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ELECTRONICS CAREER www. ecatn. blogspot. We will write a custom essay sample on Barc Sample Paper or any similar topic only for you Order Now com BARC SAMPLE QUESTION PAPER FOR ELECTRONICS If you like my site please support us by sharing website (www. ecatn. blogspot. com) to your friends 1. Differential amplifiers are used in a. instrumentation amplifiers b. voltage followers c. voltage regulators d. buffers 2. The output voltage Vo of the above circuit is a. -6V b. -5V c. -1. 2V d. -0. 2V 3. The ideal OP-AMP has the following characteristics. a) Ri=? ,A=? ,R0=0 b) Ri=0 ,A=? ,R0=0 c) Ri=? ,A=? ,R0=? d) Ri=0 ,A=? ,R0=? ELECTRONICS CAREER www. ecatn. blogspot. com 4. . How many op-amps are required to implement this equation A. B. 3 C. 4 D. 1 5. A very brief, high voltage spike on an ac power line is called as A. A bleeder B. An arc C. A transient D. An avalanche E. A clipped peak 6. You can find the zener diode in A. The mixer in a superheterodyne receiver B. The PLL in a circuit for detecting FM C. The product detector in a receiver for SSB D. The voltage regulator in a power supply E. The AF oscillator in an AFSK transm itter 7. A network function can be completely specified by: (A) Real parts of zeros (B)Poles and zeros (C)Real parts of poles (D)Poles, zeros and a scale factor 8. A unit impulse voltage is applied to one port network having two inear components. If the current through the network is 0 for t0 and decaysexponentially for t0then the network consists of (A) R and L in series (B)R and L in parallel (C)R and C in parallel (D)R and C in series ELECTRONICS CAREER www. ecatn. blogspot. com 9. The Q-factor of a parallel resonance circuit consisting of an inductance of value 1mH, capacitance of value 10-5F and a resistance of 100 ohms is (A) 1 (B)10 (C) ? 20 (D) 100 10. In a travelling electromagnetic wave, E and H vector fields are (A) (B) (C) (D) perpendicular in space . parallel in space. E is in the direction of wave travel. H is in the direction of wave travel. 11. The lower cut-off frequency of a rectangular waveguide with inside dimensions (3 ? 4. 5 cm) operating at 10 GHz is (A) 10 GHz. (B)9 GHz. (C) 10/9GHz. (D) 10/3GHz. 12. The intrinsic impedance of free space is (A) 75 ohm. (B)73 ohm. (C)120 ? ohm. (D)377ohm. 13. Which one of the following conditions will not gurantee a distortionless transmission line (A)R = 0 = G (B)RC = LG (C) very low frequency range (R ? L, G ? C) (D) very high frequency range (R ? L, G ? C) 14. MOSFET can be used as a ELECTRONICS CAREER www. ecatn. blogspot. com a) current controlled capacitor (b) voltage controlled capacitor (c) current controlled inductor (d) voltage controlled inductors 15. In a common emitter, unbypassed resister provides (a)voltage shunt feedback (b)current series feedback (c)negative voltage feedback (d)positive current feedback 16. Introducing a resistor in the emitter of a common amplifier stabilizes the dc operating point against variations in a) Only the temperature b) only the ? of the transistor c) Both Temperature ? d) None of the above 17. For the circuit shown in Fig. 4, the voltage across the last resistor is V. All resistors are of ? 1 . The Vs is given by (A) 13V. (C) 4V. (B) 8V. (D)1V. 18. The network has a network function Z(s)=s(s+2)/(s+3)(s+4) (A)not a positive real function. (B)RL network. (C) RC network. (D)LC network. 