The document is a test booklet for an Electronics and Communication Engineering exam. It contains instructions for the exam, which will last 2 hours and contain 120 multiple choice questions. Candidates are instructed to answer all questions on the provided OMR answer sheet using a blue or black ballpoint pen. Calculators, phones and other electronic devices are not allowed. The booklet contains 16 pages and candidates should not detach any pages.

1. A
S
E
T
E C - 16
Booklet No. :
Electronics & Communication Engineering
Duration o
f Test : 2 Hours Max. Marks: 120
raa [ [ [ [ [ [ [ [ ]
N p @ p t t h t ti i (i t € _
Date of E x a m i n a t i o n ; 0 M R Answer Sheet No.;
Signature of the Candidate
INSTRUCTIONS
Signature of the Invigilator
I . This Question Booklet consists o
f 120 multiple choice objective type questions t
o be answered
in 120 minutes.
2. Every question in this booklet has 4 choices marked (A),(B), (C) and (D) f
o
r its answer.
3. Each question carries one mark. There are no negative marks f
o
r wrong answers.
4. This Booklet consists of 16 pages. Any discrepancy or any defect is found, the same may be
informed t
o the Invigilator f
o
r replacement o
f Booklet.
5. Answer all the questions on the OMR Answer Sheet using Blue/Black ball point p
e
n only,
6. Before answering the questions on the OMR Answer Sheet, please read the instructions printed
o
n the OMR sheet carefully.
7. OMR Answer Sheet should be handed over to the Invigilator before leaving the Examination
Hall.
8. Calculators, Pagers, Mobile Phones, etc., a
r
e not allowed into the Examination Hall
9. No part o
f the Booklet should be detached under any circumstances.
10. Th
e seal o
f the Booklet should be opened only after signal/bell is given.
EC-16-A I I I l l ll
ll I
I I II I I I

2. ELECTRONICS & COMMUNICATION ENGINEERING (EC
1 1 3
I. The sum of the eigen values of the matrix A = 0 2 i
s equal t
o
-4 4 3
(A) 6 (B) 8 (c 0 (
D
)
-1 0
2. If the rank of the matrix A = 0 2 -- I is 2then t =
-4 4 3
(A) 1 (B) 8 (C) 0 (D) 2/5
3. The function f(x,y)= + + 6 x + 1 2 has minimum value at the point
(A) (-3,0) (B) (3,0) (€) (0,1 (D) (1 , 1 )
4.
a/ 2'f
[f r = - s =
a ' a
x
@
(A)
(C)
a , _ L e e n at the saddle point the function f(x,) satisfy
y
•
(D) s t - r > 0
5. If f(z) i
s analytic within and on a closed curve C and a is any point within C then the
re.} 4 4 . where k is eual to
' . - a
( A )
"
()
1
er
«c
1 •
I
Vi
(D) 2ni
6. A random variable X has probability density function f(x) =ke ,0 then k =
(A) (B) (C) 2 (D)
1
2
7. If the coefficient of correlation i
s 0.98, then the variables are
(A) Negatively correlated (B) Weak positively correlated
(C) Strong positively correlated (D) Uncorrelated
8. The order of the differential equation (tx)
2
+ Sy}= x is
(A) 1
s«[El
(B) 6 (C) 2
2
(D) 1/3
E
C

3. 9.
• 6
An integrating factor of xy +y=x'y
(A) e)° (C)
x
(D) r
10. Which one of the following i
s a series method ?
(A) Picards Method (B) Euler method
(C) Milne Method (D) Runge Kuta Method
II. The impulse response of an LTI system i
s given b
y h[n] = 26[n -- 20]. Determine the
output y[n] if the input i
s x[n] = n.
(A) ( -- 2 0 ) ° (B) 26[? - 2 0 ] (C) 2( - 20) (D) 26[( - 20)]
12. The input output relationship of a system is given b
y y[n] = cos [x(n)]. The system is
(A) linear and invertible (B) linear and non-invertible
(C) non-linear and invertible (D) non-linear and non-invertible
y(o)= 2xt/5)
y(t) = 2x(2t/5)
(B)
(D)
The Fourier series coefficients of a periodic signal x(t) with time period T are• Find the
signal y(t) whose Fourier series coefficients are given by = 2X, and time period is
T/5.
(A) y ( t ) = 2x(5t)
(C) y ( 0 ) = x(10t)
13.
14. Choose the f
a
l
se statement.
(A) n6() = 0
(c 6G) = :.,u0)
0B) u() = :. _80
(D) n6( - 2 ) = 4 6 ( - 2)
15. The signals x,(t) and x(0) are both band-limited t
o (-u,+@,) and (-@, +@)
respectively. The Nyquist sampling rate for the signal x,(t)x(t) will b
e
(A) 2a, if @
, > @
2 (B) 2@ if @, < @
(C) 2(6, + @a) (D)
16. The response of an LTI discrete-time system t
o a periodic input with period N i
s
(A) not periodic. (B) periodic having a period N.
(C) periodic having a period 2N. (D) periodic having a period N/2.
17. The step response of an LTI system whose impulse response h() = u() is
(A) (n + l)u(n) (B) nu(n)
(C) (n - 1u() () nu(n)
18. If the Fourier series coefficients o
f a signal a
r
e periodic, then the signal must be
(A) continuous-time, periodic. (B) discrete-time, periodic.
(C) continuous-time, non-periodic. (D) discrete-time, non-periodic.
s e - [I] 3 Ec

