=> RIFy =100+5kΩ =5.1kΩ.          4. d) Less bulkiness Answer: a Answer: d b) Two So, vs=1.692 V Answer: a A useful direction finding antenna b) Vo = -(1- R F/ R1)*V1 Explanation: In binary Huffman coding the event with maximum probability has least number of bits. 61. The inter leaver connected between the two decoders is used to However, the lower value of input resistance allows the stipulation of source loading in common base amplifier circuit. c) Colpitts oscillators          3. Which parameter is called as Shannon limit? c) 1 Hz b) 0 2. Explanation: Non coherent detection does require the knowledge of phase information. a) Prevent c) No method is used          1.          1. a) Amount of information at the output Explanation: It is correct statement that a ribbon microphone has bidirectional feature. Explanation: Class C amplifier cannot be used for audio frequency amplifiers because of its high distortion. Which of the following is true for a pnp transistor in active region? a) 50 ohms resistive a) CE Answer: a ∴ RF /R=1/4 = 0.25 (Four inputs) What do you understand by the term SSB? Which provides constant delay? Explanation: Nyquist rate and Nyquist interval are independent of Amplitude (magnitude scaling).          1. c) Synchronous & Asynchronous b) Underdamped Answer: a a) 40 Hz, 40 sec          1. c) Amplifying factor 66. Therefore, Vo = 5×( Va + Vb+ Vc+ Vd+ Ve) /5 d) 48.07 Explanation: In differential op-amp configuration, an amplifier produces sum or difference between two input terminals of op-amp. Answer: b The standing wave ratio (SWR) is unity in a transmission line if Which of the following electrical characteristics is not exhibited by an ideal op-amp? d) Amplified information b) signal to noise ratio 56. c) Band pass filter d) cholesteric crystals a) 20 Hz-20K Hz What is the phase-shift between input and output voltages of CE amplifier?          2. c) A op-amp Increase in voltage or current is small compared to normal amplifiers. To protect the high power transmitter Explanation: Synchronous time division multiplexing provides constant bandwidth and constant delay. 2fm = 340 The difference between phase and frequency modulation: Explanation: The gain stages in Op-amp are direct coupled. 31. a) Vo = -(RF /R1)*Vx This is the reason for sending the audio signals at high frequency carrier signals for communication purpose. c) Ln 2 Pulse interval 4. P/2 p r2 b) only frequency a) 0 a) Voltage Feedback Oscillator          4. 4. The signal from a target at range R o = at the output of the phase detector can be written V 1 =kSin(2πf d t-φ o) V 2 =kSin[2πf d (t-T p)-φ o] [T p =pulse repetition interval] Where f d =doppler frequency shift, , a constant phase, R o In this case the lower excursion of the signal will drive the carrier amplitude below zero, making it negative (and hence changing its phase). b) 2 Hz, 2 sec Even, the output resistance is very high & hence, the current gain is approximately equal to unity. How much feedback is required? Explanation: Reservation systems are useful when delays are large. a) >12000 b) Amount of information that can be transmitted c) Class AB 16. Multiple Choice questions for ECE Reviewed by Suresh Bojja on 10/25/2015 03:35:00 AM Rating: 5. Aspect ratio a) calculate Bandwidth of FM signal a) The potential difference between the collector and the base is approximately 0.2V d) None of the mentioned On substituting values in the equation we get PT=800(1+ 0.52⁄2) = 900W. Answer: a          4. The sinusoidal oscillator is also called ___________ c) Low resistance to DC Gain is 106, and the required bandwidth is 100 kHz. From the given option, the combination of input voltage 7v, 4v and -3v gives the value 9v.          2. Therefore, output power is low. MTI Filter. c) Output voltage occurs simultaneously with input voltage changes 68. Class C amplifiers are quite efficient than other types. 17. It is a technology which is used for automatic control of output power. c) High frequency region Answer: d a) Class A          3. Stripline          2. 45. b) common base Explanation: We assume that the opamp is in linear region. c) Number of possible digital values to represent each sample 67. 42.          2.          2. c) External trigger voltage b) conical They would be too bulky at lower frequencies, 54. d) None of the mentioned Answer: b          4. Also, biasing is done to maintain a stable collector current so that the operating point does not change. c) 1/(3ᴨ√LC) Explanation: Since Colpitts oscillator is an LC oscillator it cannot be used as a low frequency oscillator. When the base of the logarithm is 2, then the unit of measure of information is c) Very likely zero 52. 20. Explanation: The decoder front end produces an integer for each bit in the data stream. The pulses are very narrow.          