ECIL Previous Year Question Paper with Answer

1. The register in the 8085A that is used to keep track of the memory address of the next op-code to be run in the program is the:

A. stack pointer

B. program counter

C. instruction pointer

D. accumulator

Ans-B



2. What is the typical invalid voltage for a binary signal?

A. 0.7–2.8 volts

B. 0.8–3 volts

C. 0.8–2 volts

D. 0.7–2.5 volts

Ans-C



3. Give the decimal value of binary 10010.

A. 610

B. 910

C. 1810

D. 2010

Ans-C



4. The output of a standard TTL NAND gate is used to pull an LED indicator LOW. The LED is in series with a 470- resistor. What is the current in the circuit when the LED is on?



A. 7.02 mA

B. 8.51 mA

C. 10.63 mA

D. 5.32 mA

Ans-A



5. One example for the use of a Schmitt trigger is as a(n):

A. switch debouncer

B. racer

C. astable oscillator

D. transition pulse generator

Ans-A



6. The GAL16V8 has:

A. 16 dedicated inputs.

B. 8 special function pins.

C. 8 pins that are used as inputs or outputs.

D. All of the above

Ans-C



7. A data conversion system may be used to interface a digital computer system to:

A. an analog output device

B. a digital output device

C. an analog input device

D. a digital printer

Ans-A

8. A 4-bit R/2R digital-to-analog (DAC) converter has a reference of 5 volts. What is the analog output for the input code 0101.

A. 0.3125 V

B. 3.125 V

C. 0.78125 V

D. –3.125 V

Ans-B



9. A binary-weighted digital-to-analog converter has a feedback resistor, Rf, of 12 k . If 50 A of current is through the resistor, the voltage out of the circuit is:

A. 0.6 V

B. –0.6 V

C. 0.1 V

D. –0.1 V

Ans-B



10. Distortion in transmission line is due to

A. Delay distortion

B. Phase distortion

C. Frequency distortion

D. All the above



11. The general parameters distributed along a transmission line are

A. R&L only

B. L&C only

C. C&G only

D. R, L, C&G







12. Phase distortion is prominently caused by

A. circuit transients

B. non linear characteristics

C. linearity

D. none



13. A network consisting of four terminals is called a

A. One port network

B. Two port network

C. Four port network

D. None of the above



14. Driving point of a network is

A. A port where voltage or current source is connected

B. A terminal where load is connected

C. A port where load is connected

D. None of the above



15. When two port networks are connected in parallel the resultant

A. Z parameters are the some of individual parameters

B. Y- parameters are the some of individual parameters

C. Both (a) and (b)

D. Neither (a) nor (b)



16. The response of a network is decided by the location of



A. Its poles

B. Its zeros

C. Either (a) nor (b)

D. Both (a) and (b)



17. Example of two port network is

A. Transformer

B. Transmission line

C. Bridge circuit and transistor circuit

D. All of the above



18. A system program that combines the separately compiled modules of a program into a form suitable for execution

A. assembler

B. linking loader

C. cross compiler

D. load and go

E. None of the above

Ans-B



19. A servo system must have

A. feedback system

B. power amplifier to amplify error

C. capacity to control position or its derivative

D. all of these

E. none of these

20. An open loop control system has its

A. control action independent of the output or desired quantity

B. controlling action, depending upon human judgment

C. internal system changes automatically taken care of

D. both (a) and (b)

E. all (a),(b) and (c)



21. Which of the following is the time domain method of determining stability of a control system

A. Bode plot

B. Nyquist plot

C. Nicholos chart

D. Routh-Hurwitz array

E. Constant M and (fy) locus

F. Root locus technique



22. Noise in a control system can be kept low by



A. reducing the bandwidth

B. attenuating such frequencies at which external signals get coupled into the system

C. both (a) and (b)

D. none of these



23. Which of following elements is not used in an automatic control system



A. sensor

B. error detector

C. oscillator

D. final control element



24. In control systems, excessive bandwidth should be avoided because



A. noise is proportional to bandwidth

B. it leads to low relative stability

C. it leads to slow speed of response

D. none of these



25. Saturation in a stable control system can cause



A. conditional stability

B. over damping

C. low level oscillations

D. high level oscillations



26. What is point-point link?



27. What is Multiple Access?



28. Which one of the following detectors is generally used in ac bridges for audio frequency range ?

A. Ac voltmeter

B. CRO

C. Headphones

D. Vibration galvanometer.

29. In which stage the following code

#include

gets replaced by the contents of the file stdio.h



A. During editing

B. During linking

C. During execution

D. During preprocessing

Ans-D



30. What will be the output of the program?



#include

#define SQUARE(x) x*x



int main()

{

float s=10, u=30, t=2, a;

a = 2*(s-u*t)/SQUARE(t);

printf("Result = %f", a);

return 0;