4. (B) X
_ ( O X,
2
The Fourier transform of the exponential signal eio! j
g
(A) a constant (B) a rectangular pulse
(C) a
n impulse (D) a series of impulses
Let represent the discrete-time Fourier series (DTFS) coefficients of the periodic
sequence x() with period N. The DTFS coefficients o
f the signal (-1)x() in terms of
are
(A) X
20.
19.
21. The frequency response of a system with h(n) = () - ( 1) is given b
y
(A) ~(@) - ~ ( - 1 ) (B) 1 - el
(C) u(@) - u ( @ - 1 ) (D) 1 - e l
22. The ROC of a causal finite-duration discrete-time signal is
(A) the entire z-plane except z = 0
(C) the entire z-plane
(B) the entire z-plane except z = oo
(D) a ring in the z-plane
23. Linear phase systems have a constant
(A) phase
(C) magnitude
(B) group delay
(D) phase and magnitude
24. In an N-point D
FT of a finite duration signal x(n) of length L, the value of N should b
e
(A) N > L (B) N = 0 (C) N < L (D) N = L
2
F
T algorithm
Chirp transform algorithm
(B)
(D)
The algorithm used to compute any set of equally spaced samples of Fourier transform on
the unit circle is
(A) DFT algorithm
(C) Goertzel algorithm
25.
N
N log
2
N log N
(A)
Total number of complex multiplications required in radix -
2 DIT.FT algorithm is
N
(B) ;; log,N
N N
(
) ; log
(c
26.
27, The steady-state error of a feedback control system with an acceleration input becomes
finite in a
(A) type O system (B) type I system
(C) type 2 system (D) type 3 system
K(s+5)
28. Considering the root locus diagram fo
r a system with G(s) =- 7
, »)(s n( i, , t h e
s s + 2 s + 4 ) ( $ +2$+2)
meeting point of the asymptotes o
n the real axis occurs a
t
(A) - 1 . 2 (B) -0.85 (C) -1.05 (D) -0.75
sec-[] 4 E
C

5. 29.
8(s+3)
If for a control system, the Laplace transform of error e(t) i
s given a
s ' t h e n the
s(s+10)
steady state value of the error works out a
s
(A) 3.6 (B) 1.8 (C 3.2 (D) 2.4
30. The equation
s--plane.
(A) one (B) two (C) three
roots in the le
f
t halt ot
(D) four
2s + s + 3 s 4+ 5 s + 1 0 = 0 has
31. Given a unity feedback control system with G(s) = , t h e value of K f
o
r a damping
s(s+4)
ratio of 0.5 is
(A) I ( 1 6 (
c 3
2 (D) 64
32. The input t
o a controller is
(A) sensed signal (B) desired variable value
«c error signal (D) servo-signal
33.
34.
If the Nyquist plot of the loop transfer function G(s)H(s) of a closed-loop system encloses
the (1, j0) point in the G(s)H(s) plane, the gain margin of the system is
(A) zero (B) greater than zero
(C) less than zero (D) infinity
The transfer function of a phase-lead controller is given b
y
(A)
(c
i+@Ts > 1. T > 0
I+Ts '
-aTS > 1. T > 0
1 + T s ' +
(8)
(D)
aT> < 1 , T > 0
1 + 7 s '
-aTS < 1 T > 0
1+7¢ ' '
35, A system with gain margin close to unity or a phase m
a
r
g
i
n close t
o zero is
(A) highly stable (B) oscillatory
(C) relatively stable (D) unstable
36. Peak overshoot of step-input response of an underdamped second-order system 1
s
explicitly indicative of
(A) settling time (B) rise time
(C natural frequency (D) damping ratio
37. If the system matrix of a linear time invariant continuous system is given by
A = [ " , _',]. i
s characteristic equation is given by
(A) s? 4 5 5 + 3 = 0 (B) s? - 3 s - 5 = 0
( C ) s? 4 3 s + 5 = 0 (D) s? + 2 s + 2 = 0
sec-[] s E
c

