Q.1

Which of the following photodetector does not provide gain?

  • Phototransistor
  • Photoconductor
  • Avalanche photodiode
  • p-i-n photodiode
Q.2

A 2 bit binary multiplier can be implemented using

  • 2 inputs ANDs only
  • 2 inputs XORs and 4 input AND gates only
  • Two 2 inputs NORs and one XNOR gate
  • XOR gates and shift registers
Q.3

The materials not having negative temperature coefficient of resistivity are

  • metals
  • semiconductors
  • insulators
  • none of the above
Q.4

Inmicroprocessor, the interrupt enable flip-flop is reset by

  • DI instruction only
  • system RESET only
  • interrupt acknowledgment only
  • all of the above
Q.5

With which decoder it is possible to obtain many code conversions?

  • 2 line to 4 line
  • 3 line to 8 line
  • not possible with any decoder
  • 4 line to 16 line decoder
Q.6

What are the minimum number of 2 to 1 multiplexers required to generate a 2 input AND gate a 2 input Ex-OR gate?

  • 1 and 2
  • 1 and 3
  • 1 and 1
  • 2 and 2
Q.7

Which of the following stages has no phase inversion of the signal?

  • Two CE stages
  • Three CE stages
  • CE and CC stages
  • CE stage and emitter follower
Q.8

Which of the following flip-flop is used as a latch?

  • J K flip-flop
  • R S flip-flop
  • T flip-flop
  • D flip-flop
Q.9

Consider the following statements:
The klystron and travelling wave tube differ from each other,

  1. In TWT the microwave circuit is non- resonant.
  2. In klystron the microwave circuit is resonant.
  3. TWT uses attenuator.
  4. The wave is TWT is a non-propagating wave.
Which of the above statements are correct?
  • 1 and 2 only
  • 3 and 4 only
  • 1, 2 and 3
  • 2, 3 and 4
Q.10

Manganin, an alloy of copper and manganese, is used in

  • Soldering material
  • Heating elements
  • Ballast resistors
  • Standard resistances
Q.11

If (10)x x (10)x = (100)x; (100)x x (100)x = (10000)x then x can take value :

  • 2
  • 5
  • 10
  • all of these
Q.12

Multiple member of antennas are arranged in arrays in order to enhance what property?

  • Both directivity and bandwidth
  • Only directivity
  • Only bandwidth
  • Neither directivity nor bandwidth
Q.13

Which of the following transducers is most suitable for monitoring continuous variations in very fine thickness of a material?

  • Diaphragm
  • Capacitor
  • L.V.D.T.
  • Piezoelectric crystal.
Q.14

The characteristic equation of a control system is given as s4 + 8s3 + 24s2 + 32s + K =What is the range of values of K for this system to be stable?

  • 0 ≤ K < 80
  • 0 ≤ K < 100
  • 0 ≤ K < 2300
  • 0 ≤ K < 600
Q.15

On which bands, do the optical fibers operate?

  1. Ultra violet band
  2. Ultra high frequency band
  3. Visible light band
  4. Infrared band
Select the correct answer from the codes given below:
  • 1 only
  • 1 and 2 only
  • 1, 2 and only
  • 1, 3 and 4
Q.16

If a two-port network is reciprocal as well as symmetrical, which one of the following relationships is correct?

  • Z12 = Z21 and Z11 = Z22
  • Y12 - Y21 and Y11 - Y22
  • AD - BC = 1 and A = D
  • all of the above
Q.17

What is the characteristic of a good control system?

  • Sensitive to parameter variation
  • Insensitive to input command
  • Neither sensitive to parameter variation nor sensitive to input commands
  • Insensitive to parameter variation but sensitive to input commands
Q.18

What will be equipotential surfaces for a pair of equal and opposite line charges?

