil and C is the tuning capacitor. If C = C₁ for the fundamental harmonic frequency and C = C₂ for the second harmonic frequency, then the value of C₀ can be expressed as

(A)   

(B)   

(C)   

(D)   

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32. The 3dB bandwidth of a typical second-rode system with the transfer function  is given by

(A)   

(B)  

(C)   

(D)   

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33. A small concentration of minority carries is injected into a homogeneous semiconductor crystal at one point. An electric field of 10 V/cm is applied across the crystal and this moves the minority carriers a distance of 1 cm is 20 μ The mobility (in cm²/volt.sec)

(A)  5,000

(B)  2,000

(C)  1,000

(D)  500,000

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34. v(t) = 5[cos(10⁶πt) – sin(10³πt) x sin (10⁶πt)] represents

(A)  AM signal

(B)  DSB suppressed carrier signal

(C)  SSB upper sideband signal

(D)  Narrow band FM signal

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35. The drift velocity of electros, in silicon

(A)  is proportional to the electric field for all values of electric field

(B)  is independent of the electric field

(C)  increase linearly with electric field at low values of electric field and gradually saturates at higher values of electric field       

(D)  increases at low values of electric field and decreases at high values of electric field exhibiting negative differential resistance

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36. The diffusion potential across a P-N junction

(A)  does not depend on doping concentrations

(B)  increases with decreasing band gap

(C)  decreases with increasing doping concentration

(D)  increases with increase in doping concentrations

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37. The output of the circuit show in Fig. is equal to

(A)  1

(B)  0

(C)   

(D)   

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38. A 12-bit ADC is operating with a 1μ sec clock period and the total conversion time is seen to be 14μ The ADC must be of the

(A)  flash type

(B)  integrating type

(C)  counter type

(D)  successive approximation type

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39. A uniform plane wave in air is normally incident on an infinitely thick slab. If the refractive index of the glass slab is 1.5 then the percentage of the incident power that is reflected from the air-glass interface is

(A)  100%

(B)  4%

(C)  20%

(D)  0%

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40. A silicon a MOSFET has a threshold voltage of 1 V and oxide thickness of 400 A°. [ε_r (SiO₂) = 3.9, ε₀ = 8.854 × 10⁻¹⁴ F/cm, q = 1.6 × 10⁻¹⁰ C]. The region under the gate is ion implanted for threshold voltage tailoring. The dose and type of the implant (assumed to be a sheet charge at the interface) required to shift the threshold voltage to −1Vare

(A)  1.08 × 10¹²/cm², p – type

(B)  1.08 × 10¹²/cm², n – type

(C)  5.4 × 10¹¹/cm², n – type

(D)  5.4 × 10¹¹/cm², p – type

Show Answer

41. For a flip-flop formed from two NAND gates as shown in fig. The unusable state corresponds to

(A)  X = 0, Y = 0

(B)  X = 0 , Y = 1

(C)  X = 1, Y = 0

(D)  X = 1, Y = 1

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42. Fig. shows the electrostatic vertical deflection system of CRT. Given that V_A is the accelerating voltage, the deflection sensitivity (deflection/volt) is proportional to

(A)   

(B)   

(C)   

(D)   

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43. Fig. shows the input attenuator of a multimeter. The meter reads full scale with 12V at M, with the range switch at position ‘q’. What is the required voltage at M to obtain full scale deflection with the range switch at position ‘s’?

(A)  1 V

(B)  120 V

(C)  150 V

(D)  147 V

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44. Viewed from the terminals A, B the following circuit shown in fig. can be reduced to an equivalent circuit of a single voltage source in series with a single resistor with the following parameters

(A)  5 volt source in series with 10Ω resistor

(B)  1 volt source in series with 2.4Ω resistor

(C)  1 volt source in series with 10Ω resistor

(D)  15 volt source in series with 2.4 Ω resistor   

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45. The phase lead compensation is used to

(A)  increase rise time and decrease overshoot

(B)  decrease rise time and increase overshoot

(C)  increase both rise tie and overshoot

(D)  decrease both rise time and overshoot

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46. Gauss-Seidal iterative method can be used for solving a set of

(A)  linear algebraic equations only

(B)  linear differential equations only

(C)  both linear and non-linear algebraic equations

(D)  both linear and nonlinear differential equations

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47. For the system shown in fig. with a damping ratio ζ of 0.7 and an undamped natural frequency ω_n of 4 rad/sec, the values of K an a are

(A)  K = 4, a = 0.35

(B)  K = 64, a = 0.9

(C)  K = 16, a = 0.225

(D)  K = 8, a = 0.455

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48. A water boiler at home is switched on to the a.c. mains supplying power at 230 V/50 Hz. The frequency of instantaneous power consume by the boiler is

(A)  0 Hz

(B)  150 Hz

(C)  100 Hz

(D)  50 Hz

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49. In the circuit shown in fig. X is an element which always absorbs power. During a particular operations, it sets up a current of 1 amp in the direction shown and absorbs a power P_x. It is possible that X can absorb the same power P_x for another current i, the value of this current is

(A)   

(B)   

(C)  5 amps

(D)  none of these

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50. Two concentric square loops A and B carry equal currents in the same direction. The magnetic field at O due to the two loops A and B will be in the ratio

(A)  1 : 1.414

(B)  2 : 1

(C)  1.414 : 1

(D)  1 : 1

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PAPER-II

51. The amplitude modulated waveform s(t) = A_c[1 + K_am(t)] cos ω_ct is fed to an ideal envelope detector. The maximum magnitude of K_am(t) is greater than 1. Which of the following could be the detector output?

(A)  A_cm(t)

(B)  A_c[1 + K_am(t)]²

(C)  |A_c[1 + K_am(t)]

(D) 

Show Answer

52. An 8 bit successive approximation analog to digital converter has a full scale reading of 2.55 V and its onversion time for an analog input of 1V is 20

(A)  40 μs

(B)  20 μs

(C)  10 μs

(D)  50 μs

Show Answer

53. Maximum phase-lead of the compensator  is

(A)  55 degrees at 12 rad/sec

(B)  52 degrees at 10 rad/sec

(C)  52 degrees at 4 rad/sec

(D)  None of these

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54. The characteristic equation of a feedback control system is 2s⁴ + s³ + 3s² + 5s + 10 = 0. The number of roots in th right half of s-plane are

(A)  0

(B)  3

(C)  2

(D)  1

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55. A step down chopper operate from a dc voltage source V_s and feeds a dc motor armature with a back emf E_b. From oscilloscope traces, it is found that the current increases for time t, falls to zero over time t_f and remins zero for time t_o in every chopping cycle. Then the average dc voltage across the freewheeling diode is

(A)   

(B)   

(C)   

(D)   

Show Answer

56. A dual-slope analog-to-digital converter uses an N-bit counter. When the input signal V_a is being integratd, the counter is allowed to count up to a value

(A)  equal to 2^N – 1

(B)  equal to 2^N – 2

(C)  proportional to V_a

(D)  inversely proportional to V_a

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57. A current of [2 + √2 sin(314t + 30°) + 2√2 cos (952t + 45°)] is measured with a thermocouple type, 5 A full-scale, class 1 meter. The meter reading would lie in the range.