6. 38. A phase lag-lead network shifts the phase of a control signal in order that the phase of the
output
(A) lags a
t low frequencies and leads at high frequencies relative to input
(B) leads a
t low frequencies and lags at high frequencies relative t
o input
(C) lags at all frequencies relative to input
(D) leads a
t all frequencies relative t
o input
39, The Bode plot of the transfer function G(s) = s is
(A) constant magnitude and constant phase shift angle
(B) -20 dB/decade and constant phase shift a
n
g
l
e
(C) 2
0 dB/decade and phase shift of n/2
(D) zero magnitude and phase shift
. -
40, The state-variable description of a lincar autonomous system is X = AX, where X is a two­
dimensional state vector and A is a matrix given b
y A = [� i1- The poles of the system
are located at
(A) -
2 and +
2
(C) -2and -
2
41. 2
4 voice channels (
4 KHz bandwidth) are sampled a
t 8 times the Nyquist rate and
multiplexed. Each voice channel is delta modulated. I bit is added per frame for
transmitting control information. What i
s the data rate of transmission ?
(A) 1.600 Mbps (B) 1.544 Mbps
(C) 2.048 Mbps (D) 1536 Mbps
42, The characteristic of the channel resembles the filter shown in the figure I . Find the time
delay of the channel.
R
• •
C
Figure I
(A) ± o [ , 4 ) (B) + [ , 4 )
2
m 2RC 2RC
(C) 'an'(2nRC (D) 2n tan'(27RC
2rm
43. Let X be a continuous random variable with uniform PDF defined by f, ( x ) - ' , f o r
2r
0 < x < 2 n and zero elsewhere. Find 0
,
"
n 7 7
(A)
3
(B)
6
(
C)
6
(D)
%
s«[El 6 E
C
(B) -2j and +2j
(D) +2and +2

7. 44. The stationary process has
(A) ensemble average equal t
o time average
(B) all the statistical properties dependent on time
(C) all the statistical properties independent of time
(D) zero mean and zero variance
45. In a modulator, i
t i
s found that the amplitude spectrum of the signal a
t the output of the
modulator consists of a component f,, the carrier frequency and one component each at
f + f andf, f where [% i
s the modulating signal frequency. The modulator used is
(A) SSB (B) PAM (C) PCM (D) A
M
46. A signal X(t) = 4 c o s 2 n f t + 2 c o s 4 n f. t + mt) cos2nft is applied to the system
shown i
n Figure 2. What will b
e Y(t)?
X(tl---•-<r
I 0 w p a s
f i l t e r
]
(A) 4m(t) cos 4nf,t
(C) 4 + m(t)
2Cos2r f
e t
Figure 2
(B) 4cos4nft
(D) 4m(t)
47. The power of an FM modulated signal with modulation index ~ and carrier c(t) =
A cos2nf,t is
+
(A) (B) e ( ±)
] 4
2 2
2
6» +(+)
48.
49.
If a Gaussian process X(t) is applied to the stable linear filter, then the random process
developed at the output of the filter will be
(A) Uniform (B)
(C) Gaussian (D)
Binary data i
s transmitted using PSK signaling scheme withS,(t) = ACos@_t,
S,(t)=-ACos@t, 0 t< T
, where bit duration T is equal to 0.2 ns. The carrier frequency
is f, = 5 f , . The carrier amplitude at the receiver input is I V and the power spectral
density of the AWGN at the input i
s 10'' W/Hz. The probability of error f
o
r the optimum
filter will be
Exponential
Rayleigh
(A) erfe(5.5)
s«[El
(B) 0.5erfe(5) (€) 0.5ere(/5) (
) erte([5.5
7 E
C