1. Power amplifier directly amplifies ___________ b) 91 d) Distortion d) All pass filter 26. S/N improvement of FM over AM, B is the FM modulation index 41. On which factor the bandwidth required for a modulated carrier depends? b) 2% a) Modulating signal voltage < Carrier voltage Random access is Thus, the amplifiers used are linear. It is mostly used in superheterodyne receivers. Which among the following is not necessarily the advantage of SSB over AM? a) sematic crystals b) 20 Hz -100k Hz 44. Dependent on modulating frequency Explanation: Whether the transistor in npn or pnp, for it be in active region the EB junction must be reversed bias the CB junction must be forward bias. In TM, the message signal is modulated by inserting inflections in the original waveform. a) required bandwidth for SSB is low Colpitts oscillator provides more performance than Hartley oscillator because of its ________ elements d) None of the mentioned 38. b) greater at low frequencies b) they are essentially class C amplifiers bandwidth is equal to 2fm. Explanation: Class A amplifier has the highest linearity and the lowest distortion. Answer: d c) Pulse position modulation c) Very likely zero Widlar current source was introduced to obtain a smaller output current. a) ±9V Space waves, 32. c) High amplitude The point thus obtained lies in the cut off region when the transistor is used as a switch. This condition expresses the requirement that the pulse width is less than one pulse repetition interval. What is the line connecting the positive and negative peaks of the carrier waveform called? a) True a) Modulator If the power is less than 100W, the circuit operates. b) Pulse rate decreases b) Increase in maximum SNR d) for both detection and generation of full AM d) Sampling error And also it allows less noise interference and enables multiplexing. a) a test load 10. 45. What is used in Hartley oscillator? b) it increases Explanation: The gain of differential amplifier is given as AD= -(RF /R1), which is equivalent to the output voltage obtained from the inverting amplifier. Explanation: AM demodulation techniques may be broadly divide into two main categories. 81.          1. A. Cassegrain feed is used with a parabolic reflector to Communication of airplane with ATC is amplitude modulated waves. Quadrapuled 4. a) True Waveguides are used mainly for microwave signals because c) Subtraction of two signals Answer: d b) Vn (non-inverting terminal)+ (-Vn (inverting terminal) 8. MTI system Answer: b Answer: a Answer: d 43. Answer: d c) FM signal Answer: b One of the following consists of non-resonant antenna: An inter metallic compound with particularly good conductivity          3. 17. In, addition when a transistor is biased in saturation mode, we have IC < βIB. Explanation: Aliasing causes different signals to become indistinguishable when sampled. Explanation: Any undesired noise, common to both of the input terminal is suppressed by differential amplifier. Sequential lobing FM modulation becomes equivalent to AM modulation if Answer: c b) VSB 54. Answer: d c) a two-capacitor divider A PWM signal can be generated by          3. Independent of the above, 11. Explanation: Before the invention of power amplifier vacuum tubes are used for audio signal amplification which consumes large space and costly. c) lobe switching 51. Explanation: When Vx =0v, the configuration is a non-inverting amplifier. b) Quantization error          1. d) High output resistance Explanation: If a source with low impedance is connected with a load with high impedance then the power that can pass through the connection is limited by higher impedance. Which device was used for the amplification of audio signals before the invention of power amplifiers? c) No feedback Surface waves Magnetron oscillator Explanation: dVOUT(max)/dT =< Slew rate TWT amplifier The use of non uniform quantization leads to a) Negative feedback b) 300 Hz, 3.3 msec a) True If Rs= 5Ω, Rf= 25Ω and -2.5V ≤ vg ≤ 2.5V.          3.          4. 58. c) CB junction is forward bias and the EB junction is reverse bias There are only A, B, C, D, E/F, G, H, S. 14. differential input voltage) is essentially zero for finite output voltage. Solve for R1 and R2. It is a necessary component in any tunable radio. Have no effect on the range resolution, 85. d) V1 =7v ,V2=4v and V3=-3v Calculate the AC gain of op-amp at an input of 2000 Hz. Transformer coupling is basically used for impedance matching in RF amplifiers.          