(A)  5A ± 1%

(B)  2A ± 2.5%

(C)  3A ± 1.7%

(D)  (2 + 3√2) A ± 1%

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58. The voltage phasor of a circuit is V and the current phasor is  The active and the reactive powers in the circuit are

(A)  10 W and 1732 VAR

(B)  5 W and 8.66 VAR

(C)  20√2 W and 10√2 VAR

(D)  20 W and 60 VAR

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59. A fixed capacitor of reactance –j0-02Ω is connected in parallel across a series combination of a fixed inductor of reactance j0.01Ω and a variable resistance R. As R is varied from zero infinity, the diagonal of the admittance of this L-C-R circuit will be

(A)  a semi-circle of diameter j 50 and center at zero

(B)  a semi-circle of diameter j 100 and center at zero

(C)  a straight line inclined at an angle

(D)  a straight line parallel to the x-axis

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60. The function corresponding to the Bode plot of fig. is

(A)  A = j f/f₁

(B)  A =1/(1 – j f₁/f)

(C)  A = 1/(1 + J f₁/f)

(D)  A = 1 + j f/f₁

Show Answer

61. A parabolic dish has a diameter of 10 m. The maximum possible (ideal) gain of the antenna at λ = 314 cm will be

(A)  50 dB

(B)  40 dB

(C)  30 dB

(D)  60 dB

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62. Microwave antenna aperture efficiency depends on

(A)  feed pattern

(B)  surface losses

(C)  antenna aperture

(D)  low side lobe level

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63. Which one of the following is the Fourier transform of the signal given in Figure (i) if the Fourier transform of the signal in Figure (ii) is given by  ?

(A)   

(B) 

(C)    

(D) 

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64. A conductor having surface density σ is embedded in a dielectric medium of permittivity ε. The electric field in the medium is E. If it is known that the pressure p on the conductor surface is equal to the electric energy density in the medium, then p (in SI units) is given by

(A) 

(B)   

(C)   

(D)   

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65. The semiconductor diode which can be used in switching circuits at microwave range is

(A)  Gunn diode

(B)  varactor diode

(C)  tunnel diode

(D)  PIN diode

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66. Noise temperature (T) and gain (G) are two important parameters of satellite antennas. Which one of the following antennas has the largest G/T ratio?

(A)  Parabolic reflector

(B)  Pyramidal horn antenna

(C)  Cassegranian antenna

(D)  Dipole antenna

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67. A square waveguide carries TE₁₁ mode whose axial magnetic field is given by  where the waveguide dimensions are in centimeters. What is the cut-off frequency of the mode?

(A)  6.5 GHz

(B)  7.5 GHz

(C)  5 GHz

(D)  8 GHz

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68. Under what condition will the instrumentation amplifier circuit given in the figure possess highest CMRR? (R_s1 and R_s2 source resistances)

(A)   

(B)   

(C)   

(D)   

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69. In the root-locus for open-loop transfer function   the break away and break in points are located respectively at

(A)  −7.73 and +4.27

(B)  −2.47 and −3.77

(C)  −4.27 and −7.73

(D)  −2 and −1

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70. An amplifier operating over the frequency range o f 18 to 20 MHz has a 10k Ω input resistance. The RMS noise voltage at the input to the amplifier at ambient temperature of 27℃ is (Assume the Boltzman constant value as 1.38 × 10⁻²³ J/K)

(A)  16.2 microvolts

(B)  17.2 microvolts

(C)  18.2 microvolts

(D)  14.2 microvolts

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71. An infinite number of concentric rings carry a charge Q each alternately positive and negative. Their radii are 1, 2, 4, 8 .. meters in geometric progression as shown. The potential at the centre of the will be

(A)   

(B)   

(C)   

(D)   

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72. If the vector  represents a magnetic field, then the value of k must be

(A)  −1

(B)  2

(C)  1

(D)  −2

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73. Two isotropic antennas are separated by a distance of two wavelengths. If both the antennas are with currents of equal phase and magnitude, the number of lobes in the radiation pattern in the horizontal plane is

(A)  2

(B)  6

(C)  4

(D)  8

Show Answer

74. In a rectangular cavity resonator having a = width, b = height and d = length for a > b < d. the dominant mode is

(A)  TE₁₀₁

(B)  TM₁₁₀

(C)  TE₁₁₀

(D)  TM₁₀₁

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75. The arrangement shown in figure represents an RC potentiomer for measuring ac voltage. What should be the value of C so that V₀/V_in is independent of the frequency of the input signal?

(A)  0.10 μF

(B)  11 μF

(C)  10 μF

(D)  0.09 μF

Show Answer

76. The Q factor of a radio coil is

(A)  independent of frequency

(B)  increases monotonically as frequency increases

(C)  increases upto a certain frequency and then decreases beyond that frequency

(D)  decreases monotonically as frequency increases

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77.Which of the following oriented graphs have the same fundamental loop matrix?