8. so. Which of the following is incorrect?
(A) H(y/x) = HU,y)-HK)
(C) HU,y) =HCl y
) +H(y)
(B) I(x,y)= HG)-H(/x)
(D) I(x,y)= H()-H(/x)
51.
52.
53.
54.
55.
56.
The SSB-SC is used for the following application:
(A) Radio Broadcasting (B) Point to point communication
(C) Telegraphy and Telephony (D) TV transmitter
What does a logic 1 Delta Modulation (
D
M
) bit indicate ?
(A) The message signal's amplitude i
s decreasing.
(B) The feedback signal's amplitude is greater than the message signal's amplitude.
(C) The feedback signal's amplitude is constant.
(D) The feedback signal's amplitude is less than the message signal's amplitude.
The asymptotic value or±? required to achieve the data rate equal to the channel
N
%
capacity when the channel bandwidth tends t
o infinity is equal to
(A) 1.6 d
B () -3dB (C) 0 d (D) infinite
The golden rule f
o
r encoding messages with unequal probabilities is to
(A) Encode a message with high probability by a longer code word.
(B) Encode all messages with equal length code.
(C) Encode a message with high probability b
y a shorter code word.
(D) Encode a message b
y arbitrary choosing variable length codes.
The output Signal to Noise Ratio, (SNR), of matched filter depends only on
(A) ratio of input noise to output noise.
(B) ratio of output noise to power spectral density of white noise at input.
(C) ratio of signal energy to power spectral density of white noise a
t input.
(D) correlation of input signal to output signal.
In multiple access i
s achieved b
y allocating different time slots f
o
r
the different users.
(A) TDMA (B) CDMA (C) FDMA (D) FGM A
57. Cellular CDMA system uses what modulation method ?
(A) GF
S
K (B) ASK (C) QAM (D) BPSK
58. The only one signal waveform that produces zero inter symbol interference (1SI) i
s
(A) sin(2B0) (B) cos(2BD) (C) sine(2Bat) (D) sin(Bao)
59. The length of antenna depends on
(A) wavelength of radiation
(C) angle of radiation
(B) current distribution
(D) area o
f cross-section
s«[El 8 E
C

9. 60. For a broad side linear array which of the following is not correct ?
(A) The maximumradiation occurs perpendicular to the line of the array a
t d = 90,
(B) The progressive phase shift (c) between elements is zero.
(C) Width of principal lobe is less than that of an end fire array.
(D) The maximum radiation occurs along the line of array at d = 0°
61. The phase velocity of waves propagating in a hollow metal waveguide is
(A) greater than the velocity of light in f
r
e
e space
(B) less than the velocity of light in free space
(C) equal to the velocity of light in f
r
e
e space
(D) equal t
o the group velocity
62. If the diameter of a 2/2 dipole antenna is increased f
r
o
m A/100 to 2/50 then its
(A) bandwidth increases (B) bandwidth decreases
(C) gain increases (D) gain decreases
63, The directive gain cannot be stated as
(A) the ratio of the radiation intensity i
n that direction to the average radiated power
(8) the function of angles
(C) the directivity of a
n antenna when directive gain is maximum
(D) independent of angles
64. An electromagnetic wave has electric field component along Y-direction and magnetic
field component along X-direction. The electromagnetic wave is propagating along
(A) Z -direction (8) X-direction
(C) Y-direction (D) XY -direction
65. The lower cut-off frequency of a
(3 x4.5 em) operating at IO GHz is
(A) 10 GHz (B) 9 GHz (C) "" GHz
9
(D) 1°GHz
3
rectangular wave guide with inside dimensions
66.
67.
During night which layer does not exist?
(A) Dlayer (B) F, layer (C) F
, layer
The dominant mode of rectangular waveguide is
(A) TE, (B) TM, (C) TE%
(D) E layer
(D) TE%
68. Vector potential is a vector
(A) whose curl is equal to the magnetic flux density
(B) whose curl is equal to the electric field intensity
(C) whose divergence is equal to the electric potential
(D) which is equal t
o the vector product E
H
set[] s E
C