  • Spheres
  • Concentric cylinders
  • Non-concentric cylinders
  • None of the above
Q.19

The 4 point Discrete Fourier Transform (DFT) of a discrete time sequence {is

  • [0, - 2 + 2j, 2, - 2 - 2j]
  • [2, 2 + 2j, 6, 2 - 2j]
  • [6, 1 - 3j, 2, 1 + 3]
  • [6, - 1 + 3j, 0, - 1 - 3j]
Q.20

The following components are used to measure power output of a 2 kW TWT amplifier:

  1. TWTA
  2. Low pass/high pass filter
  3. dB attenuator
  4. dB directional complex with matched load
  5. Power load
What is the correct sequence of connection of these components?
  • 2 - 4 - 1 - 3 - 5
  • 1 - 3 - 4 - 2 - 5
  • 1 - 2 - 4 - 3 - 5
  • 2 - 4 - 1 - 5 - 3
Q.21

Which of the following conditions should be satisfied to call an astable multivibrator circuit using discrete components as a digital circuit?

  1. A flip-flop is always a digital circuit.
  2. Only when we assign 1 and 0 to the high and low levels of the output, a flip-flop is called a digital circuit.
  3. Only if the power, supply voltage is maintained at + 5 V or - 5 V, it is called a digital circuit.
  4. Only if it is in IC form, following the technology of IC manufacture, it is called a digital circuit.
Select the correct answer from the codes given below:
  • 1 only
  • 2 and 3
  • 2 only
  • 3 and 4
Q.22

With regard to a transmission line, which of the following statements is correct?

  • Any impedance repeats itself every 1/4 on the Smith chart.
  • The S.W.R. = 2 circle and the magnitude of reflection coefficient = 0.5 circle coincide on the Smith chart.
  • At any point on a transmission line, the current reflection coefficient is the reciprocal of the voltage reflection coefficient.
  • Matching eliminates the reflected wave between the source and the matching device location.
Q.23

Which of the following antenna is obtained by modifying a waveguide?

  • Microstrip Antenna
  • Helical Antenna
  • Horn Antenna
  • Dipole Antenna
Q.24

What is the minimum value of VSWR that may exist on a transmission line?

  • Less than zero
  • Zero
  • One
  • 10
Q.25

Assertion (A): For same drain current rating N-channel MOSFET occupies more area than p-channel MOSFET.

Reason (R): Electron mobility is much higher than hole mobility.

  • Both A and R are individually true and R is the correct explanation of A
  • Both A and R are individually true but R is not the correct explanation of A
  • A is true but R is false
  • A is false but R is true
Q.26

A memory system of sizeK bytes is required to be designed using memory chips havingaddress lines and 4 data lines-each. The number of such chips required to design and the memory system is :

  • 2
  • 4
  • 8
  • 16
Q.27

The antenna most commonly used for TV broadcasting in the UHF band is

  • turnstile antenna
  • dipole antenna
  • yagi antenna
  • rhombic antenna
Q.28

In a uniformly doped BJT, assume that NE, NB and NC are the emitter, base and collector dopings in atoms/cm3, respectively. If the emitter injection efficiency of the BJT is close unity, which one of the following conditions is TRUE?

  • NE = NB = NC
  • NE >> NB and NB > NC
  • NE = NB and NB < NC
  • NE < NB < NC
Q.29

Consider the following statements about ultrasonic flow meters:

  1. The measurement in insensitive to viscosity, pressure and temperature variations.
  2. It has bidirectional measuring capability and can be used for any pipe size.
  3. It has a relatively lower cost.
  4. It has good accuracy, fast response and wide frequency range.
Which of the above statements is/are correct?
  • 1 only
  • 1 and 2 only
  • 1, 2 and 4
  • 3 and 4 only
Q.30

Which of the following materials in not an insulator?

  • Diamond
  • Graphite
  • Bakelite
  • Lucite
Q.31

Ferromagnetic materials show hysteresis in B - H characteristic. As the magnetic field in increased slowly from zero value, what is the first process which sets the material to give net magnetization?

  • Growth of favourably oriented domains at the cost of other domains by reversible boundary displacements
  • Growth of favourably oriented domains at the cost of other domains by irreversible boundary displacements
  • Domain wall orientation
  • A combination of processes (a) and (c) above
Q.32

Which of the following is a microwave source with a 'cross-field' structure?