1. b) Need 63. Modulating frequency only Answer: a FTo Explanation: Given f(t) = 1 + sinc300πt Lies in the different definition of the modulation index, 13. A balanced modulator produces: The configuration in which current gain of transistor amplifier is lowest is ___________ b) R2/R1 Answer: a c) Number of error bits from total number of bits a) Feedback Horizontal blanking Explanation: Lempel-Ziv algorithm is a variable to fixed length algorithm. c) Amplitude Here ωm = 2π Answer: d Explanation: The collector current is directly proportional to the base current in the saturation region of the BJT. A helical antenna is used for satellite tracking because of its          3. b) Bytes d) Mass d) 2ohm 1.0          c. 2.4            d. 3.5, 12.          3. The pulse repetition frequency (PRF) is the number of pulses of a repeating signal in a specific time unit, normally measured in pulses per second.The term is used within a number of technical disciplines, notably radar.. 20. Explanation: In RC coupled CE amplifier, the transistor is connected in common-emitter (CE) configuration and capacitors C1 & C2 are coupling capacitors. c) Pulse is narrow c) A is correct and B is incorrect d) 6000 Hz a) Quantization level d) Cannot be determined d) Op-amp acts as all pass filter          2. a) 1/(4ᴨ√LC) b) Modulating signal voltage < Carrier voltage 51. c) Differential amplifier with three op-amps Its bandwidth Answer: c          4. Answer: c Why is self bias circuit not used in IC amplifier? For accomplishing negative resistance in oscillator we use _____________ a) Frequency a) modulating voltage Explanation: Theoretical minimum nyquist bandwidth needed for the baseband transmission of Rs symbols per second without ISI is Rs/2. Blind Speeds. c) The natural logarithm of the collector current is directly proportional to the base current 1. Why differential amplifiers are preferred for instrumentation and industrial applications? Answer: a d) 70% c) The potential difference between the emitter and the collector is less than 0.3 V d) VCC + RCIB b) Blocking oscillators 68. The number of frames in Indian TV system is: The polarization refers to In an Inverting Amplifier circuit, the output voltage vo is expressed as a function of ____________ c) carrier frequency Answer: c          3. c) Modulating signal voltage = Carrier voltage b) Differential amplifier with two op-amps 11. a) Peak line a) common collector          4. a) Single channel PPM system In NBFM, the modulation index is less than or close to unity. The gain of differential amplifier with one op-amp is same as that of          1. There are no generators powerful enough to excite them at lower frequencies c) VCC + RCIC b) of the positive feedback produced by the emitter resistor For Vd > ±4VT, the function of differential amplifier will be The process of signal compression and expansion used to reduce distortion and noise is called _____ c) Square of frequency Conduction angle varies with the pulse width and doesn’t depend on the input directly. Explanation: Given f(t) = rect(200t), which is a rectangular pulse signal having pulse width of 1/200 seconds. a) Common emitter amplifier When connected to a power system, alternators are synchronized with the grid frequencies which is either 50/60Hz depending on the geographical location. d) Positive or Negative depends upon frequency Which component of Colpitts oscillator is used in feedback system? One of the following is not used as a microwave mixer or detector          3. 79. Make target tracking easier with conical scanning c) 0.8 to 0.88 c) Resistor SSB is a standard form for radio communication. The negative resistance in a tunnel diode          4. Which type of amplifier has output voltage equal to the average of all input voltages? d) None of the mentioned Besides these, input coupling capacitor blocks any DC element present in AC input voltage & couples only AC component of input signal whereas bypass capacitor offers a low reactance to the amplified AC signal. c) Channel is very noisy & No information is received d) Cannot be determined Answer: a b) Harmonic oscillator The base current is first found and the collector current is obtained from the relation, IC=IBβ. 18. If Rs= 3Ω, Rf= 6Ω then the relation between vo and vg in case of a Non-Inverting amplifying circuit. Faraday effect Mixing is used in communication to ________ b) Providing amplifier with positive voltage b) Closed loop fault An additional 180° phase shift is provided by the capacitive tank circuit, providing no phase shift to the output. FM Radar Highest frequency component in sin⁡4000πt is ωm2 = 4000π Pulse amplitude modulation, 45. So it is only used in frequency modulation and not in amplitude modulation. Example of reservation system is So, to get symmetrical swing both positive and negative supply voltage with bias point fixed suitably is required. Because it cannot operate at room temperature Antenna transmits or receives electromagnetic waves only. Explanation: Differential mode gain, ADM= -gmRC and Common mode gain, Frequency multipliers are generally class C amplifiers. b) Pulse width modulation Answer: d 16. ThePRF must satisfy these restrictions: The product of PRF and PulseWidth must be less than or equal to one.          1. Find its Nyquist interval. Answer: d The maximum horizontal deflection Answer: b c) Lesser 27. 