Select the correct answer using the codes given below:

(A)  1 and 2

(B)  1, 3 and 4

(C)  2 and 3

(D)  2, 3 and 4

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78. The logic circuit given below converts a binary code y₁y₂y₃ into

(A)  Excess-3 code

(B)  BCD code

(C)  Gray code

(D)  Hamming code

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79. A control system is as shown in figure. The maximum value of gain K for which the system is stable is

(A)  √3

(B)  4

(C)  3

(D)  5

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80. The demarcation between Fresnel region and Fraunhofer region fairly approximated by minimum distance between antennas for pattern measurement is (given that R = distance between antennas, D = largest aperture dimension and λ = wavelength)

(A)  R = 2 D²/λ²

(B)  R = λ²/2 D²

(C)  R = 2 D²/ λ

(D)  R = λ/2 D²

Show Answer

81. Measurement of Hall Effect coefficient in a semiconductor provides information on the

(A)  sign of charge carriers alone

(B)  mass and concentration of charge carriers

(C)  sign and mass of charge carriers

(D)  sign and concentration of charge carriers

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82. The circuit shown in figure is a

(A)  monostable multivibrator

(B)  bootstrap sweep circuit

(C)  Miller sweep circuit

(D)  frequency division circuit

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83. The input pulses to the different stages of the counter shown in figure must be of

(A)  constant frequency and constant width

(B)  variable frequency but constant width

(C)  constant frequency but variable width

(D)  variable frequency as well as variable width

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84. The capacity of an analog communication channel with 4 kHz bandwidth and 15 dB SNR is approximately

(A)  20,000 bps

(B)  8,000 bps

(C)  10,000 bps

(D)  16,000 bps

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85. Which one of t he following is a transferred electron device?

(A)  BARITT diode

(B)  Gunn diode

(C)  IMPATT diode

(D)  Step recovery diode

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86. The slow-wave structures of a TWT is provided with an attenuator. Which one of the following is the function of such an attenuator?

(A)  It prevents the RF power from reaching the output of the device when the beam is switched on

(B)  It reduces the noise level of the device

(C)  It prevents oscillations in the device

(D)  It is used to broadband of the device

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87. On a resistively terminated high frequency loss-less transmission line fed by a 500 MHz source, the VSWR is found to be equal to 2 and the first voltage minimum is measured at 30 cm from the load end. What is the value of the “normalized” load resistance?

(A)  3

(B)  2

(C)  1/4

(D)  1/2

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88. In the voltage regulator shown in Fig. the load current can vary from 100 mA to 500 mA. Assuming that the Zener diode is ideal (i.e., the Zener knee current is negligibly small and Zener resistance is zero in the breakdown region), the value of R is

(A)  7Ω

(B)  70Ω

(C)    

(D)  14Ω

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89. Assume that the op-amp of fig. is ideal. If v_i is a triangular wave, then v_­0 will be

(A)  triangular wave

(B)  square wave

(C)  parabolic wave

(D)  sine wave

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90. Two carriers 40 MHz and 80 MHz respectively are frequency modulated by a signal of frequency 4 kHz, such that the band-widths of the FM signal in the two cases are the same. The peak value deviation in the two cases are in the ratio of

(A)  1 : 4

(B)  1 : 2

(C)  1 : 1

(D)  2 : 1

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91. What is the slope change at ω = 10 of the magnitude v/s frequency characteristic of a unity feedback system with the following open-loop transfer function?

(A)  −40 dB/dec to −20 dB/dec

(B)  −20 dB/dec to −40 dB/dec

(C)  40 dB/dec to 20 dB/dec

(D)  40 dB/dec to −20 dB/dec

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92. For the circuit shown in the figure, the instantaneous current i_i(t) is

(A)   

(B)   

(C)  5∠60° amps

(D)  5∠−60° amps

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94. A JFET is set up as source follower. Given, μ = 200, r_d = 100 K and source load resistance R_L = 1 K. The output resistance R₀ is given approximated by

(A)  1000Ω

(B)  500 Ω

(C)  333 Ω

(D)  666 Ω

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95. The given figure shows a reflectometer arrangement to measure the parameters of an over coupled one-port cavity resonator at f₀. With 100 mW of input power, the output power at B is 6.4 mW. What is the value of the coupling coefficient represent?

(A)  9

(B)  2.5

(C)  5

(D)  6.4

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96. Two coils having equal resistances but different inductances are connected in series. The time constant of the series combination is the

(A)  sum of the time constants of the individual coils

(B)  average of the time constants of individual coils

(C)  geometric mean of the time constants of the individual coils

(D)  product of the time constants of the individual coils

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97. An antenna of input resistance 73Ω is connected to a 50Ω If losses are ignored, then its efficiency will be nearly

(A)  0.19

(B)  0.81

(C)  1.19

(D)  0.97

Show Answer

98. A uniform plane electromagnetic wave travelling in free-space enters into a lossless medium at normal incidence. In the medium its velocity reduces by 50% and in free-space sets up a standing wave having a reflection coefficient of −125. The permeability of the medium is,

(A)  2.57 μ₀

(B)  1.60 μ₀

(C)  1.26 μ₀

(D)  3.5 μ₀

Show Answer

99. In the graph shown in fig. for the tree with branches b, d and f, the fundamental loops would include

1, 2, 3, 4 are nodes

a, b, c, d, e f are branches

(A)  abc, def, bdea

(B)  adb, def, bfa

(C)  cea, bdea, abc

(D)  abde, def, cdb

Show Answer

100. An amplifier without feedback has a gain of 1000. The gain with a negative feedback of 0.009 is

(A)  1000

(B)  10

(C)  100

(D)  125

Show Answer

PAPER-III

101. “Dakshina Gangotri” is

(A)  The place from where Ganga originates

(B)  first nuclear submarine acquired by India

(C)  India’s permanent station at Antartica

(D)  A tributary or river Ganges

Show Answer

102. Which one of the following rulers built the Bibi Ka Maqbara?

(A)  Akbar

(B)  Shahjahan

(C)  Jahangir

(D)  Aurangzeb

Show Answer

103. Hunter Commission was appointed by the British Government to probe into

(A)  Chauri Chaura incident

(B)  demolition of Kanpur Mosque

(C)  Kakori train dacoity incident

(D)  Jalianwalla Bagh tragedy

Show Answer

104. Chilka lake is situated in

(A)  Andhra Pradesh

(B)  West Bengal

(C)  Assam

(D)  Orissa

Show Answer

105. India’s fifth Atomic power plant is being constructed is

(A)  Narora (U.P.)

(B)  Kaiga (Karnataka)

(C)  Kakrapar (Gujarat)

(D)  Rawa bhata (Rajasthan)

Show Answer

106. What does Angstrom measure?

(A)  Intensity of light

(B)  speed at flowing water

(C)  volume of liquids

(D)  Length of light waves

Show Answer

107. The phenomenon of “midnight Sun” is caused by the

(A)  inclination of earth’s axis

(B)  rotation of the earth on its axis

(C)  sun spots

(D)  nuclear explosions

Show Answer

108. Which one of the following is associated with the Gupta Age of Indian history?

(A)  Visit of Chinese pilgrim Husan Tsang

(B)  Significant contribution to poetry and literature by Banabhatta

(C)  Significant contribution to Indian astronomy by Aryabhatta

(D)  Macedonian invasion

Show Answer

109. Under-12 World Chess Championship in 1998 was won by

(A)  Tejas Bakre

(B)  Koneru Humpy

(C)  Vijayalakshmi

(D)  Dibyendu Barua

Show Answer

110. One of the most important foreign exchange earning herbs used in the treatment of several kinds of chronic dysentery is

(A)  Isabgol

(B)  Tulsi

(C)  Madhuca

(D)  Rauwolfia

Show Answer

111 to 114 : Direction-Read the passages that follows. The questions at the end of teach passage are based on the content to the passage. Choose your answers from the choice mentioned.

