Description : Common basic applications for the operational amplifier include ____________. A. counting, pulsing and clocking amplifiers B. summing, scaling and difference amplifiers C. step-up, step-down and rectifying amplifiers D. all of the above
Last Answer : Answer: B
Description : To provide its unique characteristics to analog circuits, the operational amplifier is made up of a/an ______________. A. voltage amp, current amp and output amp B. input amp, power amp and output amp C. scaling amp, power amp and voltage amp D. differential amp, voltage amp and output amp
Last Answer : Answer: D
Description : If C4 were removed from the circuit, what would happen to the output of the amplifier?
Last Answer : The output would decrease. (C4 decouples R2 preventing degenerative feedback from R2.)
Description : What components form the input-signal-developing impedance for the amplifier?
Last Answer : C2 and the secondary of T1.
Description : What two methods are used to compensate for the problems that cause low gain in an rf amplifier?
Last Answer : . RF transformers are used and the transistor is neutralized.
Description : What problem is caused in an rf amplifier by a loosely coupled transformer?
Last Answer : A too-narrow bandpass.
Description : What is the most common form of coupling for an rf amplifier?
Last Answer : Transformer coupling.
Description : Can a parallel LC circuit be used as the frequency determining network for an rf amplifier?
Last Answer : Yes.
Description : What is the purpose of a frequency-determining network in an rf amplifier?
Last Answer : To provide maximum impedance at the desired frequency.
Description : If the output impedance of an amplifier circuit is decreased, what is the effect on the gain?
Last Answer : The gain decreases.
Description : If the input-signal-developing impedance of an amplifier is increased, what is the effect on the gain?
Last Answer : The gain increases.
Description : What component in an amplifier circuit tends to limit the low-frequency response of the amplifier?
Last Answer : The coupling capacitor (C3).
Description : What compone What components What components can be used to increase the high frequency response of an amplifier?
Last Answer : Peaking coils.
Description : What is the major factor that limits the high-frequency response of an amplifier circuits?
Last Answer : The capacitance of the circuit.
Description : What are the factors that limit the frequency response of a transistor amplifier?
Last Answer : The capacitance and inductance of the circuit and the interelectrode capacitance of the transistor.
Description : If current gain is required from an rf amplifier, what type of component should be used as an output coupling element?
Last Answer : A step-down transformer.
Description : What are the upper and lower frequency limits of an amplifier?
Last Answer : The half-power points of a frequency-response curve. The upper and lower limits of the band f frequencies for which the amplifier is most effective.
Description : What is the bandwidth of an amplifier?
Last Answer : The difference between the upper and lower frequency limits of an amplifier.
Description : When is degeneration tolerable in an amplifier?
Last Answer : When it is necessary to prevent amplitude distortion.
Description : In the basic transistor amplifier discussed earlier, what is the relationship between the polarity of the input and output signals?
Last Answer : The signals are opposite in polarity or 180 degrees out of phase with each other.
Description : What amplifier class of operation is the most inefficient but has the least distortion?
Last Answer : Class A.
Description : What two primary items determine the class of operation of an amplifier?
Last Answer : The amount of bias and the amplitude of the input signal
Description : The input and output signals of a JFET amplifier have what phase relationship?
Last Answer : They are 180 degrees out of phase.
Description : What is used to bias a magnetic amplifier so that the control winding remains free to accept control (input) signals?
Last Answer : A bias winding and associated circuitry.
Description : What is the purpose of the rectifier in a magnetic amplifier?
Last Answer : The rectifier eliminates hysteresis loss.
Description : At what portion of the magnetization curve should a magnetic amplifier be operated?
Last Answer : . The knee of the curve.
Description : What is the basic principle of a magnetic amplifier?
Last Answer : change in inductance in a series LR circuit causes a change in true power.
Description : What is the frequency classification of a magnetic amplifier
Last Answer : An audio (or low) frequency power amplifier.
Description : Can a difference amplifier have more than two inputs?
Last Answer : No
Description : What is the difference between a subtractor and a difference amplifier?
Last Answer : . The difference amplifier multiplies the difference between the two inputs by the gain of the circuit while the subtractor merely subtracts one input signal from the other
Description : Can a summing amplifier have more than two inputs?
Last Answer : Yes, a summing amplifier can have as many inputs as desired.
Description : What is the difference between a summing amplifier and an adder circuit?
Last Answer : The adder simply adds the input signals together while the summing amplifier multiplies the sum of the input signals by the gain of circuit.
Description : If the unity-gain point of the operational amplifier used in question 24 is 500 kilohertz, what is the bandwidth of the circuit?
Last Answer : 50 kilohertz (Gain = 10; Gain-Bandwidth Product = 500,000) 500,000(Hz)
Description : In the inverting configuration, what is the voltage (for all practical purposes) at the inverting input to the operational amplifier if the input signal is a 1-volt, peak-to-peak sine wave?
Last Answer : 0 volts.
Description : What does the term "closed-loop" mean in the closed-loop configuration of an operational amplifier?
Last Answer : The use of degenerative (negative) feed-back
Description : What are the three requirements for an operational amplifier?
Last Answer : . Very high gain, very high input impedance, very low output
Description : If the single-input, differential-output, differential amplifier has an output signal taken between the two output terminals, what will the peak-to-peak amplitude of this combined output be?
Last Answer : 200 millivolts. A-18. a. Differential amplifier
Description : If the differential amplifier is configured with a single input and differential outputs, what will the output signals be?
Last Answer : Each output will be a sine wave with a peak-to-peak amplitude of 100 millivolts. The output signals will be 180 degrees out of phase with each other.
Description : If the two input signals to a difference amplifier are equal in amplitude but neither in phase nor 180 degrees out of phase, what will the output signal be?
Last Answer : . A different shape than the input signals but larger in amplitude.
Description : If only one input signal is used with a difference amplifier, what will the output signal be?
Last Answer : Equal in shape and frequency to the input signal; larger in amplitude than the input signal; half as large in amplitude as when two input signals were used that were 180 degrees out of phase.
Description : If the two input signals to a difference amplifier are equal in amplitude and 180 degrees out of phase, what will the output signal be?
Last Answer : Equal in shape and frequency to each input signal and larger in amplitude by two times than
Description : . If the two input signals of a difference amplifier are in phase and equal in amplitude, what will the output signal be?
Last Answer : No output (the signals will "cancel out").
Description : What two transistor amplifier configurations are combined in the single-transistor, two-input, single-output difference amplifier?
Last Answer : Common emitter (CE) and common base (CB)
Description : How many inputs and outputs are possible with a differential amplifier?
Last Answer : Two inputs, two outputs.
Description : What the three basic components make up the typical magnetic amplifier?
Last Answer : Two saturable reactors and a transformer.
Description : What is the advantage of designing a limited bandwidth into a servo amplifier?
Last Answer : Unwanted noise-generated frequencies are rejected
Description : What happens to the overall gain of a lin-log amplifier as each stage saturates?
Last Answer : Decreases.
Description : When a large signal and a small signal are applied to a lin log amplifier at the same time, what is the effect on the small signal?
Last Answer : Amplification is reduced.
Description : The IF amplifiers are connected in what amplifier configuration?
Last Answer : Cascade.
Description : What type of klystron is used as the final stage of a power- amplifier transmitter?
Last Answer : Multicavity klystron.