Instructions:
(a)4 marks will be allotted for correct question and 1 will be
deducted for incorrect question. (b)More than
one answer can be correct.
Que.
1
A cascade amplifier stage is equalent to
A
a comman emittor stage followed by a common base stage
B
a comman base stage followed by a common emittor stage
C
a common base stage followed by an emittor follower
D
an emittor follower stage followed by a common base stage
Que.
2
In order to make Q point independent and varitions B in a transistor amplifier,it
is necessary to make
A
R (b)<< B R(c)
B
(D)R < or = B R(c)
C
(D)R(b) < or = B R
D
R(b) < or = B R(c)
Que.
3
Input resistance of a common base transistor ckt is of the order of
A
0The output resistance of a common base transistor ckt is of
the order of
B
50-100 ohm
C
100-150 ohm
D
150-200 ohm
Que.
4
The emitter coupled pair of BJTs gives a linear transfer relation between
the differential output voltage and input voltage only when the magnitude
of V(id) is less alpha times the thermal voltage, where alpha is
A
4
B
3
C
2
D
1
Que.
5
Maximum efficiency of half wave rectifier is
A
33.33%
B
40.6%
C
50%
D
68%
Que.
6
If the input ac is 10Vrms the maximum voltage that will appear across
the diode of a half wave rectifier with a capacitor input filter will
be
A
10v
B
14v
C
20v
D
28v
Que.
7
The three stage cascaded amplifier of identical non-interacting FET common
source stage has all over an voltage gain of 1000 and overall bandwidth
of 25*10^6rad/sec given g(m) =5mA/v the shunt capacitance of each stage
is given by
A
20PF
B
10PF
C
3.2PF
D
1.6PF
Que.
8
When a +ve gate voltage is applied to MOSFET it is said to operate in
A
enhancement mode
B
depletion mode
C
conduction mode
D
none of these
Que.
9
the tunned ckt for good stability should have
A
low C
B
low r
C
high Q
D
low L
Que.
10
by varying which one of the following the RR feedback oscillator are usually
tunned
A
load impedance
B
bras
C
lore
D
none of these
Que.
11
An operational amplifier has a slow rate of 100V/micre sec. for a freq.
of 10mhz the maximum value of the sine wave output voltage will be
A
100v
B
50/(pi)^v
C
10v
D
5v
Que.
12
the number of flipflop required to build a mod-15 counters is
A
4
B
5
C
6
D
7
Que.
13
The maximum overall efficiency of a transformer coupled class A amplifier
is
A
78.5%
B
25%
C
50%
D
85%
Que.
14
In an FET as V(GS) is changed from zero to increasing reverse biased the
value of g(m)
A
increases
B
decreases
C
remain constant
D
falls suddenly to zero
Que.
15
given for an FET g(m) =95mA/v total capacitance =500pf for a voltage
gain of -30 the bandwidth will be
A
100khz
B
630khz
C
3mhz
D
19mhz
Que.
16
for the resonent ckt shows w =10^5,Q=50,R=400 thevalue of C is given by
A
250PF
B
1000PF
C
500PF
D
1.25PF
Que.
17
In a class A amplifierusing a transistor under ideal condition the maximum
ac power delivered is 1 watt the maximum transistor dissipation capability
has to be
A
1watt
B
2watt
C
3watt
D
4watt
Que.
18
two binary signals A and B are compared the output expression when the
two signals are equal is given by
A
ab' +a'b
B
ab + (ab)'
C
(ab)'
D
ab
Que.
19
the most widely used universal gate are
A
OR and AND gates
B
NOR and NAND gates
C
NOR and AND gates
D
NAND and OR gates
Que.
20
the microprocessor contains ROM chip contains?
A
control function
B
airthmatic function
C
instructions to execute data
D
memory function
Que.
21
Carry-look ahead is type ofadder in which
A
inputs to several stages are examined
B
carries are produced simultaneously
C
carries are produced before hand
D
none of these
Que.
22
Logic shift affects
A
odd positions
B
all positions
C
even positions
D
new positions
Que.
23
Programmable logic array uses
A
ROM matrices
B
PROM matrices
C
RAM matrices
D
solo memory
Que.
24
Race condition can be avoided by introducing......... between the flipflop
A
harmonic suppressor
B
deacceleration
C
delay
D
dusting
Que.
25
An amplifier has an open loop gain of 100, an input impadence of 1kohm,and
an output impedance of 100ohm.a feedback network with a feedback
fector of 0.99 is connected to the amplifier in a voltage series
fedback mode the new input and output impedance respectively are
A
10 ohm and 1 ohm
B
10 ohm and 10 kohm
C
100 ohm and 1 ohm
D
100 kohm and 1 kohm
Que.
26
In a twin wire transmisssion line in the air the adjacent voltage maximum
are at 12.5cm and 27.5cm the operating freq. is
A
300mhz
B
1Ghz
C
2Ghz
D
6.28Ghz
Que.
27
The band width of an N stage tunedamplifire with each stage having a
band width of B, is given by
A
B/n
B
B/(sqrt)n
C
B[(sqrt)2^[1/n]-1
D
B/[(sqrt)(/2^[1/n]-1]
Que.
28
the resolution of a 12-bit D/A convertor using a binary ladder with 10v
as the full scale output will be
A
2.44mA
B
3.50mA
C
4.32mA
D
5.12mA
Que.
29
the number of comparetor ckt requires to build a 3-bit simultaneous A/D
convrtor is
A
7
B
8
C
15
D
16
Que.
30
A magnetic drum of 8 inches diameter has 100 tracks and storage density
of 200bits/inches its storage capacity will be
A
502400 bits
B
8402 bits
C
1004800 bits
D
202400 bits
Que.
31
the function of inhabit line in a memory in
A
to write 1 in a core
B
to read 1 in a core
C
to write 0 in a core
D
to stop writing 1 in a core
Que.
32
the storage time of transistor is the part of the
A
turn on time
B
turn off time
C
fall time
D
rise time
Que.
33
if the turn on time of a transistor is decreases its turn on time
A
decreases
B
increases
C
is not affected
D
infinite
Que.
34
for an input pulse train of clock period T,the delay produced by an n
stage shift resister
A
(n-1)
B
2n
C
(n+1)T
D
2nT
Que.
35
If the memory chip size is 256*1 bits,then the member of chips required
to make up 1k bytes of memory is
A
32
B
24
C
12
D
8
Que.
36
In sign magnitude numbers
A
the leading bit stands for the sign
B
the leading bit is part of the magnitude
C
the leading bit is always zero
D
the leading bit is always
Que.
37
what is dule of X + X'Y =X + Y
A
X + Y = XY
B
X' + XY = XY
C
X(X' + Y) = XY
D
X'(X + Y) = X + Y
Que.
38
The "Pinch off" voltage of a JFET is 0.5 volts. Its "Cut Off" votage is
A
(0.5)^1/2 v
B
2.5 v
C
5.0 v
D
(5.0)^3/2 v
Que.
39
four independent message have bandwidth of 100hz, 200hz, and 400hz,respectively
each is sampled at the Nyquist rate and the samples are time division
multiplexed and transmitted sample rate is
A
1600
B
800
C
400
D
200
Que.
40
in the CMOS inventor 1.
Both are enchancement Type 2. One transistor
is N Channel and the other 3.
Both are N Channel with one enchancement
and the other depletion type 4. one is enchancement and the other depletion
type Of the above 4 statment the only true one are
