Objective Type Questions Electronics Communication Diploma

Give me Objective Type question paper for BSNL examination after passing Electronics Communication Diploma course ?

[Arun Vats]

Here I am giving you Objective Type question paper for BSNL examination after passing Electronics Communication Diploma course

1. To neglect a voltage source, the terminals across the source are

(A) open circuited

(B) short circuited (Ans)

(C) replaced by some resistance

(D) replaced by an inductor

2. Which is a digital communication system ?

(A) FM

(B) AM

(C) PCM (Ans)

(D) PAM

3. In a resonant circuit, the power factor at resonance is

(A) zero

(B) unity (Ans)

(C) 0.5

(D) 1.5

4. In TV systems the frame frequency is

(A) 100

(B) 60

(C) 50

(D) 25 (Ans)

5. The function 3 s has
(s + 1) (s + 2)

(A) one zero, two poles (Ans)

(B) no zero, one pole

(C) no zero, two poles

(D) one zero, no pole

Solution : G (s) = 3s has one zero at s = 0 and two poles at s = - 1, - 2.
(s + 1) (s + 2)

6. One electron volt is equivalent to

(A) 1.6 * 10-10 J

(B) 1.6 * 10-13 J

(C) 1.6 * 10-16 J

(D) 1.6 * 10-19 J (Ans)

7. Which of the following is donor impurity element ?

(A) Aluminium

(B) Boron

(C) Phosphorous (Ans)

(D) Indium.

8. The diameter of an atom is of the order

(A) 10-6 m

(B) 10-10 m (Ans)

(C) 10-15 m

(D) 10-21 m

9. A transistor is basically an amplifying device for

(A) power

(B) voltage

(C) current (Ans)

(D) all of these

10. If the d.c. valve of a rectified output is 300 V and peak to peak ripple voltage is 10 V, the ripple factor is

(A) 1.18%

(B) 3.33% (Ans)

(C) 3.36%

(D) 6.66%

Solution : rms value of output

= √3002 + 102 = 300.166 V

Average value = 300 V

Form factor RMS value = 300.166 = 1.00055.
Average value 300

Ripple factor = √(Form factor)2 - 1

= √(1.0005)2 - 1 = 0.0333

= 3.33%.

11. Full wave rectifier output has ripple factor of

(A) 1.11 (Ans)

(B) 1.21

(C) 1.41

(D) 1.51

12. In a common base connection IE = 2 mA, IC = 1.9 mA. The value of base current is

(A) 0.1 m (Ans)

(B) 0.2 mA

(C) 0.3 mA

(D) zero

Solution : IE = 2 mA IC = 1.9 mA

Ib = IE - IC = (2 - 1.9) = 0.1 mA.

13. For the action of transistor the base region must be

(A) P-type material

(B) N-type material

(C) very narrow (Ans)

(D) highly doped

14. Compared to a CB amplifier the CE amplifier has higher

(A) current amplification

(B) output dynamic resistance

(C) leakage current

(D) input dynamic resistance

(E) all of the above (Ans)

15. When a transistor is biased to cut-off its Y is

(A) 0.5

(B) 0

(C) 1.0 (Ans)

(D) 0.8

16. An ideal voltage amplifier should have

(A) Ri = 0, R0 = 0

(B) Ri = 0, R0 = ¥

(C) Ri = ¥, R0 = 0 (Ans)

(D) Ri = 0, R0 = ¥

17. Barichausen criterion for sustained oscillator is

(A) Aβ = 1 Ð00 (Ans)

(B) Aβ = 0

(C) Aβ = 1 Ð1800

(D) A = 1/√β

18. The value of plastic capacitance for a triode may range from

(A) 2 μF to 12 μF

(B) 20 μF to 120 μF

(C) 2 pF to 12 pF (Ans)

(D) 20 pF to 120 pF

19. A colpitts oscillator uses

(A) tapped coil

(B) inductive feedback

(C) tapped capacitance (Ans)

(D) no tuned LC circuit

20. A typical frequency for a RC feedback oscillator is

(A) 1 KHz (Ans)

(B) 100 MHz

(C) 1000 MHz

(D) 1 GHz

Will you please provide the Diploma In Electronics And Communication Engineering Digital Electronics exam question paper ?

[Quick Sam]

Here I am providing the list of few questions of Diploma In Electronics And Communication Engineering Digital Electronics exam question paper which you are looking for .
Diploma In Electronics And Communication Engineering Digital Electronics exam question paper
SECTION: A

1 a. Fill in the blanks with suitable words 5X1
(i) The radix of hexadecimal number system is _______________
(ii) The number of flip-flops required for decade counter is ______________
(iii) Race around condition is eleminated in ________________ flip flop
(iv) An example for unsaturated logic _________ Ics
(v) The SISO shift register with feed back _________ counter

b. Write a note interfacing between TTL and CMOS Ics 5

SECTION: B

2 a. Define the radix of a number system 2
b. Convert the following from Binary to Decimal number system 8
(i) 11001001 (ii) 1110.1111
(iii) 11001111 -->( )h (iv) 1AF--> ( ) D
c. Subtract the following using 2's complemnet method
(i) 1FE2- 0AC2 (ii) 412.6 - 255.0 5

3 a. Convert the following gray code to binary code (i) 110101 (ii) 111110 2
b. Convert the following Excess-3 code to binary code (i) 11011 (ii) 10110 3
c. Differentiate analog and digital signals 5
d. Expalin AND logic with symbol, logic expression and truth table, . 5

4 a. Define Noise Margin and power dissipation with reference to logic families 4
b. State Associative and Distributive laws of Boolean Algebra 4
c. Simplfy the following expressions and realize the same using gates
(i) A+(BC.(D+E)+ B)) (ii) (A+B).(C+D).(AB+CD) 7


SECTION: C

5 a. What is a Full adder? Use K- map to derive logic expressions for its output 7
b . Compare serial and parallel adders 3
c . Explain the operation of 4-bit parallel adder 5

6 a . What is a priority encoder? 2
b. Write the logic circuit and truth table of Decimal to BCD encoder 8
c. Write the logic circuit and truth table of BCD to seven segment decoder for common
anode display 5
7 a. What is a multiplexer? 2
b Explain the 8:1 multiplexer with the help truth table and logic circuit 6
c . What is the use of De-multiplexer? Write the truth table and logic circuit of
4:1 De-multiplexer 7

SECTION: D

8 a. Differentiate between combinational and seqential circuits 3
b . Explain the operation of clocked RS-FF using NAND gates 6
c. What is meant by Race around condition? How it is overcome? 7

9 a . Explain the logic diagram, truth table and timing diagram,
the operation of 4-bit ripple counter 8
b. What do you by modulus of counter? 2
c . Explain how decoding gates can be used for construction of mod-11 counter 5

10 a . Explain with logic diagram, truth table and timing diagram,
the operation of a 4-bit shift counter 8
b. Write the logic diagram of a 4-bit shift register.
Write the truth table and timing diagram for a 4-bit SISO register for a data of 1011 ( 7 )