10. 69, A uniform plane wave in air is incident normally on an infinitely thick slab. If the
refractive index of the glass slab is 1.5, then the percentage of the incident power that i
s
reflected from the air-glass interface is
e
(A ) 0
% (B) 4
% (C) 2
0
% (
D
) 10%
70, In an impedance Smith chart, a clockwise movement along a constant resistance circle
gives rise t
o
(A) a decrease in the value of reactance
(B) a
n increase in the value of reactance
(C) no change in the reactance value
(D) no change in the impedance value
v
,
r
The value of "Z," for the circuit shown below.
l
71.
(A) 4/9 Ohms
(C) 4/1 I Ohms
(B) 1 H / 4 Ohms
(D) 9
/
4 Ohms
72. Two voltage sources, connected in parallel as shown in the below figure, must satisfy the
conditions
v,
-
�
-
---<
/ +
r
I
r
2
(A) v; #v» but r; = r
2
(C) vy=vandr=r
(B) v=vandr#r
(D) r#0or r/0if v,#v
73. Acomposite voltage V = 10 sin100t + 10 cos IO0t is applied across a series combination of
a capacitor of I f and resistance of 2
0 KQ. The average power dissipation in the resistance
1s
(A) 5mW (B) 3.5mW (C) 2.5mW (D) 1.25mW
'
.. . . . · ,z (e $ + 2 s + 2 ~
74. The driving point impedance function s = can be realized
s + s+ 1
(A) R-C Network (B) R-L Network
(C) L-C Network (D) R-L-C Network
s « - [El 10 EC

11. 75, A 100Q, I W resistor and 8
00
0
2
, 2W resistor are connected in series. The maximum DC
voltage that c
an be applied continuously t
o the series circuit without exceeding the power
limit of any of the resistors i
s
(A) 90 V (B) 5 0 V (C) 45 V (D) 40 V
V
I,O'A
The Thevenin's equivalent circuit t
o the left of AB i
n figure shown has ,,is given by
10
76.
(A) 1/3 Ohms
a . r a
'---------'---,I -on
(B) 3/2 Ohms (C) I Ohms (D) 1/2 Ohms
77. Under steady state condition
(A) Inductor acts a
s short an
d Capacitor acts a
s open
(B) Inductor acts a
s open and Capacitor acts as open
(C) Induetor acts a
s open and Capacitor acts a
s short
(D) Inductor acts a
s short and Capacitor acts as short
(B) unity, 0
(D) 0
, unity
78. In the series R
L
C circuit, the power factor of the circuit a
t f = f
, (Lower Frequency) and
f=f(resonance frequency)
(A) 0.707(ag), unity
(C) 0.707(cad), unity
(D) 4mH
(C) 2mH
79. Two coils are connected in series with inductance values of 16mH and 8mH.The value of
mutual inductance is
(A) 12mH (B) 8mH
80. In parallel RL
C circuit, if L=8H a
n
d C=2F then the value of critical resistance is
(A) 0.5 Ohms (B) I Ohm (C) 2 Ohms (D) 3 Ohms
81. The transient fr
e
e condition in R
L and RC circuits with AC excitation will not depend on
(A) Source frequency
(B) Initial phase of the excitation
(C) Maximum values of the excitation(Voltage a
n
d C
u
r
r
e
n
t
)
(D) Circuit constants(R,L, C)
82. A Unit impulse voltage i
s applied t
o one po
rt network, which has two linear components.
If the current through the network i
s 0 f
o
r 1<0 and decays exponentially f
o
r z>0 then the
network consists of
(A) Resistor and Inductor in series (B) Resistor a
n
d Inductor in parallel
(C) Resistor a
n
d Capacitor in parallel (D) Resistor a
n
d Capacitor i
n series
s«[El 11 E
C

