Compare Class A ,Class B, Class C and class AB power amplifiers on the basis of: i)Angle of conduction ii)Efficiency iii)Position of operating pointing power dissipation iv)Distortion

Compare Class A ,Class B, Class C and class AB power amplifiers on the basis of: i)Angle of conduction ii)Efficiency iii)Position of operating pointing power dissipation iv)Distortion
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Compare Class A ,Class B, Class C and class AB power amplifiers on the basis of: i)Angle of conduction ii)Efficiency iii)Position of operating pointing power dissipation iv)Distortion

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Compare between class A and class B amplifier on the basis of (i) Efficiency (ii) Power (iii) Position of Q- point (iv) O/P distortion

Description : Compare between class A and class B amplifier on the basis of (i) Efficiency (ii) Power (iii) Position of Q- point (iv) O/P distortion

Last Answer : Parameter Class A Class B 

Classify the power amplifiers on the basis of operation and input/output waveforms.

Description : Classify the power amplifiers on the basis of operation and input/output waveforms.

Last Answer : Depending upon the operation and input/output waveforms power amplifiers are classified into following type. 1) Class A amplifier. 2) Class B amplifier. 3) Class C amplifier. 4) Class AB amplifier. 5) Class D amplifier

Define following terms related to logic families : (i) Noise Margin (ii) FAN-OUT (iii) Propagation delay (iv) Power dissipation

Description : Define following terms related to logic families : (i) Noise Margin (ii) FAN-OUT (iii) Propagation delay (iv) Power dissipation

Last Answer : i) Noise immunity is measured in terms of noise margin. High state Noise margin = VNH = VOH(min) - VIH(min) Low state Noise margin = VNL = VIL(max) - VOL(max) i) The fan-out is defined as the ... logical 0 state (HIGH to LOW) iii) Average power dissipation is defined as PD(avg) = ICC(avg) * VCC

Explain with circuit diagram and waveform the operation of class AB push pull power amplifier.

Description : Explain with circuit diagram and waveform the operation of class AB push pull power amplifier.

Last Answer : Class AB Push Pull Power Amplifier:  Circuit Diagram:  Circuit Decription: The circuit consists of two centre-tapped transformers T1 and T2, two identical transistors Q1 and Q2 , Resistor R and ... two halves & produces a full sine wave in the load resistor. Waveform :

Draw the circuit diagram of class AB power amplifier and describe its working.

Description : Draw the circuit diagram of class AB power amplifier and describe its working.

Last Answer : Circuit diagram: Circuit Description: The circuit consists of two center-tapped transformers T1 and T2, two identical transistors Q1 and Q2 , Resistor R and diode D. The DC voltage ... and Q2 conduct, as soon as input cross zero, negative sinusoidal voltage will appear across load.

Cross over distortion in class - B push-p amplifiers:

Description : Cross over distortion in class - B push-p amplifiers:  1. Is due to transistor operating near saturation region  2. Can be eliminated by operating them in class operation  3. Occurs because two power transistors do not exactly matching parameters  4. Always occurs in low signal area

Last Answer : Cross over distortion in class - B push-p amplifiers:  1. Is due to transistor operating near saturation region  2. Can be eliminated by operating them in class operation  3. Occurs because two power transistors do not exactly matching parameters  4. Always occurs in low signal area

Compare the SI and CI engine on the basis of: (i) Compression Ratio (ii) Operating Speed (iii) Power O/P per weight.

Description : Compare the SI and CI engine on the basis of: (i) Compression Ratio (ii) Operating Speed (iii) Power O/P per weight.

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Description : Compare PAM, PWM, and PPM on the basis of i. Variable characteristics ii. Bandwidth iii. Information contained in iv. Transmitted power

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State classification of Amplifiers.

Description : State classification of Amplifiers.

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Comment on the effect of negative feedback on the gain, input and output resistance of the feedback amplifiers.Describe the gain bandwidth product term used in this context and its importance.

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Define the term related to power amplifier. (i) Efficiency (ii) Voltage gain

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Define each of following terms of operational amplifiers i) Slew rate ii) Input offset voltage iii) Voltage gain iv) Input capacitance

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Description : Why are frequency modulation transmitters more efficient? A. Because their power is increased by class C amplifiers B. Because their power is increased by class A amplifiers C. Because their power is increased by class B amplifiers D. Because their power is increased by class AB amplifiers

Last Answer : A. Because their power is increased by class C amplifiers

Explain the term crossover distortion. State methods to overcome it.

Description : Explain the term crossover distortion. State methods to overcome it.

Last Answer : Explanation:-  * Cross over distortion occurs in Class B push pull Amplifier.  * In the push-pull configuration, the two identical transistors get into conduction, one after the other and the output ... transistors won t be OFF at the same time. The remedy is to use Class AB amplifier.

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Which of the following contributes to harmonics distortion in amplifiers? A) Positive feedback B) Presence of noise C) Defective active device D) Non linearity in active device.

Description : Which of the following contributes to harmonics distortion in amplifiers? A) Positive feedback B) Presence of noise C) Defective active device D) Non linearity in active device.