19. For a series R-C circuit excited by a d-c voltageof 10V, and with time- constant s, , ? the voltage across C at time ? = t is given by A. 10(1-e-1) v ELECTRONICS CAREER www. ecatn. blogspot. com B. 10(2-e-2) v C. 10-e-1 volts D. 1-e-1 20. A 2 port network using Z parameter representation is said to be reciprocal if A. Z11 =Z22 B. Z12 =Z21 C. Z12 = – Z21 D. Z11 – 2Z22 =0 21. Consider a transmission line of characteristic impedance 50 ohms and he line is terminated at one end by +j50 ohms, the VSWR produced in the transmission line will be (A) +1 (C)infinity (B)zero (D)-1 22. In a certain medium E = 10 Cos(108t – 3y) ax V/m. What type of medium is it? (A) Free space (B)Lossy dielectric (C)Lossless dielectric (D)Perfect conductor 23. If D ? ? =? ?. E and ?. J = ? ?. E in a given material, the material is said to be (A) Linear (C) Isotropic (B)Homogeneous (D) Linear Homogeneous 24. For a 300 ? antenna operating with 5A of current, the radiated power is (A) 7500 W (B) 750 W ELECTRONICS CAREER www. ecatn. blogspot. com (C)75 W (D)7500 mW 25. An OPAMP has a slew rate of 5 V/ µ S . The largest sine wave O/P voltage possible at a frequency of 1MHZ is (a) 10 volts (c) 5/3 vo lts (b) 15 volts (d)5/2 volts 26. The early effect in a bipolar junction transistor is caused by (a) fast turn-on (b)fast turn-off (c) large collector-base reverse bias (d) large emitter-base forward bias 27. MOSFET can be used as a (a) current controlled capacitor (c) current controlled inductor (b) voltage controlled capacitor (d) voltage controlled inductors 28. An AM signal is detected using an envelop detector. The carrier frequency and modulating signal frequencyare 1 MHz and 2 kHz respectively. An appropriate valuefor the time constant of the envelope detector is. (A) 500  µsec (C) 0. 2  µsec (B) 20  µsec (D) 1  µsec 29. An AM modulator has output x(t)=A cos400? t+Bcos 380? t +Bcos 420? t and The carrier power is 100 W and the efficiency is 40%. The value of A and B are (A) 14. 14, 8. 16 (C) 22. 36, 13. 46 (B) 50, 10 (D) None of the above ELECTRONICS CAREER www. ecatn. blogspot. com 30. A super heterodyne receiver is designed to receive transmitted signals between 5 and 10 MHz. High-side tuning is to be used. The tuning range of the local oscillator for IF frequency 500 kHz would be (A) 4. 5 MHz – 9. MHz (C) 4. 5 MHz – 10. 5 MHz (B) 5. 5 MHz – 10. 5 MHz (D) none of these 31. An analog signal is sampled at 36 kHz and quantized into 256 levels. The time duration of a bit of the binary coded signal is: (A) 5. 78 µs (C) 6. 43 ms (B) 3. 47 µs (D) 7. 86 ms 32. The minimum sampling frequency (in samples/sec) required to reconstruct the following si gnal form its samples without distortion would be x(t)= 5(sin2? 1000t/? t)3 +7(sin 2? t 1000t/? t)2 (A)2Ãâ€"103 (C) 6Ãâ€"103 (B)4Ãâ€"103 (D) 8Ãâ€"103 33. Three identical amplifier, each having a spot effective input noise temperature of 125 K and available power G are cascaded. The overall spot effective input noise temperature of the cascade is 155 K. The G is (A) 3 (C) 7 (B) 5 (D) 9 34. In the Op-Amp circuit shown, assume that the diode current follows the equation I=Isexp(V/Vt) Vi=2V , Vo =V01 and for Vi=4V , Vo =V02 The relationship between V01 andV02 is ELECTRONICS CAREER www. ecatn. blogspot. com (A) (B) (C) (D) V02=v2 V01 V02=e2 V01 V02= V01ln2 V01- V02=Vt ln2 35. The counter shown in fig. below is a (A) MOD–8 up counter (B) MOD–8 down counter (C) MOD–6 up counter (D) MOD–6 down counter 36. The MUX shown in fig. multiplexer. The output Z is (A) A xor C (C) B xor C (B) A and C (D) B and C How to cite Barc Sample Paper, Papers