The need for sola electricity is clear. It is safe, ecologically sound, efficient, continuously available, and it has no moving parts. The basic problem with the use of solar photovoltaic devices is economics, but until recently every  little progress had been made towards the development of low-cost photovoltaic devices. The larger part of research funas has been devoted to study of single-crystal silicon solar cells, despite the evidence, including that of the leading manufacturing of crystalline silicon, that this technique holds little promise. The reason for this pattern is understandable and historical. Crystalline silicon is the active element in the very successful semi conductor industry and virtually all of the solid state devices contain silicon transistors and diodes. Crystalline silicon, however is particularly unsuitable to terrestrial solar cells.

Crystalline silicon solar cells work well and are successfully used in the space programme, where cost is not an issue. While single crystal silicon has been p proven in extraterrestrial use with efficiencies as high as 18% and other more expensive and scarce materials such as gallium arsenide can have even higher efficiencies, costs must be reduced by a factor of more than 100 to make them practical for commercial uses. Besides the fact that the starting crystalline silicon is expensive, 95% of it is wasted and does not appear in the final device. Recently there have been some imaginative attempts to make polycrystalline and ribbon silicon that are lower in cost than high quality single crystals; but to data the efficiencies of these apparently lower-cost arrays have been unacceptably small. Moreover, these materials are cheaper only because of the introduction of disordering in crystalline semiconductors, and disorder degrades the efficiency of crystalline solar cells.

The dilemma can be avoided by preparing completely disordered or amorphous materials Amorphous materials have disordered atomic structure as compared to crystalline materials, that is, they have only short-range order rather than the long-range periodicity of crystals. The advantage of amorphous solar cells are impressive. Whereas crystals can be grown as wafers about 4 inches in diameter, amorphous materials can be grown over large areas in a single process. Whereas crystalline silicon must be made 200 microns thick to absorb a sufficient amount of sun light for efficient energy conversion, only 1 micron of the proper amorphous materials is necessary. Crystalline silicon solar cells cost in excess of Rs. 100 per square foot, but amorphous films can be created at a cost of about 50 paise per square foot.

Although many scientists were aware of the very low cost of amorphous solar cells, they felt that they could never be manufactured with the efficiencies necessary to contribute significantly to the demand for electric power. This was based on a misconception about the feature which determines efficiency. For example, it is not the conductivity of the material in the dark that is relevant that only the photoconductivity, that is, the conductivity in the presence of sunlight. Already, solar cells with efficiencies will above 6% have been developed using amorphous materials and further research will doubtless find even less costly amorphous materials with higher efficiencies.

111. The material in the passage could best the used in an argument for

(A)  discontinuing the space programme

(B)  further study of the history of silicon crystals

(C)  increased funding for research on amorphous materials

(D)  increased reliance on solar energy

Show Answer

112. The author mentions which of the following as advantages of amorphous materials for solar cells over silicon crystals?

I. the relative thinness of amorphous materials

II. the cost of amorphous materials

III. the size of solar cells which can be made of amorphous material

(A)  I and II only

(B)  II only

(C)  I only

(D)  II and III only

Show Answer

113. The tone of the passage can best be described as

(A)  analytical and optimistic

(B)  tentative and inconclusive

(C)  critical and discouraged     

(D)  biased and unprofessional

Show Answer

114. The author is primarily concerned with

(A)  explaining the functioning of solar cells

(B)  discussing the importance of solar energy

(C)  presenting a history of research on energy sources

(D)  describing a possible solution to the problem of the cost of photovoltaic cells

Show Answer

Questions (115 to 116): Direction- In this section a number of sentences are given. The sentences are underlined in three separate parts and each one is labeled (a), (b), (c). Read each sentence to find out whether there is an error in any underlined part. No sentence has more than one error. When you find an error in any one of the underlined parts (a), (b) or (c), indicates your response on the separate Answer Sheet at the appropriate space. You may feel that there is no error in a sentence. In that case letter (d) will signify a ‘No error’ response.

115. Perhaps the governments too in its efforts

                      (a)

to make the  truth being know

                      (b)

should take some sincere steps in that direction

                        (c)

No error

   (d)

Show Answer

116. An open administration will not help

               (a)

if government rules are complicated and incomprehensible

              (b)

for the affected public

             (c)

No error

(d)

Show Answer

117. Find the most similar word in meaning

BRAGGADOCIO

(A)  encounter

(B)  boasting

(C)  weaponry

(D)  position

Show Answer

118. Find the most similar word in meaning

INCORRIGIBLE

(A)  narrow

(B)  unreformable

(C)  inconceivable

(D)  straight

Show Answer

119. Find the opposite word in meaning

CARNAL

(A)  actual

(B)  minute

(C)  spiritual

(D)  impressive

Show Answer

120. Find the opposite word in meaning

JETTISON

(A)  salvage

(B)  descend

(C)  submerge

(D)  decelerate

Show Answer

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BSNL Junior Telecom Officers’ (JTO) Recruitment Exam Question Paper 2014 With Answer Key

BSNL Junior Telecom Officers’ (JTO) Recruitment Exam Question Paper 2008 With Answer Key

BSNL Junior Telecom Officers’ (JTO) Recruitment Exam Question Paper 2005 With Answer Key

BSNL Junior Telecom Officers’ (JTO) Recruitment Exam Question Paper 2002 With Answer Key

BSNL Junior Telecom Officers’ (JTO) Recruitment Exam Question Paper 2001 With Answer Key

BSNL J.T.O Recruitment Exam 2002

Paper-I

1. Two capacitors are connected in series. The first capacitor is of capacitance 40 μF and break down voltage 60 V and capacitance of second capacitor is 60 μF and break down voltage is 40 V. What condition is satisfied?

