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Q.1.When a large number of analog signalsis to be converted to digital form, an analog multiplex

or is used. The A to D converter suitable in this case will be ..

dual slope type

up down counter type

Successive approximation type

forward counter type

Q.2 .In the formation of Routh's array the situation of a row of zeros indicates that the system-

has symmetrically located roots

is not sensitive to variationsin gain

is stable

is unstable

Q.3 Mark out wrong statement. Modulationis used to-

Reduce the bandwidth used

Separate differing transmissions

Ensure that intelligence may be transmitted over long distances

Allow the use of practicable antennas

Q.4.Mark out a wrong statement for two phase servo motor-

The rotor diameter is small

The rotor resistance is low

The applied voltagesare seldom balanced

The torque speed characteristic is linear.

Q.5.The frequencydeviation in phase modulation is-

independent of the modulatingsignal frequency

inversely proportional to the modulating signal frequency

directly proportional to the modulating signal frequency.


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inversely proportional to the square root of the modulating frequency.

Q.6.Which power amplifiershas maximum efficiency?

Class A

Class AB

Class B

Class C

Q.7.Negative resistance characteristics for its operation is used by .....

TWT

Klystron

Magnetron

MASERS

Q.8..Choose the most appropriate word from the options given below to complete the following

sente nce. Comparative ly few rock musicians are willing to laugh at themselve s, although a hint

of .......... can boost sales of video clips very nicely.

self-deprecation

congeniality

cynicism

embarrassment

Q.9.The binaryequivalent of 9.37510 is ......

1001.011 2

1101.101 2

100.011 2

1111.001 2

Q.10.The output signal amplitudes for1's and 0's in an ADM transmission system ....

Fixed and the repetition rate is also fixed

Fixed but the repetition rate is variable


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Variable and the repetition rate is also variable

variable but the repetition rate is fixed

Q.11.For an RC driving point impedance function, the poles and zeros-

should alternate on real axis

should alternate only on the negative real axis

should alternate on the imaginary axis

can lie anywhere on the left half place.

Q.12.Mark out wrong statement regarding compndor-

It compresses the higher amplitude parts of a signal before modulation and expands them back to

normal again after demodulation.

It gives preferential treatment to the weaker parts of the signal

For weaker signals, it gives a poor ratio of signal strength to quantizing error

Weaker signals, transverse more quantum steps than they would do otherwise and so quantizing

error is reduced

Q.13 .Among other equipment a sub marine cable repeater contains .....

A dc power supply and regulator

Filters for the two directions of transmission

Multiplexing and de-multiplexing equipment

Pilot inject and pilot extract equipment

Q.14.In a communication system noice is most likely to affect the signal-

At the transmitter

In the channel

In the information source

At the destination

Q.15.In gunn effect oscillator which mode having lowest operating frequency ....

mode


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Delayed domain mode

Quenched domain mode

LSA mode

Q.16.In Reflex klystron maximum energy transferred to gap by electrons-

eR

ee

el

eR , ee, el

Q.17.The radio waves get absorbed by atmosphere depends -

Their distance from transmitter is long

Wave power is weak

Improper polarization of wave

Frequency of waves

Q.18.8085 mP has no of sets of communication lines-

2

3

4

None

Q.19.The diversity system in Troposcatter links is made use of to-

a.Increase the bandwidth

b.Prevent noise effects

Increase the directivity of the antenna

d.Detect signal in the presence of fading.

Q.20.The plate e fficiency of a class C amplifier is high because-

A resonant circuit is used as load


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The plate current flows when the instantaneous plate voltage is low.

The plate current flows only when grid is driven positive

None of the above

Q.21.The Nyquist plot of G (jw), H (jw) for a closed-loop control system, passes through (-1,j0)

point in the GH-plane. The gain margin o the system in dB is equal to

infinite

greater than zero

less than zero

zero

Q.22. Where is the hole concentration is greatest?

x = 0

x = L/2

x = L

Uniform

Q.23.Where is the electron concentration is greatest?

x = 0

x = L/2

x = L

Uniform

Q.24.In a direct election between two contestants, 4% of the votes cost are declared to be

illegal. One contestant secures 55% of the v alid votes and wins with a majority of 240 votes.

What is the total number of votes cost ?

2455

2400

2500

None of these


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Q.25.There are two groups A and B consisting of 30 and 70 students respe ctively. If the ave rage

weight of group A is 30 kg and that of group B is 70 kg. Find the average weight of all the

students of group A and group B.

58 kg

50 kg

40 kg

12 kg

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