12. 83. A graph of network has 4 nodes and 7 branches. The number o
f links(l), with respect t
o the
chosen tree, would b
e
(A) 2 (JJ) 3 (C) 4 (D
) 5
VP1 ± VP2
( P I ± P2
(B)
(D)
A network consists of a large number of ideal linear resistors (R) in series with two
constant ideal sources. Power consumed b
y R is PI when only the first source is active and
P
2 when only the second source is active. If both sources are active simultaneously, the
power consumed b
y R is
(A) Pl + P 2
(c) 6PI ± VP2
84.
85. Choose the logic gate family which is having minimum propagation delay
(A) TT
L (B) MOS (C) DTL (D) ECL
86. An 8085 microprocessor based system uses a 4K x 8 bit R
A
M with a starting address of
AA00 H. The address of the last byte in this RAM is
(A) OFFF H (B) I 0 0 0 H (C) B9FF H (D) BA0O H
87. How many memory IC's of capacity 2K x 4 are required to construct a memory capacity
of 1 5 K x 8 ?
(A) 14 (B) 15 (C) 16 (D) 1 8
88. The present output Q
, of an edge triggered JK flip-flop i
s logic I . If k=1 then Q
,
(A) cannot be determined
(C) will be logic ' I '
(B) will be logic '0'
(D) will be race around
(D) 7.88 V
89. A 12-bit (3-digit) DAC that uses the BCD input code has a full scale output of 9
.
9
9 V. The
value of V,for an input of 0 1 1 0 1001 0101 is
(A) 4 . 1 1 V (B) 6.95 V (C) 7.38 V
90. The starting address of below program is 0100 H
LXISP, OOFF H
L
X
I H, 0701 H
M V I M , 2
0 H
MVI A. 2
0 H
S U B M
The content of accu mul ator when the program counter rcaches 010B H is
(A) 2
0 H (B) 0 2 H (
C
) 00 H (D) F
F H
91. A I micro-second pulse can be converted into a I milli-second pulse b
y using
(A) A Mono-stable multi-vibrator (B) An Astable multi-vibrator
(C) A Bi-stable multi-vibrator (D) A JK flip-flop
s«[El 12 E
C

13. 92. What i
s the maximum frequency with which a 4-bit binary ripple counter can work, if the
propagation delay from CLK to Q of each flip-flop is 2
4 ns?
(A) 100 MH
z (B) 96 MH
z
(C) 10.4 MH
z (D) 6.9 MHz
93. The Boolean function/(wax,y,z) = )m(5,7,9,11,13,15) i
s independent of variables
(A) w (B) r (C) y (D) za n d r
94. The initial sequence of 4-bit Johnson counter is I H I 0 , what will be the sequence after third
clock pulse
(A) 1000 (B) 0001 (C) 1 H 1 0 (D) 0 0 1 1
95, The logic function (A+B)(A' +B') can be implemented b
y giving the inputs A and B t
o a
I W
O input
(A) NOR gate
(C) EX-NOR gate
(B) NAND gate
(D) EX-OR g
a
t
e
96. The function /(A,B,C,D) = )m(0,1,4,6,7,8,10,14,15), the number o
f prime implicants and
essential prime implicants are
(A) 6 , 1 08) 6,2 (C) 7 , 1 (D) 7 , 2
0 1 0 1 , 0 1 0 1
0 1 0 1 , 0100
(B)
(D)
A 4.6 V i
s given a
s input t
o the counter type ADC and SAR type ADC then the digital
output produced respectively
(A) 0100, 0100
(C) 0100, 0 1 0 1
97.
98. The current gain of a BJT drops at high frequencies because of
(A) Junction capacitances (B) Bypass capacitances
(C) Coupling capacitances (D) Parasitic capacitances
Alloying
[on-implantation
(B)
(D)
Which of the following fabrication i
s suitable fo
r maintaining the PN junction a
r
e
a t
o the
required accuracy?
(A) Grown junction type
(C) Diffusion
99.
JOO. Moore's law relates t
o
(A) Speed of operation of bipolar devices
(B) Speed of operation of MOS devices
(C) Power rating of MOS devices
(D) Level of integration of MOS devices
JOI. The value of transport factor in a BJT is effected by
(A) Doping of emitter (B) Width of collector
(C) Doping of base (D) Life time of minority carriers
s«[El 13 E
C

14. 102. T
w
o I O V identical zener diodes ar
e connected back t
o back, the maximum voltage drop
across the diodes when they are conducting is
(A) 2
0 V (B) 10 V (C) 10.6 V (D
) 9. 4 V
103. A P
N junction exhibits a transition capacitive effect of several farads i
n reverse
bias, but m
a
y have many farads of diffusion capacitance in the forward biased state.
(A) micro, pico (B) pico, micro (C) milli, milli (D) milli, micro
104. An amplifier has R,= 2 KO and R,= 40 KQ and A, = 9
0. The amplifier is modified t
o
20K and 4K
0.2K and 4
0
0
K
(B)
(D)
provide 10% negative voltage feedback in series with input. The values of R
, and R
,
respectively are(in ohms)
(
A
) 2
K and 4
0
K
(C) 16K and 5K
(D
) 2
0
(C) 5
0
(B) 10
105. Class-A power amplifier delivers 10W to a load with input signal power of 200mW. The
power gam 1s
(A) 2
00
1116. Transistor has h
(A) -50
= 50, its h
, =
(B) 50 (C) -51 (D) 5
107. A cascade amplifier has higher cut off frequency
(A) Equal to that of single stage amplifier
(B) Less than that of single stage amplifier
(C) More than that of single stage amplifier
(D) Becomes double
108. An ideal current controlled voltage source has
(A) R, is infinity, , is zero (B) R, is zero, R, is infinity
(C) R,i s zero,, i
s zero (
D
) R,is infinity, R, is zero
109. The current density of electrons through any conductor carrying current is given by
2 2 5
(A)
. n e , "" (B) . _ 11e, E (
C
) . ne , (D) . n·er ,.
.
J = £ ho- J- . J= - E
m m m
E n
(D
)
1
1 +a
(
C
)
1 + 3
(B)
In BIT, Sensitivity of 3 (common emitter current gain) with respect to a (common base
current gain) is
1
(A)
1 + /J
110.
Ill. A differential amplifier has a differential gain of 2
0000 and CMRR = 80dB. Common
mode gain i
s
(A) 2
s«[El
(B) 1 (C) 0.5
14
(D) 0
E
C