(A)  First capacitor  break down is first

(B)  The charge equal to the both capacitor

(C)  Second capacitor break down is first

(D)  None of these

Show Answer

2. What is the state equation for the nth order of differential equation,

(A)  (n – 1)²

(B)  (n + 1)

(C)   

(D)  n

Show Answer

3. If there are be branches and n nodes, the number of KCL equations required will be

(A)  n

(B)  b

(C)  (n – 1)

(D)  b – n + 1

Show Answer

4. Maxwell’s divergence equation for the magnetic field is given by

(A)  ∇ × E = 0

(B)  ∇ × B = 0

(C)  ∇ ∙ B = 0

(D)  None of these

Show Answer

5. For an SCR, with L I n series with SCR. What type of protection is

(A)   

(B)   

(C)  Voltage protection

(D)  None of these

Show Answer

6. For series connected SCRs, dynamic equalizing circuit consists of

(A)  Resistor R and capacitor C in series but with a diode D across C

(B)  Series R and D circuit but with across R

(C)  Series C and D circuit but with R across C

(D)  Series R and C but with D across R

Show Answer

7. In the three-phase converter α is in the range 0 < α < 90. When it operates in inverter the range of α is

(A)  90 < α ≤ 180

(B)  0 < α < 90

(C)  180 < α ≤ 270

(D)  None of these

Show Answer

8. In a circuit the current transform  The value of i(t) at t → ∞ is

(A)  5

(B)  1/2

(C)  6

(D)  ∞

Show Answer

9. In inverted operation of a transistor

(A)  both junctions are reverse biased

(B)  both junctions are forward biased

(C)  emitter junction is forward biased while collector junction is reversed  biased

(D)  emitter junction is reversed biased while collector junction is forward biased

Show Answer

10. How many loop current is the cut-set analysis?

(A)  3

(B)  5

(C)  4

(D)  None of these 

Show Answer

11. The steady state voltage of the capacitor is

(A)  2V

(B)  1V

(C)  0V

(D)  0.5V

Show Answer

12. A capacitor of capacitance c₁ and distance between the plate is d₁. A second capacitor of capacitance c₂ and distance between the plate is d₂. When they are connected to series, what is the equivalent capacitance?

(A)   

(B)   

(C)   

(D)   

Show Answer

13. In a circuit voltage in the inductor is 2V and inductance of the inductor is 1 mH. What is the rate of current decay?

(A)  2 × 10³ A/S

(B)  1 × 10³ A/S

(C)  2 A/S

(D)  None of these

Show Answer

14. In a circuit current passing the capacitor is 1A. The capacitance of thee capacitor is 1 μ Find the voltage decay of the capacitor?

(A)  1 × 10³ A/s

(B)  1 V/S

(C)  2 × 10³ V/S

(D)  None of these

Show Answer

15. Two capacitors of capacitance 1 μF each. When they are connected in parallel, what is the resultant capacitance?

(A)  0.5 μF

(B)  2 μF

(C)  1 μF

(D)  None of these

Show Answer

16. Who was the first to give the theory of electro magnetic induction?

(A)  Faraday

(B)  Maxwell

(C)  Ampere

(D)  None of these

Show Answer

17. A 3-phase 50 Hz, 6 pole squirrel case induction motor will run at a speed approximately

(A)  1600 rpm

(B)  1000 rpm

(C)  1500 rpm

(D)  960 rpm

Show Answer

18. The electron and hole concentrations in an intrinsic semiconductor are n_i and p_i When doped p type material, these change to n and p respectively, then

(A)  n + p = n_i + p_i

(B)  n + n_i = p + p_i

(C)  np = n_ip_i

(D)  np_i = n_ip

Show Answer

19. In a full-wave rectifier the supply frequency is 50 Hz. What is the ripple frequency?

(A)  25 Hz

(B)  100 Hz

(C)  50 Hz

(D)  None

Show Answer

20. In a vector field, given condition is,  and  The vector  is not null vector, which of the following condition satisfies the equation

(A) 

(B)   

(C)   

(D)   

Show Answer

21. The diffusion potential across p-n junction

(A)  decreases with increasing doping concentration

(B)  does not depend on doping concentration

(C)  increases with decreasing band gap

(D)  increases with increase in doping concentration

Show Answer

22. In a bipolar transistor at room temperature, if the emitter current is doubled, the voltage across its base-emitter junction

(A)  doubles

(B)  increases by about 20 mV

(C)  halves

(D)  decreases by about 20 mV

Show Answer

23. In a series RLC circuit, at the resonant frequency

(A)  current is maximum

(B)  voltage across C is maximum

(C)  impedance is maximum

(D)  current is minimum

Show Answer

24. When a voltage v₀ sin w₀t is applied to the pure inductor, the ammeter shown in the figure reads I₀. If the voltage applied is –V₀ sin w₀t + 2V₀ sin 2 w₀t + 3V₀ sin 3w₀t + 4 V₀ sin 4w₀t the ammeter reading would be

(A)  10 I₀

(B)  0

(C)    

(D)  2I₀

Show Answer

25. The average power flow per unit area in a uniform plane wave in an electric field of maximum voltage E₀ and impedance z₀ is

(A)   

(B)   

(C)   

(D)   

Show Answer

26. Precision measurement of resistance is generally carried out by

(A)  Potentiometer method

(B)  Voltmeter-ammeter method

(C)  CRO method

(D)  Bridge method

Show Answer

27. A galvanometer is tested as shown in the figure, in the circuit where E = 1.5 V, R₁ = 1.0 ohm, R₂ = 2500 ohm and R₃ is variable. With R₃ set at 450 ohm, the galvanometer deflection is 140 mm and with R₃ set at 950 ohm, the galvanometer deflection is 70 mm. The resistance of the galvanometer is

(A)  29 ohms

(B)  49 ohms

(C)  99 ohms

(D)  10 ohms

Show Answer

28. A double tuned circuit amplifier provides

(A)  high gain for pass band frequencies

(B)  more flat response for all frequencies

(C)  less harmonic distortion

(D)  more flat response for all pass band frequencies

Show Answer

29. Dual slope integration type Analog-to-Digital converters provide

(A)  higher speeds compared to all other types of A/D converters

(B)  poor rejection of power supply current

(C)  very good accuracy without putting extreme requirements on component stability

(D)  better resolution compared to all other types of A/D converters for the same number of bits

Show Answer

30. Rhombic antenna is a

(A)  resonant antenna

(B)  non-resonant antenna

(C)  directional high frequency antenna

(D)  none of these

Show Answer

31. In a single phase ne-pulse circuit with RL load and a freewheeling diode, extinction angle β is less than π. For a firing angle α, the SCR and freewheeling diode would respectively, conductor for