  • Double cavity klystron
  • Reflex klystron
  • Magnetron
  • Travelling wave tube
Q.33

Consider the following statements regarding sources or error in a Q-meter:

  1. If a coil with resistance R is connected in direct measurement mode and if the residual resistance of Q-meter is 0.1 R, then the measure Q of the coil would be 1.1 times the actual Q.
  2. If the inductance to be measured is less than 0.1 mH, the error due to presence of residual inductance cannot be neglected.
  3. The presence of distributed capacitance in a coil modifies the effective Q of the coil.
Which of the above statements are correct?
  • 1, 2 and 3
  • 1 and 2 only
  • 2 and 3 only
  • 1 and 3 only
Q.34

An amplitude modulated signal occupies a frequency range fromkHz tokHz. If can be demodulated by which of the following?

  • Using an envelope detector and filter
  • Multiplying with a 395 kHz local signal
  • Multiplying with a 405 kHz local signal
  • Low pass filtering with cut off at 400 kHz
Q.35

Which of the following does not apply to Yagi-Uda antenna

  • High gain
  • Reasonably good bandwidth
  • Folded dipole
  • Parasitic elements
Q.36

Which of the following quantities cannot be measured/determined using Hall effect?

  • Type of semiconductor (p or n)
  • Mobility of charge carriers
  • Diffusion constant
  • Carrier concentration
Q.37

Which one of the following pairs is not correctly matched?

  • NaCl : Diamagnetic
  • Gd : Paramagnetic
  • Ferrite : Ferrimagnetic
  • Cr2 O3 : Ferromagnetic
Q.38

What does a link budget for satellite communication include?

  • Total cost of satellite
  • Cost of satellite plus launch vehicle
  • Signal and noise levels is dB
  • Margins of error permitted
Q.39

Which one of the following materials is used for making permanent magnets?

  • Steel
  • Carbon
  • Carbon-Steel
  • Graphite
Q.40

What happens when a paramagnetic material is heated above Curie temperature?

  • It becomes diamagnetic
  • It becomes nonmagnetic
  • It becomes ferromagnetic
  • It becomes anti-ferromagnetic
Q.41

The number of essential prime implicant for the logic expression
F = ABC + C D A + CDA + ABC + BD

  • 3
  • 5
  • 4
  • 6
Q.42

How many roots with positive real parts do the equation s3 + s2 - s + 1 = 0 have?

  • Zero
  • One
  • Two
  • Three
Q.43

Which one of the following pairs is not correctly matched?

  • NaCl : Diamagnetic
  • Gd : Paramagnetic
  • Ferrite : Ferrimagnetic
  • Cr2 O3 : Ferromagnetic
Q.44

Which of the following conditions should be satisfied to call an astable multivibrator circuit using discrete components as a digital circuit?

  1. A flip-flop is always a digital circuit.
  2. Only when we assign 1 and 0 to the high and low levels of the output, a flip-flop is called a digital circuit.
  3. Only if the power, supply voltage is maintained at + 5 V or - 5 V, it is called a digital circuit.
  4. Only if it is in IC form, following the technology of IC manufacture, it is called a digital circuit.
Select the correct answer from the codes given below:
  • 1 only
  • 2 and 3
  • 2 only
  • 3 and 4
Q.45

Period of the signal is:

  • 8
  • 1
  • 24
  • 16
Q.46

Which of the following materials in not an insulator?

  • Diamond
  • Graphite
  • Bakelite
  • Lucite
Q.47

Consider the following statements regarding sources or error in a Q-meter:

  1. If a coil with resistance R is connected in direct measurement mode and if the residual resistance of Q-meter is 0.1 R, then the measure Q of the coil would be 1.1 times the actual Q.
  2. If the inductance to be measured is less than 0.1 mH, the error due to presence of residual inductance cannot be neglected.
  3. The presence of distributed capacitance in a coil modifies the effective Q of the coil.
Which of the above statements are correct?
  • 1, 2 and 3
  • 1 and 2 only
  • 2 and 3 only
  • 1 and 3 only
Q.48

Which of the following does not apply to Yagi-Uda antenna

  • High gain
  • Reasonably good bandwidth
  • Folded dipole
  • Parasitic elements
Q.49

How many roots with positive real parts do the equation s3 + s2 - s + 1 = 0 have?

  • Zero
  • One
  • Two
  • Three
Q.50

The number of essential prime implicant for the logic expression
F = ABC + C D A + CDA + ABC + BD

  • 3
  • 5
  • 4
  • 6
0 h : 0 m : 1 s