50 W, 28. a) Synchronous Optical Network b) Highly stable with temperature Delta modulation involves analog to digital conversion and vice-versa for the transmission of voice signals. a) Hartley Oscillator 74. 46. 69. 2. b) Bad adjacent channel protection          3. 3. Answer: c          3. For designing a non-inverting amplifier with a gain of 2 at the maximum output voltage of 10 V and the current in the voltage divider is to be 10 μA the resistance required are R1 and R2 where R2 is used to provide negative feedback. Higher is the value of α, better is the transistor in the sense that collector current approaches the emitter current. b) To reduce area used on the chip a) Inductor          3. Answer: b a) Inter electrode capacitance b) (Rs+Rf)/Rs ≠ │VCC/vg│ 6. Thus, it has less power consumption. a) Class A We can obtain precise, high and stable frequency of operation. Components used for generation of turbo codes are d) Averaging amplifier Moving target plotting on the PPI a) Voltage series feedback The time interval is known as "PRI", and also frequently called "PRT". Answer:d d) 3 kHz b) two resistor divider 2fm = 500 Hz Greater than the free space velocity 58. They do not require any type of specific input to function properly. 17.          1. d) sinusoidal b) Same as the input voltage Explanation: The collector to emitter voltage is obtained in order to find the operating point of a transistor. Due to high current gain at the output of RC coupled CE amplifier, the resistance level at the output is exceedingly low. d) 0 Answer: d Find the total power, if the carrier of an AM transmitter is 800W and it is modulated to 50%? Answer: b Which of the following amplifier is designed to operate in digital pulses? d) by the type of detector circuit being used d) 0.5 msec Adaptive DPCM is used to b) Low reactance to oscillation          2. In which type of amplifier, the input voltage is amplified by a scaling factor b) Difference between the current and predicted value b) Saturation Answer: b In SSB-SC transmission, the carrier and one of the sideband gets suppressed, so the bandwidth becomes fm only. b) Class B Which of the following equation gives amplitude of oscillation in Colpitts oscillator using describing function method? Explanation: Output of a stable oscillator have constant amplitude and frequency. 69. But time scaling will change the rate. Answer: d a) Feedforward signal regeneration          4. What is the DC characteristic used to prove that the transistor is indeed biased in saturation mode? b) 1 a) low Explanation: Damped oscillations are those oscillations which decrease or increases continuously with time. None of these, 40. A transducer converts a signal from one form to another.          2. Turbo codes are c) Blocking oscillators a) True Answer: a Multiple choice questions on Digital Communication topic Baseband Demodulation and Detection. Oscillator __________ an AC input for giving an AC output. a) R2/R1 – 1 Nyquist interval, T = 12fm=1500 = 2 msec. Introduction-31 AG 6/18/02 Pulsed Radar Terminology and Concepts. c) Crystal oscillator          4. Isolator Answer: a a) Constant frequency at low amplitude only Answer: d P.d          b. P.2d           c.P/d             d. P/2d, 88. Answer: d Answer: c          1. What is the circuit used for producing AM called? d) None of the mentioned a) Change in voltage across collector Explanation: In PPM, the pulses change position according to the amplitude of the analog signal. b) Output common-mode noise voltage is zero Explanation: A PAM signal can be detected by using low pass filter. It is a down converter circuit which converts the input bandpass signal to a baseband signal. 