(A)  (β – α), 0°

(B)  α, (β – α)

(C)  (π – α), (π – β)

(D)  (β – α), α

Show Answer

32. A CRO can display

(A)  d.c. signals

(B)  a.c. signals

(C)  both a.c. and d.c. signals

(D)  none of these

Show Answer

33. In two wattmeter method of measuring 3-phase power, power factor is 0.5, then one of the wattmeter will read,

(A)  W/2

(B)  W/√3

(C)  √2 W

(D)  Zero

Show Answer

34. A 100 mA meter has accuracy of ±2 percent. Its accuracy while reading 100 mA will be

(A)  ± 4%

(B)  ± 9%

(C)  ± 0.2%

(D)  ± 20%

Show Answer

35. In moving-coil instrument, the scale used is

(A)  Linear scale

(B)  Non-linear scale

(C)  Square law scale

(D)  Log scale

Show Answer

36. Two meters X and Y required 40 mA and 50 mA respectively, to give full-scale reflection, then

(A)  X is more sensitive

(B)  both are equally sensitive

(C)  Y is more sensitive

(D)  sensitivity can not be judged with the given information  

Show Answer

37. If D_n represents the ratio of amplitudes of nth harmonics to the fundamental components of a signal, then distortion factor of the signal will be

(A)   

(B)   

(C) 

(D)   

Show Answer

38. An RC-couple amplifier has an open loop gain of 100 and a upper cut off frequency of 100 kHz. If negative feedback with a feedback with a feedback factor 0.02 is used, the upper cut off frequency will be

(A)  300 kHz

(B)  33.3 kHz

(C)  100 kHz

(D)  1000 kHz

Show Answer

39. In a LVDT, the two secondary voltages

(A)  vary equally depending on the core position

(B)  vary unequally depending on the core position

(C)  are independent of the core position

(D)  are always in phase quadrature

Show Answer

40. A metal strain guage has factor of 2. Its nominal resistance is 120 ohms. It undergoes strain at 10⁻⁵, the value of change of resistance in response to the strain is

(A)  2 × 10⁻⁵ ohms

(B)  2 × 10⁵ ohms

(C)  240 ohms

(D)  2.4 × 10⁻³ ohms

Show Answer

41. What is machine cycle in SIM instruction?

(A)  2

(B)  1

(C)  3

(D)  4

Show Answer

42. How many J-K flip-flop is required in 5-modulo synchronous converter?

(A)  4

(B)  5

(C)  2

(D)  3

Show Answer

43. Given that the electric field in electromagnetic wave is E = 10e^{(6x + 8y)}a_x. What is the wave speed?

(A)  10⁹ m/s

(B)  10⁸ m/s

(C)  10⁷ m/s

(D)  10¹⁰ m/s

Show Answer

44. Given that E_x = E_x sin (ωt + ϕ) and E_y = E_y sin(ωt + ϕ). These are which types of polarization?

(A)  Straight line

(B)  Left circulation

(C)  Parabolic

(D)  Right circulation

Show Answer

45. The data bus width of a 4 × 1024 bits is

(A)  13

(B)  11

(C)  12

(D)  10

Show Answer

46. In the current-shunt feedback

(A)  High input and output impedance

(B)  High input and low output

(C)  Low input and low output

(D)  Low input and high output

Show Answer

47. The following program is run on an 8085 microprocessor

At the completion of execution of the program, the program counter of the 8085 contains… and the stack point contains…..

(A)  2000, CCFO

(B)  2020, OCCF

(C)  2050, OFFC

(D)  2020, OFFC

Show Answer

48. A parabolic reflector is designed to have directivity of 30 dB at 300 MHz. If the apeature efficiency is 55%, then the diameter of reflector is

(A)  3 m

(B)  4 m

(C)  2 m

(D)  None of these

Show Answer

49. A rectangular waveguide a = 5 cm, b = 3.75 cm and the frequency is 10 GHz, the wave length is 7 cm. Which of the following is mode of operation of wave guide?

(A)  TE₁₁

(B)  TE₁₀

(C)  TM₀₁

(D)  TE_2.0

Show Answer

50. The logic realized by the circuit shown in the figure is

(A)  F = B . C

(B)  F = A ⊕ C

(C)  F = A . C

(D)  F = B ⊕ C

Show Answer

PAPER-II

51. Maximum voltage is induced in a loop antenna if

(A)  it is parallel to the incoming wave

(B)  it is placed at right angles to the incoming wave

(C)  its width is more than λ/2

(D)  it is placed at 45° to the incoming wave

Show Answer

52. When a route carriers no subscriber dialed traffic, the internationally accepted worst grade of service is

(A)  10%

(B)  3%

(C)  1%

(D)  20%

Show Answer

53. A microstrip line on alumina substrate (∈_t = 9)has a zero thickness strip of width, W = 3 mm. Substrate thickness h = 0.5 mm. Assuming TEM wave propagation and negligible fringing field, the characteristic impedance of the line will be approximately

(A)  10 ohm

(B)  50 ohm

(C)  26 ohm

(D)  21 ohm

Show Answer

54. The effective inductance of the circuit across the terminal AB in the figure shown below, is

(A)  9 H

(B)  21 H

(C)  6 H

(D)  11 H

Show Answer

55. The MOSFET switch in its on-state may be considered equivalent to

(A)  Capacitor

(B)  Inductor

(C)  Resistor

(D)  Battery

Show Answer

56. Two parallel wires separated by a distance d are carrying a DC current I in the same direction. The magnetic field along a line running parallel to these wire and midway between them

(A)  zero

(B)  depends upon I

(C)  depends upon d

(D)  depends upon the permeability of the medium between the wires

Show Answer

57. A 35 V d.c. supply is connected across a combined resistance of 600 ohms and an unknown resistance of R ohms in series. A voltmeter having a resistance of 1.2 kΩ is connected across 600 ohm resistor and reads 5V. The resistance K will be

(A)  120 ohms

(B)  500 ohms

(C)  2.4 K ohms

(D)  1.7 K ohms

Show Answer

58. CMOS has the following advantage over PMOS/NMOS?

(A)  Lower Dissipation power (P_D)

(B)  Simpler fabrication process

(C)  Lower input capacitance

(D)  Greater suitability for LSI

Show Answer

59. In the circuit shown in figure, it is desired to have a constant direct current i(t) through the ideal inductor L. The nature of the voltage source v(t) must be