15. 112, Which of the following h-parameters relations i
s incorrect ?
(A) h
, = h , (B) h , = I -- h ,
(c) h
, = I + h , (
) h , = h ,
113. Which of the following i
s true for n type semiconductor ?
(A) n = N y + p (B) N + n = p
(C) n + p = N , (D) N , + n = p
114. If 10 V is the peak voltage across the secondary of the transformer in a half wave rectifier
with capacitive filter, peak inverse voltage of the diode will be
(A) 20V (B) 1 4. 1 4 V (C) I 0 V (D)7.8 V
115, The condition of sustained oscillation in BIT phase shift oscillator i
s given by
(where k _ '
- «Rd R
, i
s collector resistance)
R
(A)
(C)
2
9
h
e
> 23+ +4K
4
h
> 23+; +29K
(B)
(D)
2
3
h
> 29+ +4K
4
h
> 29+z +23K
116. A CE amplifier has R, =1000 Q an
d R
, = 100 Q and h,=99,h, =1000 9; the input
resistance , is given approximately b
y
(A) 1 00 0 (B) 1 0 K 0 (C) 1000 9
117, When a
n electron moves through a potential difference of I0 V, the energy acquired by it
will be
(D
) 1 1 K O
(A) 10 joules
(C) 1.6x 10 "ev
(B) 1 6 1 0 " e v
(D) JO eY
118, Which of the following represents the Cascade configuration?
(A) C E - C E 0) CE--CB (C) CC-CC (D) CE-CC
119. Condition for the minimum conductivity for the semiconductor
» a - ~ [ c» « - ~ «e a - n ! «o»
V, ta.
,
n = ,
,
120, The scaling factor of an MOS device is a using constant voltage scaling model, the gate
area of the device will be scaled by
(A) /
a (B) 1/ (C) M e (D) I / a '
s«[El JS E
C

16. s«[El
SPACE FOR ROUGH WORK
16 E
C

17. Electronics and Communication Engineering (EC)
SET-A
Question N
o Answer Question N
o Answer
1 A 61 A
2 D 62 C
3 A 6
3 D
4 A 6
4 A
5 D 6
5 D
6 8 66 A
7 C 67 D
8 A 6
8 A
9 D 6
9 B
10 A 7
0 8
11 C 71 C
12 D 72 D
13 A 7
3 B
14 C 7
4 A
15 C 75 C
16 8 7
6 D
17 A 77 A
18 8 7
8 C
19 D 7
9 C
20 C 8
0 8
21 D 81 C
22 A 82 A
23 B 83 C
24 A 8
4 C
25 A 85 D
26 B 8
6 C
27 C 87 C
28 D 8
8 B
29 D 8
9 8
30 B 9
0 C
31 B 91 A
32 C 92 C
33 C 9
3 C
34 A 9
4 D
35 C 95 B
36 D 9
6 D
37 A 97 D
38 A 9
8 A
39 C 9
9 C
40 A 100 D

18. 41 A 101 C
42 C 102 C
43 C 103 B
44 C 104 B
45 D 105 D
46 C 106 C
47 A 107 H
48 C 108 C
49 C 109 A
so B 11 0 B
51 B 111 A
52 D 112 C
53 A 113 A
54 C 114 A
55 C 115 A
56 A 11 6 D
57 D 117 I)
58 C 118 B
59 B 119 B
60 D 120 B