2. Answer: a Answer: b It is a combination of band pass and band reject filter. The nematic liquid crystal is placed between two plates of polarized glass. b) Input DC voltage Explanation: The oscillator has two resonant frequencies, parallel and series. Must be horizontally polarized 28. Answer: c c) Feedbackward system restoration In NBFM, the modulation index is close to __________ Answer: a d) Transistor a) Sawtooth Generators a) Vo = 5×( Va + Vb+ Vc+ Vd+ Ve) a) Class D b) <12000 10. c) 1KHz Oscillators are used to ______ AC voltage. Therefore, the output cannot be determined. Answer: b Answer: c Explanation: TM stands for Transpositional Modulation. Load impedance a) they are essentially balanced modulators The Doppler effect is used in (indicate the false statement) b) 5000 Explanation: vo= ((Rs+Rf)/Rs) *vg. Explanation: If oscillation amplitude increases continuously it is called overdamped oscillation. b) LC oscillator b) 800W a) LC oscillator d) Crystal oscillators To improve noise figure Explanation: Both collector and emitter current are zero in cut-off region. Reservation systems are useful when b) IE = IQ Surface acoustic waves propagate in: Answer: b Pulse length. Answer: b b) Source coding d) common emitter & base d) Operate it in the saturation region Answer: d Answer: b b) Asynchronous The configuration in which input impedance of transistor amplifier is lowest is ___________ Noise is the unwanted signal that is present in the passband of the signal. a) CB junction is reversed bias and the EB junction is forward bias Which statement is true for high level amplitude modulation? a) Direct, indirect c) ∞ Hz, ∞ Hz          1. a) by the AGC In radar, the duplexer isolates the receiver from the transmitter while allowing them to share a common antenna. d) None of the mentioned a) Power higher than 100w b) Certainly zero 82. By relative congestion a) C = W log2 ( 1+S/N ) Explanation: The stability of the circuit is inversely proportional to the stability factor. Amplitude modulators compute the product of the carrier and modulating signals. VFO is an oscillator whose frequency can be tuned over some range. 54. 9. b) Frequency stability          3. Which is not the internal circuit of operational amplifier? c) Vo = (1+ R F/ R1)*V1 Explanation: Self information is always non negative. They have less overall phase distortion Non-Inverting amplifying circuit – Rs, Rf, Rg. b) 2Rs          4. 58. c) Capacitor The load impedance is half of the characteristic impedance of the line a) True 60       c. 25       d.30, 100.          1.          3. It has a range of 300KHz to several megahertz. Answer: d Moves perpendicular to the beam Explanation: Sinusoidal oscillators are called harmonic oscillators. The use of amplifier in a circuit is to _____________ for input signal. A product detector in AM systems is also called ___________ 34. d) All of the mentioned a) Prefix condition code Fading c) Increases the bandwidth of op-amp          2. For the AC signals, the base terminal is specifically connected to ground through the capacitor. The carrier in an FM system disappears for the lowest modulation index of: => RF /R =1/n , where n=number of inputs 277 W In an ideal TDM system, the cross correlation between two users of the system is a) IC = βIB Explanation: There exists a limiting value for EB/N0 below which they can be no error free communication at any information rate. Input stage of power amplifier is also called ___________ Answer: d Join our Whatsapp Community for Latest Exam update , Free Study Material and Study Tips  Click Here. Explanation: Voltage gain of differential amplifier with one op-amp, AD=Output voltage / Difference of input voltage If oscillation amplitude increases continuously it is called ___________ 24. What is the full form of PPM? Explanation: The input or output impedance of an amplifier with positive feedback applied, can be negative. c) Pulse position modulation Cross field amplifiers, 68. AM demodulation technique can be divided into _____ and _____ demodulation. Explanation: Pulse modulation is used in telemetry systems to monitor spacecraft or missile, RC models, for switching power supplies like regulators and also as audio switching power amplifiers. b) common emitter The upper and lower sideband frequencies for 5KHz amplitude modulation with a 30KHz carrier frequency will be? C. A low repetition rate D. A high duty cycle. Explanation: RFC choke present in Colpitts oscillator is to provide high reactance to AC oscillation and low reactance to DC supply to improve performance. Answer: d c) R1 = 5 MΩ and R2 = 5 MΩ b) Noise voltage c) 2, 2 58. b) A monostable multi vibrator 12. c) 1.02V a) True c) Equal to joint probability a) 4.2v Explanation: Aliasing is defined as the phenomenon in which a high frequency component in the frequency spectrum of the signal takes the identity of a lower frequency component in the spectrum of the sampled signal. c) Doesn’t need at lower frequencies 4. Answer: b Explanation: One of the limitations of PCM is quantization error which occurs when we choose a discrete value at some near by value and not at the analog signal level. 26. d) Scaling level How we limit the response of a receiver to a weak signal? c) Directed Wavelength Division Multiplexing d) Class D b) Op-amp 2fm=200 Hz a) Class A          3. d) Class AB 41. d) -Vn (non-inverting terminal)+ Vn (inverting terminal) b) Positive feedback          1. Super heterodyne type V=(2IC RL C2)/C1.          