(A)  constant voltage

(B)  linearly increasing voltage

(C)  exponentially increasing voltage

(D)  an ideal impulse       

Show Answer

60. The threshold voltage of an n-channel MOFSET can be increased by

(A)  reducing the channel length

(B)  increasing the channel doping concentration

(C)  reducing gate oxide thickness

(D)  decreasing the channel doping concentration

Show Answer

61. For signal amplitude modulated to a depth of 100% by a sinusoidal signal, power is

(A)  same as the power of unmodulated carrier

(B)  3/2 times the power of unmodulated carrier

(C)  twice as the power of unmodulated carrier

(D)  2/3 times the power of unmodulated carrier

Show Answer

62. A series RLC circuit is over-damped when

(A)  

(B)   

(C)   

(D)   

Show Answer

63. In a A/D converter input voltage is ±5V, In a 10 bit converter, what is the error voltage?

(A)  15 mV

(B)  20 mV

(C)  10 mV

(D)  None

Show Answer

64. In a differential amplifier, V₁ and V₂ is input voltage. Common mode rejection ratio is 1000. Which equation represents the output of the amplifier

(A)   

(B)   

(C)   

(D)   

Show Answer

65. Consider a system shown in the given figure with

What value of ‘k’ and ‘a’ should be chosen so that the system oscillates?

(A)  k = 2, a = 1

(B)  k = 4, a = 0.75

(C)  k = 4, a = 1

(D)  k = 2, a = 0.75

Show Answer

66. The Quadrature Amplitude Modulation is a combination of

(A)  PSK and FSK

(B)  ASK and FSK

(C)  ASK and PSK

(D)  None

Show Answer

67. A circuit in which the output voltage remains constant irrespective of the value of load resistance, uses

(A)  Zener diode

(B)  Silicon diode

(C)  SCR

(D)  None of above

Show Answer

68. The input resistance of a MOSFET

(A)  Is of the same order as in a bipolar transistor

(B)  Is low as compared to that of a bipolar transistor

(C)  Is very high as compared to that of a bipolar transister

(D)  None of above

Show Answer

69. A system has characteristic equation as s² + 2s + 8 = 0. The damping ratio and the natural frequency of oscillation of the system respectively are

(A)  2, 0.353

(B)  0.5, 2√2

(C)  0.353, 2√2

(D)  2√2, 0.5

Show Answer

70. For the characteristic equation

s⁴ + 5s³ + 5s² + 4s + k = 0

the system is stable if k lies in the range

(A)   

(B)   

(C)  4 > k > 3

(D)  3 > k > 1

Show Answer

71. The following sequence of instructions are executed by an 8085 microprocessor

1000    LXI             SP     27FF

1000    CALL                   1006

1006    POP H

The contents of the stack pointer (SP) and the HL register pair on completion of execution of these instructions are

(A)  SP = 27 FF, HL = 1003

(B)  SP = 274 FD, HL = 1003

(C)  SP = 27 FF, HL = 1006

(D)  SP = 27 FD, HL = 1006

Show Answer

72. A system with an input x(t) and an output y(t) is described by the relation y(t) = tx(t). This system is

(A)  Linear and time-invariant

(B)  Linear and time varying

(C)  Non-Linear and time-invariant

(D)  Non-linear and time-varying

Show Answer

73. In a 3 big-MUX, the output is the figure is

(A)  I₁ + I₂ + I₃

(B)  I₂ + I₄ + I₅

(C)  I_2­ + I₅ + I₆

(D)  I₁ + I₃ + I₅ + I₇

Show Answer

74. 1 km long microwave link uses to antennas each having 30 dB gain. If the power transmitted by one antenna is 11 μW at 3 GHz, the power received by the other antenna is

(A)  93.6 μW

(B)  55.2 μW

(C)  63.4 μW

(D)  76.8 μW

Show Answer

75. The Fourier transform of a real valued time signal has

(A)  Even symmetry

(B)  Odd symmetry

(C)  Conjugate symmetry

(D)  No symmetry

Show Answer

76. Two-port networks are connected in cascade. The combination is to be represented as a single two port network. The parameters of the network are obtained by multiplying the individual

(A)  ABCD parameters matrix

(B)  h-parameters matrix

(C)  Y-parameters matrix

(D)  Z-parameters matrix

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77. In a single stage transistor amplifier circuit shown in the figure, the capacitance C_E is removed. Then the ac small signal midband voltage gain of amplifier

(A)  increases

(B)  remain’s unaffected

(C)  decreases

(D)  drops to zero

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78. The polar plot of a type-1, 3-pole open-loop system is shown in the figure. The closed loop system is

(A)  Marginally stable

(B)  Always stable

(C)  Unstable with one pole on the right half-splane

(D)  Unstable with two poles on the right half splane

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79. An n-channel JFET, having a pinch-off voltage (V_P) of −5 V shows a transconductance (g_m) of 1 mA/V when the applied gate-to-source voltage (V_GS) is − Its maximum transconductance (in mA/V) is

(A)  1.5

(B)  2.5

(C)  2.0

(D)  3.0

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80. Frequency shift keying is used mostly in

(A)  Telephony

(B)  Telegraphy

(C)  Radio transmission

(D)  None of these

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81. For a shot wave radio link between two stations vis therionsphere, the ratio of the maximum usable frequency to the critical frequency

(A)  Is always greater than 1

(B)  Is always less than 1

(C)  May be ≤ 1 depending on the distance between two stations

(D)  Does not depend on the distance between the two stations

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82. Companding is used

(A)  To protect small signals in PCM from quantizing distortion

(B)  To overcome impulse noise

(C)  To overcome quantized noise in PGM

(D)  None of these

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83. In an 8085 microprocessor system with memory mapped I/O

(A)  I/O devices are accessed using IN and OUT instructions

(B)  I/O devices 16-bit addresses

(C)  There can be a maximum of 256input devices and 256 output devices

(D)  Arithmetic and logic operations can be directly performed with I/O data

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84. A microprocessor with 12 address lines is capable of addressing

(A)  64 K locations

(B)  2028 locations

(C)  4096 locations

(D)  1024 locations

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85. The usable bandwidth of a microwave beacon transponder for 6/4 GHz satellite communication is generally

(A)  40 MHz

(B)  360 MHz

(C)  36 MHz

(D)  1 MHz

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86. A broadcast radio receiver with IF = 455 kHz is tuned to 1500 kHz. The image frequency will be

(A)  1955 kHz

(B)  1500 kHz

(C)  1045 kHz

(D)  2410 kHz

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87. Signal flow graph is used to obtain the

(A)  Observability of the system

(B)  Transfer function of the system

(C)  Controllability of the system

(D)  Stability of the system

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88. Each cell of a static Random Access memory contains

(A)  6 MDS transistors

(B)  XOR gates and shift registers.