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Description : When the conduction current density and displacement current density are same, the dissipation factor will be a) Zero b) Minimum c) Maximum d) Unity

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Description : Compare small signal amplifier with power amplifier

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Description : Which of the following statements regarding evacuated tube collectors (ETC) are true? i) ETC is used for high temperatures upto 150oC ii) because of use of vacuum between two concentric glass tube, higher amount of heat is ... upon the ambient temperature i & iii b) ii & iii c) i & iv d) i & ii

Last Answer : d) i & ii

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Since the characteristics of the device shown in figure 'A' of the illustration includes a stable voltage and low current while operating, it can be suitably used in _____________. EL-0065 A. oscillators and SCR trigger circuits B. class A and B amplifiers C. generator rectifier and filtering supplies D. all of the above

Description : Since the characteristics of the device shown in figure 'A' of the illustration includes a stable voltage and low current while operating, it can be suitably used in _____________. EL-0065 A. oscillators ... . class A and B amplifiers C. generator rectifier and filtering supplies D. all of the above

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Description : Draw Bootstrap sweep generator circuit. Compare Miller Integrator and bootstrap sweep generator with respect to the technique used.

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Compare the fixed voltage regulators using 78XX and 79XX.

Description : Compare the fixed voltage regulators using 78XX and 79XX.

Last Answer : Compare the fixed voltage regulators using 78XX and 79XX.

Compare between RC phase shift oscillator and crystal oscillator.

Description : Compare between RC phase shift oscillator and crystal oscillator.

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Description : In ΔABC and ΔDEF, AB = DE, AB || DE, BC = EF and BC || EF. Vertices A, B and C are joined to vertices D, E and F respectively (see Fig. 8.22). Show that (i) quadrilateral ABED is a parallelogram ( ... CF and AD = CF (iv) quadrilateral ACFD is a parallelogram (v) AC = DF (vi) ΔABC ≅ ΔDEF. -Maths 9th

Last Answer : . Solution: (i) AB = DE and AB || DE (Given) Two opposite sides of a quadrilateral are equal and parallel to each other. Thus, quadrilateral ABED is a parallelogram (ii) Again BC = EF and BC || EF ... (Given) BC = EF (Given) AC = DF (Opposite sides of a parallelogram) , ΔABC ≅ ΔDEF [SSS congruency]

Describe the operation of class-C type of power amplifier with the help of neat sketch.

Description : Describe the operation of class-C type of power amplifier with the help of neat sketch.

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Which of the following statements are true? i) reactive current is necessary to build up the flux for the magnetic field of inductive devices ii) some portion of reactive current is converted into work iii) the cosine of angle between kVA and kVAr vector is called power factor iv) the cosine of angle between kW and kVA vector is called power factor a) i & iv b) ii & iii c) i & iii d) iii & iv

Description : Which of the following statements are true? i) reactive current is necessary to build up the flux for the magnetic field of inductive devices ii) some portion of reactive current is converted into work iii) the cosine of angle ... called power factor a) i & iv b) ii & iii c) i & iii d) iii & iv

Last Answer : a) i & iv

What is the advantage of sidetone? A. High transmission efficiency B. Results to a strengthened signal C. No energy dissipation D. Assures that the telephone is working

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Last Answer : D. Assures that the telephone is working

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Description : Compare third party insurance and comprehensive on following parameters: i. Risk cover ii. Premium iii. Application of vehicle iv. Condition

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Compare orifice plate with venturi tube with reference to: (i) Working principle (ii) Construction (iii) Cost (iv) Pressure loss

Description : Compare orifice plate with venturi tube with reference to: (i) Working principle (ii) Construction (iii) Cost (iv) Pressure loss

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Compare sky wave and space wave propagation w.r.t. following points. (i) Frequency range (ii) Effect of fading (iii)Polarization (iv)Application

Description : Compare sky wave and space wave propagation w.r.t. following points. (i) Frequency range (ii) Effect of fading (iii)Polarization (iv)Application

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Compare indoor and outdoor sub-station on given points : (i) Capital cost (ii) Time required for completion (iii) Availability of natural light (iv) Space required

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Compare AC & DC track circuits on i) Length of circuit ii) Application iii) Effect of stray currents. iv) Maintenance

Description : Compare AC & DC track circuits on i) Length of circuit ii) Application iii) Effect of stray currents. iv) Maintenance

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In class - A power amplifier, the collector dissipation is maximum when

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Last Answer : In class - A power amplifier, the collector dissipation is maximum when no signal is present

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Description : Which of the following are the benefits of E-marketing? i) Speed ii) Reach and Penetration iii) Ease and Efficiency iv) Low Cost v) Targeted audience A) i, ii, iii and iv only B) ii, iii, iv and v only C) i, iii, iv and v only D) All i, ii, iii, iv and v

Last Answer : D) All i, ii, iii, iv and v

Differentiate induced draft and forced draft cooling towers based on (i) Location of fan (ii) Corrosion of blades (iii) Efficiency (iv) Fan size

Description : Differentiate induced draft and forced draft cooling towers based on (i) Location of fan (ii) Corrosion of blades (iii) Efficiency (iv) Fan size

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