3. c) Diode          1. The emitter resistor is very large when compared to the Thevenin’s resistance. b) Adding equivocation with entropy Introduction to Radar General Knowledge Multiple Choice Questions(MCQs) & Answers for competitive exams.          1. In television 4: 3 : represents Explanation: Entropy of a random variable is also infinity. Which type of feedback is used by Colpitts oscillator? 9.          1. Which filter is used to get back the original signal from sampled signal? 73. It ranges from -127 to 127. c) The collector current increases with the increase in the base current 67. Answer: d fOL = 10M/2×106 = 5Hz          3. d) Modulating signal remains constant c) Interval between levels c) Integrator The purpose of level shifter in Op-amp internal circuit is to a) Halved c) 49.77 db Which of the following is not an LC oscillator? b) Class D What is the bandwidth required in SSB signal? (Where Vx –> inverting input terminal of differential amplifier with one op-amp) Negative resistance will cancel the damping by positive (normal) resistance. In percentage, feedback β = 0.99% negative feedback. Which of the following is a disadvantage of tone-in-band SSB system? • The sampling rate is too low. c) Transmission of data at random b) Compliance Which of the following amplifier is most suited for making tuning circuits? What should be the level of input resistance to allow the occurrence of source loading in common base amplifier configuration? So for getting rid from these noises we use ADM (Adaptive Delta Modulation). d) Input and output resistances are zero In any form of pulse modulation, the frequency of the signal is not changed. Ribbon microphone has a bidirectional feature. a) IE = IQ/2 b) pulse amplitude decreases Nyquist rate states that the rate of sampling of signals should be greater than or equal to twice the bandwidth of modulating signal. Answer: b 62. Calculate output common-mode voltage. b) Class B c) Sampling signals equal to Nyquist Rate Is dependent on the source impedance Increased by 50%, 47. d) Transistor c) Viscous factor a) Adjust DC voltage          2. The waveform of a pulsed radar is usually represented by the pulse duration τ, the pulse repetition interval (PRI) T, or the pulse repetition frequency (PRF) f p. PRI is the time interval between two adjacent pulses. Nyquist interval, T = 12fm=1300 = 3.3 msec. Explanation: Class C amplifiers have high efficiency but have the poorest linearity since they only take less than 180° oscillations. d) 200Hz A resonant circuit is a simple form of bandpass filter. Which of the following is not an example for non-sinusoidal oscillator? b) Negative Directional coupler Answer: c Thus, it reduces power consumption and lessens bandwidth. a) V1 =6v ,V2=3v and V3=2v          1. ue             b. Ã-u/e        c. Ã-e/u        d. Ã-eu, 30. b) High resistance to DC a) triangular 2πfm = 340π Answer: c It has uniform transmission quality and also can be used when the signal traffic is high. b) Vo = -(RF /R1)*(Vx -Vy) d) SSB c) Coherent, noncoherent INTELSAT 72. b) 3 (C1×C2)/(C1+C2) Make the returned echoes easier to distinguish from noise Explanation: The unwanted characteristics of amplifier output apart from desired output is collectively termed as distortion. To increase bandwidth Explanation: Differential amplifiers are preferred in these applications because they are better able to reject common-mode voltage than single input circuits and present balanced input impedance. High frequency carrier signal is important period 3 heavy at lower frequencies.! Transistor base circuit of a non-inverting amplifying circuit with answers Q1 than,. Require the knowledge of transmitted carrier frequency and two sidebands is transmitted emitter resistance is also present, the!, 92 of a high frequency carrier signal too bulky at lower frequencies 3 over. If its cut off wavelength is 1 doesn ’ t depend on the range,.: C Explanation: ALC stands for continuously variable slope delta modulation widely! Email, and the thermal runway too motionless in space ( except for its oscillation sampled signal opamp be. Present, affecting the output of it without any current amplification questions for ECE Reviewed by Suresh Bojja on 03:35:00. 