}

A. Result = -100.000000

B. Result = -25.000000

C. Result = 0.000000

D. Result = 100.000000

Ans-A



31. We want to round off x, a float, to an int value, The correct way to do is

A. y = (int)(x + 0.5)

B. y = int(x + 0.5)

C. y = (int)x + 0.5

D. y = (int)((int)x + 0.5)

Ans-A



32. What will be the output of the program?



#include

#include

void fun1(char, int, int *, float *, char *);

void fun2(char ch, ...);

void (*p1)(char, int, int *, float *, char *);

void (*p2)(char ch, ...);



int main()

{

char ch='A'; int i=10;

float f=3.14; char *p="Hello";

p1=fun1;

p2=fun2;

(*p1)(ch, i, &i, &f, p);

(*p2)(ch, i, &i, &f, p);

return 0;

}

void fun1(char ch, int i, int *pi, float *pf, char *p)

{

printf("%c %d %d %f %s \n", ch, i, *pi, *pf, p);

}

void fun2(char ch, ...)

{

int i, *pi; float *pf; char *p;

va_list list;

printf("%c ", ch);

va_start(list, ch);

i = va_arg(list, int);

printf("%d ", i);



pi = va_arg(list, int*);

printf("%d ", *pi);

pf = va_arg(list, float*);

printf("%f ", *pf);

p = va_arg(list, char *);

printf("%s", p);

A. A 10 3.14

A 10 3.14



B. A 10 10 3.140000 Hello

A 10 10 3.140000 Hello



C. A 10 Hello

A 10 Hello



D. Error

Ans-B



33. What function should be used to free the memory allocated by calloc() ?

A. dealloc();

B. malloc(variable_name, 0)

C. free();

D. memalloc(variable_name, 0)

Ans-C



34. he advantage(s) of incorporating the macro processor into pass 1 is/ are:



A. many functions do not have to be implemented twice

B. Functions are combined and it is not necessary to create intermediate files as output from the macro processor and input to the assembler

C. more flexibility is available to the programmer in which he/she may use all the features of the assembler in conjunction with macros

D. All of the above



35. Convert the ASCII/BEAR/assembly language pseudo-ops into hexadecimal machine language



A. 0111EF

B. 03 16

C. F8

D. 42 65 61 72

Ans-D

36. he action of parsing the source program into the proper syntactic classes is known as



A. syntax analysis

B. lexical analysis

C. interpretation analysis

D. general syntax analysis



37. The power carried by an electromagnetic wave traveling in free space changes with distance ‘d’ in proportion to



A. d

B. 1/d

C. 1/d2

D d2



38. In any transmitting antenna system, efficiency primarily depends upon



A Ohmic losses of various conductors

B. Radiation resistance

C. Ground conductivity

D. Atmospheric conditions



39. The antenna can be considered as



A. Matching the source and free space

B. Matching the source to the line

C. Matching the line and free space

D. None of these



40. As electromagnetic waves travel in free space, only one of the following can happen to them



A. Absorption

B. Attenuation

C. Reflection

D. Refraction



41. One of the following consists of non-resonant antenna:



A. The folded dipole

B. The rhombic antenna

C. The end fire array

D. The broad side array



42. The isotropic antenna is represented by



A. Dipole antenna

B. Rhombic antenna

C. Yagi uda antenna

D. No such antenna exists in practice



43. A helical antenna is used for satellite tracking because of its



A. Circular polarization

B. Maneuverability

C. Broad bandwidth

D. Good front " to " back ratio



44. The discone antenna is



A. A useful direction finding antenna

B. Used as a radar receiving antenna

C. Circularly polarized like other circular antenna

D. Useful as a VHF receiving antenna



45. The bandwidth of a radar receiver is inversely proportional to the



A. Pulse width

B. Pulse repetition frequency

C. Pulse interval

D. Square root of the peak transmitted power



46. A small circle on the output of a logic gate is used to represent the:



A. Comparator operation.

B. OR operation.

C. NOT operation.

D. AND operation.

Ans-C



47. What is the first thing you will need if you are going to use a macrofunction?



A. A complicated design project

B. An experienced design engineer

C. Good documentation

D. Experience in HDL



48. Which digital system translates coded characters into a more useful form?



A. encoder

B. display

C. counter

D. decoder

Ans-D



49. For a CMOS gate, which is the best speed-power product?



A. 1.4 pJ

B. 1.6 pJ

C. 2.4 pJ

D. 3.3 pJ

Ans-A



50. Which statement below best describes the function of a decoder?



A. A decoder will convert a decimal number into the proper binary equivalent.

B. A decoder will convert a binary number into a specific output representing a particular character or digit.

C. Decoders are used to prevent improper operation of digital systems.

D. Decoders are special ICs that are used to make it possible for one brand of computer to talk to another.

Ans-B