(C)  Two 2-inpout NORs and One X-NOR gate

(D)  4 MOS transistors and 2 capacitors

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89. The bit rate of a digital communication system is 34 Mbit/s. The modulation scheme is QPSK. The baud rate of the system is

(A)  17 Mbit/s

(B)  34 Mbit/s

(C)  68 Mbit/s

(D)  8.5 Mbit/s

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90. A circular waveguide has internal diameter of 5 cm. The cutoff frequency for TE₁₁ mode will be

(A)  5 MHz

(B)  35 GHz

(C)  3.5 GHz

(D)  35 MHz

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91. Two usual stables states of a binary are

(A)  cut off and saturation

(B)  cut off and active

(C)  active and saturation

(D)  both in saturation

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92. Harmonic distortion in amplifier is caused by

(A)  defective active device

(B)  presence of noise

(C)  non-linearity in active device

(D)  positive feed back

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93. The AM broadcast band (medium wave band extends from)

(A)  200 kHz to 1000 kHz

(B)  500 kHz to 1600 kHz

(C)  30 MHz to 300 MHz

(D)  3 MHz to 30 MHz

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94. All the output pulses are at full transmitter power for a strong signal in all of the following except

(A)  PWM

(B)  PFM

(C)  PAM

(D)  PCM

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95. The Op-Amp circuit given  below is

(A)  An integrator

(B)  Sample and hold circuit

(C)  A voltage follower

(D)  An inverter

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96. The initial contents of the 4 bit serial-in-parallel out, right-shift. Shift Register shown in the figure is 0110. After three clock pulses are applied, the contents of the shift Register will be

(A)  1111

(B)  0101

(C)  1010

(D)  0000

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97. The block diagram shown below represents

(A)  Modulo-7 synchronous counter

(B)  Modulo-5 ripple counter

(C)  Modulo-7 ripple counter

(D)  Modulo-3 ripple counter

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98. If the carrier of a 100 percent modulated AM wave is suppressed, the percentage power saving will be

(A)  50

(B)  150

(C)  100

(D)  66.66

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99. Bode plots of an open-loop transfer function of a control system are shown in the given figure.

The gain margin of the system is

(A)  −K

(B)  K

(C)  1/K

(D)  −1/K

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100. In a broadcast Superheterodyne receiver, the

(A)  local oscillator operates below the signal frequency

(B)  mixer input must be tuned to the signal frequency

(C)  local oscillator frequency is double the If

(D)  RF amplifier normally works at 456 KHZ above the carrier frequency

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PAPER-III

101. Jonas Salk discovered

(A)  Viagra

(B)  Wet photography

(C)  Silicon devices

(D)  Polio vaccine

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102. Which of the following can be transferred to any human body?

(A)  A −ve

(B)  O −ve

(C)  AB +ve

(D)  None of these

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103. Who directed the movie ‘Mansoon Wedding’?

(A)  Shekhar Suman

(B)  Shekhar Kapoor

(C)  Mira Nair

(D)  Deepa Mehta

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104. Which of the following will not match for the environmental friendly Automobile?

(A)  MPFI

(B)  Catalytic Converters

(C)  Turbo charging

(D)  Electric Ignition

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105. Which of the following is in order of the time of introduction for large scale communication.

1. Fibre optics

2. Under ground cables

3. Satellite communication

4. Total wireless loop

(A)  1, 2, 3, 4

(B)  2, 1, 3, 4

(C)  1, 3, 2, 4

(D)  2, 3, 1, 4

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106. Who said ‘India live in her villages’?

(A)  Jawaharlal Nehru

(B)  Indira Gandhi

(C)  Mahatma Gandhi

(D)  S. Radhakrishnan

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107. The rivers of the Peninsular India originate on the

(A)  Eastern Ghats

(B)  Western Ghats

(C)  Aravallis

(D)  Himalayas

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108. Name the person who held the Finance portfolio twice in India.

(A)  R. K. Shanmugam Chettiar

(B)  C. D. Deshmukh

(C)  T. T. Krishnamachari

(D)  Manmohan Singh

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109. Which State ranks first in the production of food crops in India?

(A)  Uttar Pradesh

(B)  Madhya Pradesh

(C)  Andhra Pradesh

(D)  Himachal Pradesh

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110. Who introduced ‘Own Your Telephone’ scheme in India?

(A)  R. V. Subramanian

(B)  R. A. Kidwai

(C)  C. Subramaniam

(D)  M. M. Singh

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111. What is the percentage of thermal electricity produced in India?

(A)  40

(B)  50

(C)  80

(D)  72

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112. Who is the chairperson of United Nations Human Rights commission?

(A)  P. N. Bhagavati

(B)  Megavati Sukharnoputri

(C)  Sukoto ogada

(D)  Mary Robhson

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113. Convergence bill refers to

(A)  Electronic media

(B)  I.T., Tele communication

(C)  Print media, press, Electronic items

(D)  All of the above

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114. Find the most similar word in the meaning strike a chord

(A)  elicit sympathy

(B)  show anger

(C)  expect sympathy

(D)  cause anger

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115. Find the opposite word in the meaning hostility

(A)  enmity

(B)  friendship

(C)  praise

(D)  love

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116. Which is not clean gas?

(A)  L.P.G.

(B)  C.N.G.

(C)  L.S.D.

(D)  H.S.D.

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117. “Technology Next” is the slogan of which of the following company?

(A)  Philips

(B)  Hewlett factory

(C)  Compaq

(D)  Videocon

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118. Which gas is greenhouse gas?

(A)  Oxygen

(B)  Nitrogen oxide

(C)  Nitric acid

(D)  Carbon dioxide

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119. Author of future shock, Third wave is

(A)  Aldug Hacksley

(B)  Bob Morris

(C)  Norman Mailer

(D)  Arvin Toffler

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120. Author of ‘Wings of fire’ is

(A)  R. K. Narayan

(B)  A. P. J. Abdul Kalam

(C)  P. V. Narasimharao

(D)  C. N. Rao

Show Answer

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