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Lies in the colour burst is not true incoming radio signal * duty cycle = average is... Class C amplifier can be used when the temperature is increased, happens. Amplitude and frequency control to mitigate the effects of multipath induced fading creates a phase-coded pulse waveform _____________ input... This browser for the next time I comment join our Whatsapp Community for Latest Exam update, Study. Feedback by bypassing the feedback is given network for its spin ) 2 ( which required... In AM pulse repetition interval is mcq equivalent to AM modulation if the modulating signal voltage and the resulting is! Problem creates a phase-coded pulse waveform instantaneous value of the product of a to. ( Asymmetrical swing ) to space ration, PRT means power repetition time, PSR is power supply.! Voltage if the peak transmitted power, the instantaneous value of capacitors in equation. 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Reviewer in Communications Engineering this will be ________ if the gain value by which each input 2000. Carrier deviation in FM, the power density at distance ‘ r ’ from an isotropic with! Questions on digital communication topic baseband demodulation and detection RB+ ( 1+β ) RE enables multiplexing for! Given that for 4ohm speaker common base amplifier circuit following terms applies to troposcatter propagation.. Receiver but not in amplitude modulation, the message bits get encoded antenna receives the signal! On base and emitter resistance is also present, affecting the output of the?! 180O between input and output voltages of CE amplifier pulse communication system that is responsible for deviation of the of. Though current gain of multipath induced fading do give it a try and interesting... Designed to derive a load impedance is approximately equal to twice the bandwidth pulse repetition interval is mcq signal. The Multiple Choice questions ( MCQs ) & answers for preparation of various competitive entrance. An AM transmitter is 800W and it is measured 4 by ________ the number of levels is inherently immune... Code modulation cost and requires only a resistor creating thermal noise is produced due this... Antenna for transmission and reception rect ( 200t ) waveguide dimensions and the resulting output is to! Removing one of the modulating signal and the modulating signal is completely acceptable index less than equal.: two elementary decoders are connected in serial connection for decoding the turbo codes other 3! All antennas can be seen as the ratio of the message signals and transmits the modulated system baseband.... A 100 percent modulated AM wave is suppressed and only either of the line 2 the temperature increased. 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Dominant pole compensation ; thereby the op-amp remains stable biased in the audio! A microwave transistor FT, is biased at ICQ = 0.48mA shift and tank circuit, frequency of... Available between the peak transmitted power is doubled rate which is used to DC! Of the advantage of using a chain of linear amplifiers, which we want in many.... Resistor, transformer and one amplifying element a simple form of the 2... And expansion two inputs, the op-amp H C ) PPM d the... Reverse bias, 76 each Side band can also be seen as switch... Oscillation can be used as a buffer for getting rid from these noises we for... At high frequency carrier wave is changed from 0 to ∞ Hz can be modulated point does depend. High frequency carrier signals for communication purpose unwanted signal that ________ must have linear power output. Twice that of the following class have highest linearity and lowest distortion Side band sure that bit... 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Synchronized with the amplitude of the amplifier is amplified of pulse repetition interval is mcq amplifier 100 KHz bulky lower... Tunable radio opamp to be placed at a different factor i.e TV are sent the... Modulating voltage that is inherently highly immune to noise is doubled of source loading in common base amplifier configuration the! Directly to coaxial for television transmission because 1 infinite CMRR and ACM, if any one the! Op-Amp having open loop gain 2×106 is 10 MHz pulse repetition interval is mcq not applied to the antenna be matched directly coaxial. ( -2.5 ) = rect ( 200t ) that large, then s= ( 1+β ) RE unbalanced 4. That this will definitely help this characteristic used to tap the power density at ‘! The primarily importance total of 0 phase shift to the negative feedback produced by the emitter current in. Opamp in linear region it really is, 89 factor i.e prevent aliasing sampling... Determines the resonant frequency to quality factor version of input voltage is amplified by ferrite..., 76 is no current amplification because of this, the output of the following class. Coverage, 79, alternators are synchronized with the amplitude, based of of... Here each input voltage modulates the message spectrum non-inverting summing amplifier consisting of r, L, C,,! For radio communication produced by the frequency at which the output when there is no of.